P5 Cell Planning and Design Guide_V1-R2

Redline Cell Planning Guidelines

Engineering and Partner Services

Prepared for Redline Certified Partners Redline Communications Inc.

Redline Document No: P5

Subject to Change Without Notice

Redline Cell Planning Guidelines Proprietary Redline Communications © 2006 - 2 -

Copyright Information All rights reserved 2006. The information in this document is proprietary to Redline Communications Inc. This document may not in whole or in part be copied, reproduced, or reduced to any medium without prior consent, in writing, from Redline Communications Incorporated.

Contact Information Redline Communications Inc. 302 Town Center Blvd. Markham, ON Canada L3R 0E8

Web site: http://www.redlinecommunications.com Sales Inquiries: North American Toll-free International

[email protected] 1-866-633-6669 [email protected]

Support: Email Telephone

[email protected] Contact your Redline Distributor

Document File Name P5 Cell Planning and Design Guide_V1-R2.doc

Disclaimer The statements, configurations, technical data, and recommendations in this document are believed to be accurate and reliable, but are presented without express or implied warranty. Additionally, Redline makes no representations or warranties, either expressed or implied, regarding the contents of this product. Redline Communications shall not be liable for any misuse regarding this product. The information in this document is subject to change without notice.


Revision History Date Version Rev Author Note

23-Aug-06 1.0 2.0 Partner Services

Edits; Release


CONTENTS 1 INTRODUCTION .....................................................................................................................................9

1.1 DOCUMENT PURPOSE ..........................................................................................................................9 1.2 DOCUMENT SCOPE ..............................................................................................................................9 1.3 ADDITIONAL TOOLS AND RESOURCES .....................................................................................................9

2 THE REDLINE DEPLOYMENT PROCESS FLOW...................................................................................10 2.1 PROCESS DESCRIPTION......................................................................................................................10 2.2 PROCESS FLOWCHARTS .....................................................................................................................12 2.3 PRE-SALES STAGE ............................................................................................................................14 2.4 PLANNING PHASE ..............................................................................................................................14

2.4.1 Network Assessment ................................................................................................................14 2.4.2 Project Management .................................................................................................................15 2.4.3 Detailed Site Survey and Propagation Drive Tests ......................................................................15 2.4.4 IP Networking Plan ...................................................................................................................15 2.4.5 Cell Planning and Network Design .............................................................................................15 2.4.6 Wireless Site Identification.........................................................................................................15 2.4.7 Detailed Scope of Work.............................................................................................................15

3 THE CELL DESIGN PROCESS AND TECHNOLOGY .............................................................................16 3.1 PROCESS OVERVIEW .........................................................................................................................16 3.2 TECHNOLOGY BACKGROUND INFORMATION ...........................................................................................16

3.2.1 Link Budget ..............................................................................................................................16 3.2.2 Propagation Environment at 3.5 GHz .........................................................................................17 3.2.3 Fading in NLOS Environment ....................................................................................................19 3.2.4 Frequency Reuse .....................................................................................................................23 3.2.5 Adjacent Channel Rejection ......................................................................................................23 3.2.6 C/I, C/N, and CINR ...................................................................................................................24 3.2.7 AN100 Frequency Reuse Studies ..............................................................................................25 3.2.8 Antenna Concepts ....................................................................................................................30 3.2.9 Preliminary Coverage Planning Using the Link Budget Tool.........................................................33 3.2.10 Site selection considerations .....................................................................................................34 3.2.11 Capacity Planning.....................................................................................................................35

4 CELL PLANNING PROCESS STEPS.....................................................................................................47 4.1 DATA COLLECTION.............................................................................................................................49

4.1.1 Topography and Clutter Database Selection...............................................................................49 4.1.2 Network Assessment and Site Survey Data................................................................................49 4.1.3 Propagation Model Calibration. Drive test utility. .........................................................................49 4.1.4 3.5 GHz Spectrum Channel Allocations ......................................................................................50 4.1.5 Product Specification Data ........................................................................................................54

4.2 NETWORK PLANNING .........................................................................................................................55 4.2.1 Site Selection and coverage planning.........................................................................................55 4.2.2 Capacity Planning using the CelPlanner Tool .............................................................................56 4.2.3 Frequency Planning..................................................................................................................57 4.2.4 Performance Analysis ...............................................................................................................58

4.3 PLANNING UPDATE............................................................................................................................59 4.4 BACKHAUL SYSTEM DESIGN................................................................................................................59 4.5 CELL PLANNING PROCESS OUTPUT......................................................................................................61

5 CELL DEPLOYMENT ............................................................................................................................63 5.1 SINGLE CELL, MULTIPLE SECTORS .......................................................................................................63

5.1.1 Co-located Sectors: Deployment Considerations ........................................................................63


5.1.2 Four-Sector Scenario................................................................................................................64 5.1.3 Six-Sector Scenario ..................................................................................................................65 5.1.4 Single Cell Simulations..............................................................................................................67

5.2 MULTIPLE CELLS ...............................................................................................................................76 5.2.1 Multi-Cell Frequency Reuse Concepts .......................................................................................76 5.2.2 Multi-Cell Frequency Plans ........................................................................................................81 5.2.3 Cell Size Recommendations ......................................................................................................89 5.2.4 Multi-Cell Synchronization .........................................................................................................89 5.2.5 Application Examples ................................................................................................................90 5.2.6 Frequency Plan Simulations ......................................................................................................93

APPENDIX A GLOSSARY .................................................................................................................... 110 APPENDIX B ADDITIONAL FREQUENCY REUSE AND INTERFERENCE DIAGRAMS .......................... 112 APPENDIX C REFERENCES ................................................................................................................ 115


List of Tables Table 1: Adjacent channel rejection values .....................................................................................................23 Table 2: AN-100 required C/I values ..............................................................................................................24 Table 3: RedMAX (AN-100U) required C/I values............................................................................................24 Table 4: Path loss exponent ..........................................................................................................................27 Table 5: Modulation types and SNR values ....................................................................................................27 Table 6: Downtilt effects; 90º antenna, vertical BW 9º......................................................................................32 Table 7: Downtilt effects, 60º antenna, vertical BW 10º....................................................................................32 Table 8: AN100U maximum subscriber density supported ...............................................................................38 Table 9: Typical bandwidth requirements for VoIP codecs ...............................................................................39 Table 10: Number of VoIP calls per sector and supported users ......................................................................39 Table 11: Data rates as a function of modulation, coding, and channel BW, AN-100U (RedMAX) CP=1/4 ..........40 Table 12: Modulation schemes available .......................................................................................................44 Table 13: Throughput distribution simulation across the sector ........................................................................45 Table 14: Channelization plan with lower end 3403 MHz for lower sub-band.....................................................50 Table 15: Example of channelization plan with lower end 3403 MHz for lower sub-band- 7 MHz channel...........51 Table 16: Example of CEPT1403 channelization plan for lower sub-band-3.5 MHz channel...............................52 Table 17: Example of CEPT1403 channelization plan for upper sub-band-3.5 MHz channel ..............................53 Table 18: Example of CEPT1403 channelization plan for lower sub-band-7 MHz channel .................................53 Table 19: Example of CEPT1403 channelization plan for upper sub-band-7 MHz channel .................................54 Table 20: Data rates as a function of modulation, coding, and channel BW, AN-100* ........................................55 Table 21: Data rates as a function of modulation, coding, and channel BW, AN-100U (RedMAX) CP=1/4 ..........55 Table 22: C/I as function of frequency reuse distance and modulation scheme .................................................80 Table 23: Frequency spectrum required per BS configuration and frequency reuse factors used. .......................89 Table 24: Frequency Plan 1O, frequencies and antenna polarities per base station...........................................97 Table 25: Frequency Plan 2O, frequencies and antenna polarities per base station...........................................99 Table 26: Frequency Plan 3O, frequencies and antenna polarities per base station......................................... 100 Table 27: Frequency Plan 4O, frequencies and antenna polarities per base station......................................... 102 Table 28: Frequency Plan 5O, frequencies and antenna polarities per base station......................................... 104 Table 29: Frequency Plan 6O, frequencies and antenna polarities per base station......................................... 105 Table 30: Frequency Plan 7O, frequencies and antenna polarities per base station......................................... 107 Table 31: Frequency Plan 8O, frequencies and antenna polarities per base station......................................... 109


List of Figures Figure 1: Redline's network design and implementation process ......................................................................10 Figure 2: Planning Stage...............................................................................................................................12 Figure 3: Building Stage ................................................................................................................................13 Figure 4: Comparison of Suburban Path Loss Models .....................................................................................18 Figure 5: Rician Fading distributions and K Factors .........................................................................................21 Figure 6: K factors for typical conditions of 10m and 3m of antenna height .......................................................22 Figure 7: C/I: Interference between hexagonal cells in LOS, C/I vs frequency reuse distance............................27 Figure 8: Interference between hexagonal cells in LOS, fade margin reduction .................................................28 Figure 9: C/I: Interference between hexagonal cells in NLOS, C/I vs reuse distance..........................................28 Figure 10: Interference between hexagonal cells in NLOS, Fade margin reduction [dB].....................................29 Figure 11: Downtilting: lower 3dB, main beam, and upper 3 dB distances .........................................................31 Figure 12: Effect of mechanical downtilt on a 90º Kathrein antenna: .................................................................32 Figure 13: Redline Link Budget tool................................................................................................................34 Figure 14: Capacity planning flowchart ...........................................................................................................36 Figure 15: The Cell Design Process Flow .......................................................................................................48 Figure 16: CelPlan - Traffic simulation results .................................................................................................57 Figure 17: CelPlan - Automatic Frequency Planning and Optimization parameters ............................................58 Figure 18: Figure 20: CelPlan Time Outage Performance Analysis Predictions .................................................59 Figure 19: CelPlan - Backhaul Design window................................................................................................60 Figure 20: CelPlan Backhaul Design Results per link ......................................................................................60 Figure 21: Plot of region coverage indication signal level, modulation schemes and coverage ...........................61 Figure 22: Detailed Network and Site Configuration with frequency plan...........................................................62 Figure 23: Physical antenna separation specifications .....................................................................................64 Figure 24: An example of a four-sector, two-frequency cell ..............................................................................65 Figure 25: An example of a six-sector, three-frequency cell .............................................................................66 Figure 26: Reuse pattern N=3........................................................................................................................76 Figure 27: Reuse pattern N=4........................................................................................................................76 Figure 28: Reuse Pattern N=7.......................................................................................................................77 Figure 29: Frequency reuse variables ............................................................................................................77 Figure 30: Reuse patterns and distance factors ..............................................................................................78 Figure 31: Distances from the center cell as a function of the cell radius R0......................................................78 Figure 32: C/I as the ratio of distances ...........................................................................................................79 Figure 33: Frequency reuse of co-located modulation schemes .......................................................................81 Figure 34: Frequency Plan 1: N=4, 60º Sectors, NLOS/LOS-OLOS Rx Conditions ............................................83 Figure 35: Frequency Plan 2: N=4, 90º Sectors, NLOS/LOS-OLOS Rx Conditions ............................................84 Figure 36: Frequency Plan 4: N=3, 60º Sectors, NLOS/LOS-OLOS Rx Conditions ............................................85 Figure 37: Frequency Plan 4: N=3, 90º Sectors, NLOS/LOS-OLOS Rx Conditions ...........................................86 Figure 38: Frequency Plan 5: N=2, 90º Sectors, NLOS Rx Conditions, 4 Frequencies. ......................................87 Figure 39: Frequency Plan 7: N=2, 60º Sectors, NLOS Rx Conditions, 6 Frequencies .......................................88 Figure 40: Example 1, 7MHz plan in two sites.................................................................................................90 Figure 41: Example 2, Frequency plan N=4 and D=3.46R ...............................................................................92 Figure 42: Redline Link Simulator Parameters ................................................................................................93 Figure 43: Redline Link Receiver Simulation Parameters .................................................................................94 Figure 44: Link Simulator Receiver Parameters ..............................................................................................95 Figure 45: Frequency Plan 1O, Scenario........................................................................................................96 Figure 46: Frequency Plan 1O, percentage of area per modulation rate ...........................................................97 Figure 47: Frequency Plan 2O, Scenario........................................................................................................98 Figure 48: Frequency Plan 2O, percentage of area per modulation rate ...........................................................98 Figure 49: Frequency Plan 3O, Scenario........................................................................................................99 Figure 50: Frequency Plan 3O, percentage of area per modulation rate ......................................................... 100 Figure 51: Frequency Plan 4O, Scenario...................................................................................................... 101 Figure 52: Frequency Plan 4O, percentage of area per modulation rate ......................................................... 101 Figure 53: Frequency Plan 5O, Scenario...................................................................................................... 103 Figure 54: Frequency Plan 5O, percentage of area per modulation rate ......................................................... 104


Figure 55: Frequency Plan 6O, Scenario...................................................................................................... 105 Figure 56: Frequency Plan 6O, percentage of area per modulation rate ......................................................... 105 Figure 57: Frequency Plan 7O, Scenario...................................................................................................... 106 Figure 58: Frequency Plan 7O, percentage of area per modulation rate ......................................................... 106 Figure 59: Frequency Plan 8O, Scenario...................................................................................................... 108 Figure 60: Frequency Plan 8O, percentage of area per modulation rate ......................................................... 108

Redline Cell Planning Guidelines Proprietary Redline Communications © 2006 9

1 Introduction Wireless network planning is a complex, iterative process involving multiple disciplines, and requires that a planner take into account and work with a multitude of technological, geographical, business, and network data. Cell planning is an integral part of any network design, especially for WiMAX networks where there are hundreds to thousands of CPEs. When it is time to implement a wireless network, an RF network design is mandatory for determining the number of base stations and their locations, achieving the required coverage and system capacity, and making optimum use of the frequency spectrum.

1.1 Document Purpose This document captures Redline’s cell planning guidelines for Partners and customers in the process of product application and system design. Given the breadth of the subject matter and the variety of concepts and technologies involved in this exercise, the goals this document aims to achieve are: § To introduce the fundamentals required in the WiMAX network design using Redline products. § To offer reference material to help the user to become familiar with the process and implications of cell

planning. § To communicate cell planning knowledge required for the preliminary stages of the design exercise.

1.2 Document Scope The information in this document pertains to systems and networks that make use of Redline’s AN-100 and AN100U (RedMAX) products, Base Station and outdoor CPE.

1.3 Additional Tools and Resources Users may start using the concepts presented in this document for the initial stages of network planning. However, for the final network design exercise, it is strongly recommended to use automated RF planning tools with WiMAX capabilities, such as the CelPlanner suite, from CelPlan Technologies, used by Redline. When opting for the purchase of a particular RF planning tool with WiMAX-specific capabilities, customers should consider getting training for the operation of the tool. Alternatively, to perform required RF studies using specific environmental data, customers may want to consider contracting external parties specializing in RF, such as consulting firms or system integrators. For further studies and background information, users may wish to consult the several references at the end of this document, in Appendix C.


2 The Redline Deployment Process Flow This section provides an overview of the entire business process and introduces the Planning and Building, focusing on Cell Planning and Network Design stages. The figure below shows Redline’s business process for managing the flow of activities, tasks and responsibilities involved in the design and implementation of networks using the AN-100/AN-100U products.

Training & Certification

Network Migration Spares Management Training Scope of Work

Network Upgrades On-Site Maintenance Customer Acceptance Site Identification

Re-certification Training

On-Site Support Access Cell Deployment

Cell Planning & Network Design

Network Acceptance On-Line Support NOC Deployment Network Planning

Maintaining the Network

Technical Support Backhaul Equipment Deployment

Detailed Site Surveys

Network Performance & Optimization

Extended Warranty Site Acquisition Network Assessment

Network Assessment Service Level Agreements

Project Management (Executing)

Project Management (Planning)

Sustaining Operating Building Planning

Figure 1: Redline's network design and implementation process

2.1 Process description

As shown in the Figure 1 above, Redline’s business process for managing the flow of activities, tasks and responsibilities involved in the design and implementation of networks using the AN-100/AN-100U products consists of four stages: Planning, Building, Operating and Sustaining (detailed information on Redline’s overall business process can be found in the document “Redline Deployment Process Flow”, available at Redline’s Partner Site at the Deployment Process and Guidelines area. See Ref 7 in Appendix C). As shown in Figure 2, Cell Planning and Network Design is only one of the stages of the process. In order to start any cell planning exercise, events of previous stages need to take place in a sequential manner. Similarly, a cell planning exercise is followed by other stages that should be considered by the customer in order to have complete control of the project objectives. After the Planning Phase is completed, the design should be locked down and the customer should send the P.O. based on the statement of work. Most importantly, the sites should be identified and the certified partner should receive a notice to proceed with installation. The Building Phase is the next phase after the Planning Phase and


includes seven main stages. The following flowcharts show all the steps of Redline’s Planning and Building stages along with typical deliverables. The other major stages of Redline’s Business Process, Operating and Sustaining, are covered in separate documents available at the Redline’s Partner Site.


2.2 Process Flowcharts

Prospect QualifiedSales Proposal, RFPs Completed, Service PO received by partner,Deployment type Identified (Beta Trial, Market Trial, or GA).

NetworkAssessment

Owner: Partner's Sales Person and Engineer Redline Sales Person P.1.1 Review client's business requirements P.1.2 Review client's network & backhaul concept P.1.3 Review list of candidate sitest P.1.4 Preliminary Network services and Coverage P.1.5 Identify Red Flag Issues P.1.6 Demarkation Points established

Process Deliverable: Network Assessment Report

DetailedSite Survey

Owner: Partner's Engineers Partner Services P.3.1 Communicate with support structure landlord for available antenna placement P.3.2 Antenna support structure vertical plan and compound drawing P.3.3 Equipment location, cable runs, cabinet locations. P.3.4 Coverage area Survey P.3.5 Completed site survey document

Process Deliverable: Complete Site Survey/Network Topology Report

ProjectManagement

(Planning)

Owner: Partner's Project Manager Partner Services P.2.1 Project Kick-off - charter P.2.2 Project Schedule P.2.3 Project Resources P.2.4 Project responsibility matrix with initials and dates P.2.5 Project Exclusions (ie. CPE, terminals and internet infrastructure) P.2.6 Provide Progress Reports to Team Members P.2.7 Co-ordination of Services & Equipment Quotation P.2.8 Delivery of Site lock-down and obtain customer approval for design P.2.9 Identify key performance indicator (KPI)

Process Deliverable: Project Plan

Network Planning

Owner: Partner's Sales Engineers Partner Services P.4.1 Work with client on IP Design and networking plans. P.4.2 Provide IP topology drawing including IP addressing scheme P.4.3 Deliver Network plan document P.4.4 Create a Domain Name System (DNS) map

Process Deliverable: Complete Network Plan Report

Cell Planning andNetwork Design Owner: Partner's RF Engineers Partner Services

P.5.1 Cell Planning Design Document P.5.1.1 Recommended Antenna Heights & Azimuth & Polarization P.5.1.2 Recommended Antenna Models & Antenna Sub-system Components P.5.1.3 Frequency Planning P.5.1.4 RF Propagation Prediction per site P.5.1.5 Subscriber Capacity Analysis per Sector P.5.2 Design the entire Network P.5.3 Create the Network diagram and list of Network requirements

Process Deliverable: Cell Planning Document

Phase 2

DetailedScope of Work

Owner: Customer and Partner Partner Services P.6.1 Identify the locations for the Outdoor and Indoor units P.6.2 Decision on who is responsible P.6.3 Complete notice to proceed P.6.4 Contract signed Process Deliverable: Site Identification Completed and Documented

Redline Process Guidance

P.1

P.2

P.3

P.7

P.5

P.4

Phase 1 Deliverable: Partner submits SOW to the customer

Phase 1: Planning

Owner: Partner's System Engineer Partner Services P.6.1 Identify the locations for the Outdoor and Indoor units P.6.2 Completed Statement of Work Process Deliverable: Detailed Scope of Work (SOW)

Wireless SiteIdentification

P.6

Figure 2: Planning Stage


Owner: Partner's Project Manager Partner Services B.1.1 Sub-Contractor Coordination B.1.2 Site Coordination B.1.3 Equipment Staging & Procurement B.1.4 Project Communication - progress reports, change order management B.1.5 Cost Tracking B.1.6 Installation/Configuration/Commissioning checklists B.1.7 Test plan accepted by customer (ATP) Process Deliverable: Implementation Plan

From Phase 1

Design is Locked DownCustomer has sent PO based on SOWSites are identified, received notice to proceed

ProjectManagement(Execution)

NetworkOperations Center

(NOC)Deployment

Owner: Partner's Post-Sales Engineer Partner Services B.5.1 Installation assessment completed B.5.2 Configuration assessment completed B.5.3 Commissioning assessment completed B.5.4 Testing B.5.5 Optimization of Base Station Sites to meet Coverage Area B.5.6 Commissioning assessment completed

Process Deliverable: Cell Commissioning and As-built Drawings Completed

Access CellDeployment

Owner: Partner's Post-Sales Engineer Partner Services B.4.1 Decision on who is responsible B.4.2 Installation B.4.3 Configuration B.4.4 Testing

Process Deliverable: NOC Commissioning and Site Acceptance forms

Training

Owner: Partner's RCE Person Partner Services: Technical Training B.7.1 On-Site Training B.7.1.1 Training based on Customer requirements B.7.2 Redline Certified Expert Training (RCE)

Process deliverable: On site, Partner site or Redline based trainingTo Phase 3

CustomerAcceptance

Redline Process Guidance

WirelessSite Acquisition

Owner: Customer and Partner Partner Services B.2.1 Decision on Who is Responsible - tasks & when B.2.1.1 Complete and Submit Application to Landlord B.2.1.2 Provide applicable fees for site access, structural analysis, walk-thru B.2.1.3 Provide building permit B.2.1.4 Provide construction drawings B.2.1.5 Provide requested certification and insurance B.2.1.6 Provide construction schedule B.2.2 Complete Post-construction Checklist B.2.3 Contract signed

Process Deliverable: Site Acquisition Report

Phase 2 Deliverable: Network completed, commissioning and customeracceptance signed-off, Network in service.

BackhaulEquipment

Deployment

Owner: Partner's Post-Sales Engineer Partner Services B.3.1 Decision on who is responsible B.3.2 Backhaul Equipment Installation/Configuration/Testing/Commissioning B.3.3 Installation/Testing of radio equipment B.3.4 Demark point established

Process Deliverable: Backhaul Commissioning & Site Acceptance forms

B.1

B.7

B.6

B.5

B.4

B.3

B.2

Phase 2: Building

Owner: Partner's Post-Sales Engineer Partner Services B.6.1 SU-O Quick Test Plan B.6.2 Base Station Installation ATP B.6.3 Commissioning ATP B6.3.1 RedMAX Functional ATP B6.3.2 RMS Acceptance Test Plan

Process Deliverable: Customer Acceptance

Figure 3: Building Stage


2.3 Pre-Sales Stage The initial contact with a Redline Partner is typically developed through pre-sales contacts and RFPs. At this stage the customer presents their project requirements, such as areas to be covered by the wireless system, potential number of subscribers and intended data or voice services to be managed by the system, as well as specific technical questions about the product.

2.4 Planning Phase The first phase in Redline’s Deployment Process Flow is the Planning Phase. It consists of seven steps. For each step, Redline has prepared a detailed recommended guideline document. These steps consist of professional services that are typically conducted by a Redline Certified Partner and billed to their Customer.

P1. Network Assessment P2. Project Management (Planning) P3. Detailed Site Survey P4. IP Networking Plan P5. Cell Planning and Network Design P6. Wireless Site Identification P7. Detailed Scope of Work

Each step is described briefly in the following paragraphs.

2.4.1 Network Assessment This stage is key for the success of the entire planning stage and covers all the project definitions and data collection that will impact the system design. Once the customer’s preliminary questions about the technology are satisfied and a decision is made on starting a formal project with Redline, the first step in the Planning phase is a Network Assessment. During this stage the customer meets with a Redline Partner Account Manager or Sales Engineer to establish clear objectives for the project. This stage identifies the following variables. § Geographical data: maps, demographics, target areas, market penetration § Subscriber services: data, voice or other services § Deployment type: demand-driven or supply-driven § Candidate Sites list § RF Network Concept § Backhaul system concept, frequency bands, available resources § Available bandwidth (3.5 GHz) § Local regulations (for 3.5 GHz) § Project CAPEX § Project responsibility matrix § Potential technical issues § Site and cell planning lockdown criteria § Demarcation points of services in multi-vendor projects § Availability of topographic and clutter data bases for the project § Project Risk assessment

This information will be part of a Network Assessment Report to be delivered to the customer. Detailed information on the Network Assessment process can be found in the document “Network Assessment Guide” available at Redline’s Partner Site at the Deployment Process and Guidelines area. See Ref 8 in Appendix C.


2.4.2 Project Management A Redline Certified Partner’s Project Manager will kick off the project by defining the schedule, resources, responsibilities and the exclusions within this stage.

2.4.3 Detailed Site Survey and Propagation Drive Tests Once a Candidate Sites list is available, a Professional Wireless Installer and one Partner’s Field Engineer should perform a detailed survey of the sites in the candidate list. The objectives of this exercise are:

§ Determination of antenna and equipment location options per candidate site. § Verification of viability of the site to cover the target area. § Determination of potential RF interaction with other co-located services per site. § To make a propagation characterization (at 3.5 GHz) of the coverage areas. This process requires drive

tests within the intended area of the project using an existing AN100 / AN100U Sector Controller or a temporary one installed in typical points of the area type to be covered. The Partner should perform the data collection with specific tools and procedures that Redline indicates for this purpose.

Upon completion of the Site Survey stage, a Site Survey Report is generated by the Partner.

2.4.4 IP Networking Plan Once the Candidate Sites list is confirmed, a preliminary IP network design can start. The formal IP Network design will be finished once the Cell Planning and Backhaul system design are completed. A deliverable of this stage is a Preliminary IP Network Design Report.

2.4.5 Cell Planning and Network Design The Cell Planning and Network Design exercise requires a Network Assessment Report, a Site Survey Report and a Preliminary IP Network Design report. This stage covers the design of the PMP and PTP systems. It is typically carried out using automated RF planning tools capable of conducting BFWA traffic and coverage analysis. An RF planning tool will require Databases of Topography and Clutter of the coverage area. A typical deliverable of this stage is a Cell Planning and Backhaul System Design document that contains the following information: sites selected, required coverage areas, antenna parameters (type, height, azimuth, downtilt), traffic (based on simulation), frequency plan, and bandwidth required per site.

2.4.6 Wireless Site Identification This stage uses all the information gathered in the previous steps and verifies the wireless site information gathered during the site survey. This checklist will identify the locations for the base stations and CPEs (Customer Premises Equipment), including outdoor and indoor units, and determines the validity of the scope of work. Base station locations might include any number and type of locations including building rooftops and towers.

2.4.7 Detailed Scope of Work After the Cell Planning, Backhaul design and IP Planning is complete, the Redline Partner or customer can proceed to produce a detailed Scope of Work (SOW) of the project normally defined with the participation of the Professional Installer who completed the Site Survey stage. This document will be sent to the professional installers and field engineers to follow to install and commission a successful Wireless Network. Detailed information on the implementation process can be found in the document “RedMAX System Implementation Guide” available at Redline’s Partner Site in the Deployment Process and Guidelines area. See Ref 9 in Appendix C.


3 The Cell Design Process and Technology

3.1 Process Overview The cell design process starts with the consolidation of all the deliverables coming from previous stages in the business process. This stage is typically conducted through specialized services from RF consulting firms or RF system planning engineers to be hired by the Redline Partner managing the project. The objective of this stage is to satisfy, as technically possible, the coverage and service objectives expected by the customer using mainly the provided Candidate Sites list, CAPEX budget, and available 3.5 GHz bandwidth. Several iterations of this exercise may be required in order to meet the objectives of the project while following the Site and Design lockdown criteria and other agreements established during the Network Assessment. The cell design exercise requires the use of automated RF planning tools specifically suited for BFWA and WiMAX systems and having coverage analysis, traffic simulation, automatic frequency planning, and performance evaluation capabilities.

3.2 Technology Background Information This section introduces key concepts of BFWA networking applied to Redline’s AN-100/RedMAX systems. An understanding of these concepts is essential to efficient network and cell planning. Concepts that are covered include Link Budget, propagation, fading, delay spread, C/I, frequency reuse, and antennas. Furthermore, this section contains a thorough study of frequency reuse simulation based on Redline’s AN-100 product and is applicable to AN100U (RedMAX) systems.

3.2.1 Link Budget A link budget is the accounting of all of the gains and losses from the transmitter, through the medium (3.5 GHz channel) to the receiver. The following figure describes the variables involved in the general transmission model and Link Budget to be considered for the propagation between the SC and the SS.

PT = Sector Controller Power GT = Sector Controller Antenna system Gain (Antenna Gain – cable losses) GR = Subscriber Antenna system Gain (Antenna Gain – cable losses) FOR LINE-OF-SIGHT (LOS) TRANSMISSION LP, dB= Lfree-space + X , where X: random fading FREE-SPACE path loss: Lfree-space= (4pd/?)2, Lfree-space=(4pd/?)2 = (4pd)2 / (300x10-3 / f) for d in Km and f in MHz Lfree-space= A + 10nf log10(fMHz) + 10ndlog10(dkm) dB


where A = 32.44, nf=2, nd= 2 FOR NON LINE-OF-SIGHT (NLOS) TRANSMISSION LP, dB= LNLOS + Y , where Y: random fading

The factor LNLOS comes from the different propagation models available for 3.5 GHz (see section 3.2.2 below); the factor Y is the fading due mainly to multipath conditions in NLOS (Raleigh fading) or NLOS combined with LOS conditions (Rician fading). A preliminary link budget calculation can be performed using the Redline Link Budget Tool (see section 3.2.9).

3.2.2 Propagation Environment at 3.5 GHz Propagation is the transmission (spreading) of electromagnetic waves. A propagation channel is the physical medium electromagnetic wave propagation between the transmitting and receiving antennas, and includes all the factors that influence the propagation between the two antennas. Propagation of radio waves used for PMP in 3.5 GHz travels mostly under NLOS conditions and multipath effects. In order to model and predict the behavior of the radio waves traveling in this frequency band and conditions, customers can opt to use empirical channel models or physical propagation models.

3.2.2.1 Empirical Path Loss Models Several channel models, specifically for Fixed Wireless Broadband and WiMAX applications have been proposed based on different research and fieldwork. To model the characteristics of the radio propagation in this frequency band and NLOS application, models such as SUI (Stanford University Interim)-Erceg, Costi 231-WI, Costi 231-Hata, ECC33 and others have been proposed through the IEEE 802.16 Broadband Wireless Access Working Group and other organizations in Europe. The nature of such models is mostly empiric, which means that they are based on thousands of field measurements under specific conditions and generalized as a reference path loss model, with statistical variables. In some cases the models closely predict the average signal strength received at some point in a typical area similar to the one used for the research work (typically urban, suburban and rural). However, because most of these models have not been fully tested at 3.5 GHz, they do not always offer the expected results when applied to other scenarios with a variety of terrain and clutter conditions. For this reason, the results of each of these models differ and their applicability may vary substantially from one model to another. In-depth information on the channel models described, including fading considerations, can be found in Ref 2 and Ref 3 of Appendix C.


Figure 4: Comparison of Suburban Path Loss Models

Figure 4 above (source: Appendix C, Ref 6) is a comparison of a number of published path loss models for suburban morphology with an empirical model based on drive tests in the Dallas-Fort Worth area. The best agreement is found with the Cost 231 Walfisch-Ikegami model, with the following parameter settings:

Building spacing: 50 meters Street orientation: 90 degrees Average rooftop height: 8 meters Mobile antenna height: 2 meters Base antenna height: 30 meters (for the particular comparison above)

It has also been found that the Cost 231 W-I model agrees well with measured results for urban areas, provided the appropriate building spacing and rooftop heights are used. It can therefore be used for both suburban and urban areas and can allow for variations of these general categories between and within different countries. The Cost 231 Walfisch-Ikegami model is a “flat terrain” model, and it is therefore recommended that it be used in conjunction with terrain diffraction modeling for hilly areas. It was found that the weighting term for knife-edge diffraction should be set to 0.5 to minimize the lognormal standard deviation of the path loss. For this purpose, CelPlan Technologies, the creator of the RF tool used by Redline for WiMAX, developed a model known as model II Korowajczuk based on the Walfish-Ikegami model.

Note: For general reference and rough estimates of average received signal levels under specific AN100U transmission and reception conditions, and under different non-line-of-sight conditions, the model known as Erceg has been implemented within the Redline’s Link Budget Calculator version 1.09.

3.2.2.1.1 Erceg model description Below are the main characteristics of the channel model known as Erceg: § Empirical path loss model based on experimental data collected across the United States in 95 existing

macrocells.


§ Developed for three types of suburban terrain: Heavy tree condition-hilly terrain (Type A), Medium tree density-hilly to flat terrain (Type B), and Light tree density flat terrain (Type C).

§ Model derived at 1.9 GHz, corrected for 3.5 GHz. § Base station height between 10-80m. § Receiver Height between 2 to 10 m. § Cell Size from 0.1 to 8 Km. § BS antenna height should be considered as height above average terrain.

o It applies uniform conditions across the area (A, B, C conditions). o It does not identify LOS or OLOS customers who may have higher signal levels.

In terms of accuracy, in general, the empirical path loss models can offer signal prediction typically within 10 dB of standard deviation.

3.2.2.2 Physical Propagation Models These models consider the effects of specific path, terrain and clutter conditions in the propagation channel in use. In some cases they may be pure deterministic models, which demand very accurate databases, in other cases they may be physical models incorporating statistical concepts in the prediction of the signals and multipath fading. This is the case for the propagation models used by several RF planning tools in the market. These models use the actual topography and clutter information of the area and perform path loss analysis based on diffraction and reflection of the electromagnetic waves, per point of calculation and typical clutter types, using physical parameters of the environment and adding a high level of accuracy to the predicted values. For this purpose, CelPlan Technologies, the creator of the RF tool used by Redline for WiMAX, has developed a model known as model II Korowajczuk . Based on Walfish-Ikegami model and being used for 3.5 GHz, this model not only considers actual topography and clutter information but also the traveling of the waves through multiple morphologies. Ref 4 in Appendix C is a publication from CelPlan Technologies that offers in-depth information on different propagation models, including model II Korowajczuk, and environment modeling developed and used by CelPlan tools. As a rule of thumb, the accuracy of these models is a direct function of the topography and clutter database resolution used in conjunction with the RF planning tool to model the physical area and depends on the calibration or tuning of the model for the particular environment (see section 2.4.3, Detailed Site Survey and Propagation Drive Tests) In terms of accuracy, depending on the clutter database resolutions used, the physical propagation models can predict signals up to 5 dB of standard deviation.

3.2.3 Fading in NLOS Environment Fading refers to the variability or variability of the received signals around the average levels. Under NLOS conditions the fading is mostly due to multipath effects generated in the environment surrounding the propagation path, and it is significantly different from the fading shown by PTP links, which are typically in LOS, in traditional microwave. For Fixed Wireless PMP systems the degree of multipath depends on the conditions of the NLOS environment, mostly the scattering and reflection properties of the medium, the shadowing effects of buildings, trees, moving objects, ground reflections and atmospheric effects. According to different contributions made to the IEEE 802.16 Broadband Wireless Access Group, cited in Ref 2 of Appendix C, the narrow band fading in this band can be modeled through Rician and Raleigh Fading distributions. For typical conditions of NLOS environment, where the reception point has a combination of NLOS and LOS components, the Rician distributions can be applied.


Under a Rician distribution the depth of the multipath fading is a direct function of the conditions of the NLOS environment (foliage density), the distance of the receiver to the base station, the receiver antenna beamwidth, and it is an inverse function of the Rx antenna height. The fading analysis in this band is conducted through constant factors known as K factors, from which a determined fade depth can be calculated for a given probability of occurrence or reliability factor. The K factors can be calculated as follows:

( ) ( ) ( ) ( ) dBinudkFFFK bhs ++++= γ0log10log10log10log10

where:

Fs is a seasonal factor, Fs =1.0 in summer (leaves); 2.5 in winter (no leaves)

Fh is the receive antenna height factor, Fh= (h/3)0.46

; (h is the receive antenna height in meters)

Fb is the beamwidth factor, Fb = (b/17)-0.62

; (b in degrees)

ko and ? are regression coefficients, Ko = 10; ? = -0.5

d is the distance from the cell site to the SS (d in Km)

u is a lognormal variable which has zero dB mean and a std. deviation of 8.0 dB.

Once the K factors have been established, the required Fade Margin for a desired probability of occurrence of the fading can be found in the curves shown in Figure 5 below (source: Ref 2).


Figure 5: Rician Fading distributions and K Factors


Figure 6 below shows K factors for typical conditions at receiver antenna heights of 10 m and 3 m and using two antennas of different beamwidth, 15º and 8º. This figure offers a good range of selection of K factors for typical distances to the receiver point that can then be applied in the Figure 4 to find the required amplitude in db, which is the Fade Margin for a desired probability of fade depth being exceeded.

Figure 6: K factors for typical conditions of 10m and 3m of antenna height

It is important to consider that in OFDM technology the transmission bandwidth is divided into lower bit carriers with a guard interval (CP, Cyclic Prefix) at the beginning of each OFDM symbol. As a result, the ISI (inter-symbol interference), typical in single-carrier systems, is significantly reduced, making the signal more robust and resistant to multipath fading. Other features of Redline’s current AN100 and AN100U products that further alleviate the fade margin requirements include Dynamic Adaptive Modulation, Advanced Coding (FEC) and ARQ.

Note: Because the calculation of K factors, fundamental in determining the fading margins, involves complex mathematical algorithms, Redline recommends using RF propagation tools where the fading factors take into account the particular conditions of clutter and terrain topography (NLOS conditions) of the design area.

3.2.3.1 Delay Spread Delay Spread is an important notion in the propagation of signals under NLOS. It refers to the reflection characteristics of an electromagnetic wave in one particular NLOS environment. Some environments may have higher reflection attributes than others. As mentioned earlier, the main characteristic of the propagation in this frequency band is the reception through multipath conditions, which means there is always more than one signal from the same SC (transmitter) to arrive at the SS (receiver) within some time interval. The Delay Spread is associated to the RMS value of the time spread between the arrival of the first and last multipath signal at the receiver point. In OFDM and digital communications in general, the effect of the Delay Spread on a receiver can cause Inter-Symbol interference (ISI), when its value is larger than the level of tolerance of the particular receiver. In this type of interference condition the receiver cannot demodulate the original OFDM symbol, and this causes errors in the digital transmission.


As mentioned, the Delay Spread is very specific to each environment as the type of trees, buildings, construction materials and the proximity of objects may be totally different in each case; however, typical values can be found in the range of 5-10 µs for urban, 0.5 µs for suburban, and 0.2 µs for rural environments. Although the Delay Spread is characteristic of each path condition, the selection and orientation of the receiver antenna may help to control the number of different received multipath signals and hence the delay spread of the multiple signals detected at the receiver input. AN100 and AN100U RedMAX systems can be set up for specific Delay Spread scenarios by configuring the Cyclic Prefix (CP) of the OFDM symbol to a value higher than the expected channel Delay Spread. Supported values of CP length are: ¼, 1/8, 1/16, and 1/32 of the FFT span. CP is used at ¼ values for most robustness against multipath, while 1/32 is the least robust prefix mostly used in negligible multipath environments.

3.2.4 Frequency Reuse Frequency reuse refers to the ability to use the same frequencies repeatedly across a cellular system with little or no interference. This is of great importance in BFWA systems, especially in licensed bands where the number of available frequencies may be limited. Section 5.2.1 contains in-depth information on multi-cell frequency reuse concepts.

3.2.5 Adjacent Channel Rejection Adjacent Channel Rejection (ACR) is defined by the difference, in dB, between the power level of an interfering RF signal measured in the adjacent channel frequency and the power level of a desired signal, where the interfering signal causes a degradation of 3 dB in the sensitivity of the receiver. According to IEEE 802.16-2004 and WiMAX standards, the adjacent channel rejection and alternate channel rejection are measured by setting the desired signal’s strength 3 dB above the receiver sensitivity threshold under test and raising the power level of the interfering signal until the specified error rate (BER 10-6) is obtained. The power difference between the interfering signal and the desired channel is the corresponding adjacent channel rejection. In synchronized TDD or FDD systems the use of the same source of timing prevents any potential TX/RX interactions at the same base station because, in theory, all SC transmitters using the same timing source are in transmit mode, whereas all SC receivers are disabled or off during the same period of time. For any Cell Planning effort, a comprehensive adjacent channel rejection analysis should be conducted for the entire network, for both downstream and upstream links, for the same or adjacent cells. This is done using RF design tools, such as the CelPlanner Suite. For antenna co-location or interference analysis, the following ACR values can be used.

64QAM 16QAM

1st Adjacent-Channel int. (dBc) +8 +14

2nd Adjacent-Channel int. (dBc) +30 +37

1st Adjacent-Channel int. (dBc) +8 +14

2nd Adjacent-Channel int. (dBc) +30 +37

Channel Width (MHz) Adjacent Channel

Modulation

7 MHz

3.5 MHz Table 1: Adjacent channel rejection values


3.2.6 C/I, C/N, and CINR The following is a list of important terms commonly involved in interference analysis: C/I, the Carrier-to-Interference ratio, refers to the absolute ratio of the carrier signal (desired signal) to the one interference signal (undesired signal) under analysis, measured at one specific point of a propagation environment, typically at the receiver input, used to determine the minimum co-channel to interference ratio required for keeping a particular receiver within a specified BER condition. C/N, Carrier-to-Noise , is the ratio of the carrier signal to the receiver noise floor within the operating bandwidth (thermal noise) with no presence of interference. CINR, Carrier-to-Interference-plus-Noise , is the C/I ratio referred to the particular AN100 or AN100U receiver noise floor measured at the receiver output. This value provides information on the actual operating condition of the receiver, including any external interference, noise levels, and signal strength. For the effects of Cell Planning the following C/I values can be used for AN100 or RedMAX products:

Coding Rate Case 1 Case 2 CINR Thresholds LB Table 1/2 19 9.4 --- 10 QPSK 3/4 21 11.2 12.00 dB 12 1/2 26 16.4 15.75 dB 17 16 QAM 3/4 28 18.2 18.38 dB 19 2/3 32 22.7 22.13 dB 23 64 QAM 3/4 34 24.4 24.00 dB 25

Table 2: AN-100 required C/I values

Modulation/Coding Rate CINR threshold [dB] C/I Case 1, dB C/I Case 2, dB 64 QAM 3/4 23.25 37 24.4 64 QAM 2/3 21.75 30 22.7 16 QAM 3/4 18 28 18.2 16 QAM 1/2 15 26 16.4 QPSK 3/4 11.6 21 12.1 QPSK 1/2 6.75 19 9.4

Table 3: RedMAX (AN-100U) required C/I values

Case 1 refers to C/I ratios required when the carrier signal is close to the sensitivity threshold of the receiver at the particular modulation scheme. Case 2 refers to C/I ratios where the carrier signal is above the same thresholds (>10 dB).

3.2.6.1 Uplink Power Control An important factor in overall network connectivity is the uplink power. Redline’s AN-100 and AN-100U (RedMAX) systems allow the sector controller at the base station to automatically adjust the transmit power level for all registered subscriber stations. This is done by enabling, in the sector controller’s Wireless Interface Configuration area, the SS Tx Power Control Enable option and specifying an associated Reference RSS value in dBm. The sector controller continually monitors the registered subscriber stations and adjusts their transmission power to maintain optimum levels according to the Reference RSS. For optimal uplink performance, the Reference RSS can be set between –30 and –90dBm, the configured value being dependant on the: § Distance between the subscriber and base stations. § Line-of-sight condition of the wireless link between the sector controller and the subscriber station (e.g.,

LOS, OLOS, NLOS). § Average RSSI for all registered subscribers.


Improper configuration of the "Reference RSS" parameter may result in less-than-optimum uplink performance. There are no uniform recommendations for the uplink power control settings. However, as a preliminary and general guide, it is recommended that at the time of deployment the "Reference RSS" value be set to an initial value of -69dBm, considered to achieve a good balance between the throughput and the maximum reach for the SC. Following the deployment of all subscriber stations in the sector, the system performance can be further optimized by adjusting the "Reference RSSI" value to the average of all subscriber RSSI values, provided all the SSs are transmitting at the maximum Tx power of 20dBm. For example, suppose there are three SSs in a sector with the following uplink RSSI values showing on the sector controller: § -64dbm § -71dbm § -86dbm.

In this case, the average configured "Reference RSS" value on the SC would be set to -74dBm [(64+71+86)/3].

3.2.7 AN100 Frequency Reuse Studies This section contains the concepts, description and conclusions of an in-depth simulation study conducted by Redline Communications in order to quantify the frequency reuse requirements originally formulated for the AN100 system. This study was conducted with intercell interference analysis using path loss data based on the following channel models: § LOS, NLOS § Hata, COST231-Hata § COST231 Walfish-Ikegami (WI) § Erceg

Because the RF specifications and C/I requirements AN-100/RedMAX systems are similar, the conclusions of this study can be considered applicable to RedMAX systems in terms of the minimum frequency reuse factors needed; however, some differences may arise in the detailed re-use curves for RedMAX vs. AN100. This is because the SU-O antenna and transmit power are different in RedMAX compared to the AN100 SS.

3.2.7.1 Definitions, Assumptions and Equipment Used The following definitions will help to understand the subsequent graphs, concepts and conclusions. Reuse Distance Factor R. The reuse distance factor R is the normalized value of the ratio between the Inter-Cell Distance D, and the Cell Radius Ro:

R= D/Ro Thus, R=2 means two Cell Radius, this is R=2Ro or next Cell, R=4 means R=4Ro or third cell, and so on. The Reuse Distance, D is the minimum distance between two cells that can use the same frequency and is a figure of merit: a shorter frequency reuse distance implies a better spectral efficiency by frequency reuse. Fade Margin Reduction (dB). This term refers to the loss of fade margin due to inter-cell interference at a given R. In order to maintain the required level of CINR for a target BER=10-6 in the presence of interference, the [C/I] ratio must be raised, implying a wider fade margin.


C/I: in this context C/I is referring strictly to the ratio, in dB, between the Desired Signal that a SS will expect to receive from its primary cell’s SC, and I, the total interference (or Undesired Signal), coming from neighboring cells using the same frequency (F1 in this case).

Fade Margin is the amount of power (in dB) required to support any signal decrease due to environmental factors and multipath variances in the area of analysis. The frequency reuse distance is defined as the minimum distance between two cells that can use the same frequencies and is a figure of merit: a shorter frequency reuse distance implies a better spectral efficiency by frequency reuse.

3.2.7.2 Assumptions and Propagation Concepts The following assumptions were made in the current study: 1. All receivers in the study area are under NLOS conditions with respect to the BS. 2. All the Cells are transmitting in synchronized mode. 3. The short-term fade variation in the two paths is completely correlated. 4. Co-channel interference, I, is assumed to behave as Gaussian noise. 5. Path loss considerations and channel models used:

LP(D) = A + 10nf log10(fMHz) + 10ndlog10(dkm) in dB A = constant particular of each channel model related to the antenna heights. nf = Frequency loss exponent nd = Path loss exponent In general, the frequency loss exponent nf varies depending on the channel model, frequency range and environment type. It is assumed equal to 2 for free space. Also in general terms, nd varies according to the environment type. The following are typical values for nd:


Environment Path Loss Exponent nd Environment Path Loss Exponent nd Free Space 2 Urban Cellular Radio 2.7-3.5 Shadowed urban cellular 3-5 In building with LOS 1.6-1.8 In building obstructed 4-6

Table 4: Path loss exponent

6. AN-100 parameters and equipment used: PTB=23dBm, GTB=17.5dBi (60°ANTENNA), F/B 25 dB. PTS=16dBm, GTS=24dBi (8°ANTENNA) F/B 30 dB or 18dBi (20°ANTENNA) F/B 30 dB BS antenna height: 30m AGL SS antenna height: 2m AGL

C/I @ 10-6 BER [dB] Modulation Type Ideal With 5dB implementation loss

QPSK ½ 9.4 14.5 QPSK ¾ 11.2 16.2

16 QAM ½ 16.4 21.4 16 QAM ¾ 18.2 23.2

64 QAM 2/3 22.7 27.7 64 QAM 3/4 24.4 29.4

Table 5: Modulation types and SNR values

3.2.7.3 Frequency Reuse Curves The following diagrams describe the characteristics of the AN-100 system for interference between 6-sector hexagonal cells analyzed under the previous considerations and presented for Erceg C, typical suburban environment as a reference. Other results for different RF conditions and propagation models can be found in Additional Frequency Reuse and Interference Diagrams in Appendix B. In the Fade Margin Reduction curves the modulation schemes 4QAM1/2 and 4QAM3/4 correspond to QPSK1/2 and QPSK3/4.

Figure 7: C/I: Interference between hexagonal cells in LOS, C/I vs frequency reuse distance


Figure 8: Interference between hexagonal cells in LOS, fade margin reduction

Figure 9: C/I: Interference between hexagonal cells in NLOS, C/I vs reuse distance


Figure 10: Interference between hexagonal cells in NLOS, Fade margin reduction [dB]

3.2.7.4 Conclusions Higher modulation schemes such as 64 QAM need frequency reuse factors of 6 or better for minimum interference or Fade Margin Reduction. This requirement is less stringent for lower modulation schemes such as 16 QAM or QPSK, which tend to offer the same performance with reuse factors lower than 6. For all modulation schemes, lower reuse factors will always reduce the Fade Margin resulting in the need for shorter ranges per scheme or increased BER conditions. An ideal system with no interference will require R>6 for all the modulation schemes, which can be impractical.

3.2.7.5 Practical Considerations The results of the current frequency reuse studies may be used as theoretical reference; however, network designers should note that these studies were conducted with the following underlying assumptions: § Path loss attenuation: applied uniformly in all directions from the tower site. Real-life terrain and clutter

diffraction factors may offer different attenuation factors per individual path. § Antenna height: base station: at 30m AGL, subscriber: at 2m AGL. § Antenna downtilt: none. § Receivers in OLOS or NLOS conditions: path partially (OLOS) or fully (NLOS) obstructed against the sector

controller. In practice subscribers may be in a combination of LOS, OLOS and NLOS conditions with respect to the sector controller.

The conclusions of this study point to the fact that in general lower frequency reuse factors tend to reduce the typical ranges of the modulation schemes or increase the target BER of the cell. As a rule of thumb, the higher the frequency reuse factor, the higher the performance. Also, the higher the required performance, the higher the number of frequencies required in the frequency plan and 3.5 GHz spectrum. From another perspective, deployment scenarios with receiver antennas installed on rooftops where LOS may exist against other neighbor base stations require careful selection of the frequency reuse factors. As it will be shown later in the multi-cell deployment section, a frequency reuse factor of R>4 for the lowest modulation schemes is required in order to control interference level in this type of scenarios.


During the Cell Design process, an operator may wish to experiment with different frequency reuse factors in combination with lower base station antenna heights—depending on site and general area conditions. The number of frequencies and required 3.5 GHz spectrum for the project will be only determined at the end of the design process. Although simulation analysis can offer a valid approximation to the interference scenarios, in fact, the only way to assess the real effects of any frequency reuse factor on specific real scenarios would be through the Cell Design process, using a professional software tool that operates with precise terrain topography and clutter databases. Likewise, the optimum frequency plan that will fit a specific area and best serve its specific distances, capacities and sites, will be the result of an automated process within the RF planning tool, which typically optimizes the resources of bandwidth, frequencies used, and network traffic of the system. The frequency reuse factor depends on the type of scenario considered for deployment. Under common conditions of SSs in NLOS conditions (all subscribers are outside the sector controller’s line of sight), the typical reuse factors R=6/64QAM and R=2/BPSK can be used (refer to Table 22: C/I as function of frequency reuse distance and modulation scheme). For cells expected to have a mix of NLOS or LOS subscribers (for instance, customers deploying with masts above rooftops), where the SS antenna can potentially be within LOS with two base stations operating in the same frequency, higher reuse factors such as R=3 or R=4 should be used to avoid potential interference. Finally, the use of Sector Controller antenna downtilt (depending on the antenna height and terrain conditions) may also be a key factor in achieving extra isolation between sites in the field. Practical levels of gain reduction by use of downtilt can be expected in the range of 6 dB.

3.2.8 Antenna Concepts Topics in this section introduce important concepts related to antennas used in BFWA networks.

3.2.8.1 Gain Antenna gain is the ratio of the signal, usually expressed in dB, received or transmitted by a given antenna as compared to an isotropic or dipole antenna. The gain is generally relative to a half-wave dipole (Gd) when the reference antenna is a half-wave dipole isolated in space. The following is a common relation used in antenna gain description. Gain (with reference to the isotropic radiator in dBi) = Gain (with reference to ?/2 Dipole in dBd) +2.15 dB

3.2.8.2 Pattern Typical antenna patterns are three-dimensional figures showing the relative gain, or directivity, of one antenna in different angles and coordinates, typically in a spherical coordinate system. For graphical purposes these patterns are normally presented in two planes, one horizontal, also known as azimuth plane, and one vertical, also known as elevation plane. The antennas offered by Redline for multi-cell deployment are panel antennas with horizontal patterns of 60° and 90°, and elevation patterns ranging between 9° and 10°.

3.2.8.3 Horizontal Half Power Beamwidth Horizontal Half Power Beamwidth is the aperture angle of the antenna pattern in the horizontal plane where the maximum gain of the antenna is developed. It is considered between angles of the antenna pattern in the horizontal plane where a decrease of intensity from the maximum gain occurs to half of the power or 3 dB.


3.2.8.4 Vertical Half Power Beamwidth Vertical Half Power Beamwidth is the aperture angle of the antenna pattern in the vertical plane where the maximum gain of the antenna is developed. It is considered between angles of the antenna pattern in the vertical plane where a decrease of intensity from the maximum gain occurs to half of the power or 3 dB.

3.2.8.5 Polarization Antenna polarization is the direction of oscillation of the electrical field vector in the electromagnetic wave. This direction can be Vertical, Horizontal or Circular. Redline antennas have Vertical (V) and Horizontal (H) polarization. When selecting the antenna type it is important to choose the proper polarization as any single antenna only carries one polarization, V or H.

3.2.8.6 Return Losses This parameter specifies how well all the radio signals being transferred to the antenna are accepted or rejected by the antenna impedance, or in other words, how good the transfer of power is developed over the antenna. This parameter should be no less than 14 dB (or VSWR of 1.5) over the entire frequency band of the antenna operation typically centered at 3.5 GHz.

3.2.8.7 Downtilt Antenna downtilt can help in the mitigation of intra-system interference. Downtilting is done electrically or mechanically. For Redline antennas, downtilting is mostly done mechanically. The amount of downtilt to apply depends on the antenna height above ground (AGL) and ultimately on the antenna height above average terrain (HAAT) within the coverage area. The main antenna pattern to analyze the effect of the downtilt is the elevation pattern. The analysis of downtilt has, in general, three points of the pattern elevation, the lower and upper 3 dB points and the center of the main beam. These points are analyzed in relation to the ground, where they theoretically touch a flat earth, defining three distances: Lower 3B Distance, Main Beam Distance and Upper 3 dB Distance. The key effect of mechanical downtilt applied to the antenna is reducing the level of energy in the adjacent cell, which aims to concentrate the main beam within the coverage area so that the upper beam still can

provide sufficient signal strength to the outer subscribers in the fringe of the coverage area.

Horizon

Flat EarthLower 3 dB Distance

Upper 3 dB Distance

Main Beam Distance

HA

AT

Figure 11: Downtilting: lower 3dB, main beam, and upper 3 dB distances

The following are typical values of downtilt effect for the AN100 system with Redline-recommended antennas: HAAT = 30 m 90 Degree antenna, Vertical BW= 9 deg Radio Horizon = 22.58 Km


Downtilt Lower 3dB Km Main Lobe Km Upper 3dB Km 0 0.39 22.58 Over Radio Horizon 1 0.31 1.72 Over Radio Horizon 2 0.26 0.85 Over Radio Horizon 3 0.23 0.58 Over Radio Horizon 4 0.19 0.43 Over Radio Horizon 5 0.18 0.34 3.44 6 0.16 0.29 1.14

Table 6: Downtilt effects; 90º antenna, vertical BW 9º HAAT = 30 m 60 Degree antenna, Vertical BW= 10 deg Radio Horizon = 22.58 Km

Downtilt Lower 3dB Km Main Lobe Km Upper 3dB Km 0 0.34 22.58 Over Radio Horizon 1 0.29 1.72 Over Radio Horizon 2 0.24 0.85 Over Radio Horizon 3 0.21 0.58 Over Radio Horizon 4 0.19 0.43 Over Radio Horizon 5 0.18 0.34 Over Radio Horizon 6 0.16 0.29 1.72

Table 7: Downtilt effects, 60º antenna, vertical BW 10º

Figure 12: Effect of mechanical downtilt on a 90º Kathrein antenna:

A few notes on mechanical downtilt:

• The Maximum practical gain reduction that can be practically obtained is in the range of 6 dB. • The horizontal beam widens with the increase of downtilt.


• Resulting gain reduction depends on the azimuth angle. This effect cannot be easily modeled in the network planning.

• For some special locations (hilltops or extremely high buildings) a very high degree of downtilt may be required. For these cases it is important to consider that the vertical pattern has a new lobe known as first upper side lobe that can reach, by the same downtilt effect, other neighbor cells of the system, contributing to an increase in undesired intra-system interference.

3.2.9 Preliminary Coverage Planning Using the Link Budget Tool For the purposes of preliminary link budget and coverage analysis, Redline offers specialized software—the Link Budget Tool, available at its partner site at the following location:

http://partners.redlinecommunications.com/file.php?/linkBudget%201.09.zip. This tool is configured with typical AN100 and RedMAX throughput and sensitivity parameters and can be used in order to establish a preliminary reference for site coverage, as a starting point. The tool also has built-in support for the 802.16 propagation channel model for NLOS known as Erceg (see section 3.2.2.1, Empirical Path Loss Models), as well as LOS or OLOS calculation features. Using the AN100 and AN100U thresholds, the tool calculates a single cell size based on three types of NLOS and terrain conditions, typical in urban or suburban environments, antennas and other RF conditions. The Erceg model is available for base station antenna heights between 10 to 80 m, subscriber antenna height between 2 and 10 m and range up to 10 km. The model is adjusted for 3.5 GHz operation The signals provided by the tool can be considered as average signals for the type of NLOS conditions and other parameter selected. The standard deviation for this model varies between 8 and 10 dB. Inter-cell interference, NLOS fading and other frequency-related analyses are beyond the scope of this calculator; for large multi-cell deployments these calculations should be performed with specialized software.


Figure 13: Redline Link Budget tool

As described in section 3.2.3, Fading in NLOS Environment, the fading calculation for these conditions is different from the typical PTP microwave fading and depends on the conditions of the NLOS environment, mostly the scattering and reflection properties of the medium, the shadowing effects of buildings, trees, moving objects, ground reflections and atmospheric effects. Because it involves complex mathematical algorithms, the calculation of NLOS fading factors is best done using RF propagation tools where the fading factor takes into account the particular conditions of the network including the clutter and terrain topography (NLOS conditions).

3.2.10 Site selection considerations When planning for a multi-cell installation, the target coverage area determines the distance between cells. Cell size is mostly defined by the terrain type, clutter conditions, and the height of SC and SS antennas above ground. Other factors that affect the cell size are subscriber density and traffic. Once marketing data are available, the target areas should be analyzed in detail. A candidate site list, mentioned in section 4.1.2, Network Assessment, should be put together at this point. As a general rule, base station site locations should be in the center of the marketing target areas to offer the best throughputs to the surrounding customers. The candidate sites should have available towers, water towers or rooftops for antenna mounting. Depending on building height, trees and clutter in the coverage area, antennas may need to be mounted typically at 80 to 170 feet AGL. A good practice is to try to mount the SC antenna at least 40 feet above the tree level in the surrounding area. Collocation of the antennas with other radio communications services is feasible, however it is always important to


conduct a site survey exercise as explained in section 2.4.3, Detailed Site Survey, in order to determine potential interactions with other services. In some cases where many other services are co-located in the same site, a noise floor verification across the entire 3.5 GHz band (spectrum analysis) may be necessary. In other, more complex cases one study of carrier intermodulation may be required before any deployment can be done. There is no single definition for all these analyses; they should be conducted by experienced professional installers on site. In order to guarantee minimum antenna deflection, base station antenna mounting should be carefully planned; the antenna should be prepared to withstand worst-case winds, depending on the area wind conditions throughout the year.

3.2.11 Capacity Planning Capacity planning of an 802.16 broadband network requires the analysis of the system’s traffic demand and supply factors. This process involves multiple variables such as service classes, user profiles, activity factors, and QoS priorities combined with the real environment conditions of a wireless link which cannot be easily modeled without computer simulations and analysis of statistical factors typical of IP traffic This section introduces the concepts involved in the capacity planning exercise and provides a simplified approach to the traffic analysis of a network as a general guideline for the preliminary stages of the network planning, feasibility studies or budgeting analyses. For real-life deployments it is strongly recommended that a detailed simulation of the traffic characteristics of the network be carried out within an RF software tool, where all the radio propagation effects are considered in the traffic analysis (section 4.2.2 provides information on capacity planning using the Redline-approved tools from CelPlan Technologies). Several publications offer additional in-depth information on the subject of capacity planning, including Ref 11 and Ref 12 in Appendix C.

3.2.11.1 Capacity Planning Steps Every wireless system being designed to offer service within a given geographic area generates three basic design questions:

1. What cell size should be used? 2. How many stations and sectors per cell will be enough to cover the target area? 3. What channel size (bandwidth) in the wireless system should be used?

The process suggested in the following flowchart (Figure 14) can help answer the three main questions of the capacity planning exercise for demand-based systems. This methodology is based on an iterative process, in which two main branches, Base Stations Required and Throughput Demand are calculating basic factors of the capacity planning exercise. These two branches initially are calculated separately but then are interconnected through different false–true questions in the cycle that goes through several iterations until a final satisfactory point is reached for all the key variables.


TOTAL TARGETED SUBSCRIBERS

TOTAL COVERAGE AREA

CELL SIZE SELECTION

BS REQUIRED

BS REQUIRED THROUGHPUT DEMAND

IS THROUGHPUTPER SECTOR

FEASIBLE?

SECTORS PER BS SELECTION

TOTAL NUMBER OF SECTORS

TOTAL THROUGHPUT DEMAND

THROUGHPUT PER SECTOR

SUBSCRIBERS PER SECTOR

BS , SECTORS AND THROUHGPUTS

ARE SUBSCRIBERSPER SECTORFEASIBLE?

Yes

No

No

Yes

PROPOSSED SERVICES

THROUGPUT AVAILABILITY CHECK

CAPACITY PLANNING CYCLE

Figure 14: Capacity planning flowchart

3.2.11.1.1 Determining the number of base stations required The main purpose of this branch in the capacity planning flowchart is to determine the number of BSs and the total number of sectors required in the system. This aims to answer the first two of the three main questions that capacity planners are faced with (What cell size should be used? and How many stations and sectors per cell will be enough to cover the target area?).


This is initially done strictly from a geographical and demographics point of view based on a choice of cell size and number of sectors per base station. This process is then iterated and refined in connection with the throughput demand and capabilities of the system to supply such demand until both branches of the flow reach satisfactory points for throughput demand per sector and users supported per sector. Determining the number of base stations requires that the following common parameters be defined: § Target market

This can be the global number of subscribers or businesses in an area including: Population: Total population in the coverage area as per census or marketing data. Households: Total number of houses or businesses within the coverage area, as per census or marketing data. Total subscribers: Total number of potential subscribers to be reached.

§ Total coverage area Area to be covered: target areas, in Km2, to be covered in any urban, suburban or rural environment.

§ Market and service objectives Market Penetration: The customer should have in mind a factor of maximum penetration for the target area and future expansion factors expected for the system: Over-subscription rate: an assumption of the number of active/inactive subscribers in the system. Typically between 5 and 10. Activity Factor: Broadband services can be considered as burst-type or dedicated type. Activity factors can vary from very low % figures for burst types in BE traffic up to 100% for dedicated types in cases such as TDM traffic. Loading Factor: Packet delay may increase the traffic during busy hours in the system. To avoid unexpected packet loss as a consequence of peak events it is recommended to use traffic loading factors between 0.7 and 0.9.

§ Total subscribers in the system

The maximum number of subscribers to be managed by the RedMAX system, as a result of market penetration and over-subscription factors applied to the general target market figures.

§ Maximum subscriber density supported (subscribers / Km2)

Subscriber density per area: This factor is the ratio of the maximum number of subscribers per square kilometer within the coverage area that can be supported by the AN100U system based on the maximum number of subscribers that a sector can support in a particular software release. The AN-100U system supports 64 subscribers in Release 1.0, 128 subscribers in Release 1.1, and 512 subscribers in Release 1.2 (assuming one Service Flow per subscriber). The table below, using 128 subscribers per SC (per Release 1.1), shows the maximum subscriber density per square kilometer that the system would support, in typical scenarios: single, 3, 4 or 6-sector configurations and different cell sizes (1 to 10 Km of cell radius).

§ Base Station Arrangement of one or more Sector Controllers and auxiliary equipment placed in one particular location of the network, for serving one cell.

§ Sector Controller A single AN-100 or AN-100U controller servicing one sector of a base station.


Omni 3 Sectors 4 Sectors

Ro (Km) Cell Radius A (Sq Km) Cell AreaMax Density Subs/SqKm

Max Density Subs/SqKm

Max Density Subs/SqKm

1 3.14 40.7 122.23 162.971.5 7.07 18.1 54.32 72.43

2 12.57 10.2 30.56 40.742.5 19.63 6.5 19.56 26.08

3 28.27 4.5 13.58 18.113.5 38.48 3.3 9.98 13.30

4 50.27 2.5 7.64 10.194.5 63.62 2.0 6.04 8.05

5 78.54 1.6 4.89 6.526 113.10 1.1 3.40 4.537 153.94 0.8 2.49 3.338 201.06 0.6 1.91 2.559 254.47 0.5 1.51 2.01

10 314.16 0.4 1.22 1.63

RedMAX rel 1.1 128 subscribers per SC, 1 Service Flow per subscriber

Table 8: AN100U maximum subscriber density supported

§ Cell size selection The cell size can be selected based initially on the subscriber density supported by AN-100U shown in the table above when compared to the subscriber density (subscribers/Km2), including the oversubscription rate, planned for the system upon completing the geographical and demographic analysis. The Cell size is then refined in the process using the results of the throughput demand section in the process flowchart. The number of sectors per base station is also a factor to be determined simultaneously with the cell size under the same criteria of subscriber density supported by AN-100U versus geographical subscriber density. At some point within this iterative process the cell size should also consider the effects of the potential throughput demand offered by the users in a sector and its location within the cell regarding to the base station. Such effects are considered in III - Performing a throughput availability check below.

§ Base stations required This is the total number of BSs in the system as a function of the total subscribers and total coverage area for the cell size selected and throughput demand in the system.

§ Sector per base station This parameter is selected in conjunction with the Cell Size to satisfy the subscriber density supported by AN-100U.

§ Total number of sectors This corresponds to the total number of AN100U SCs required in the system resulting from multiple iterations of cell size and number of sectors per BS in the capacity planning flowchart, considering the total throughput demand of the system.

§ Total subscribers per sector The number of subscriber stations, including SU-Os and SU-Is, in a single sector serviced by one sector controller.

3.2.11.1.2 Determining throughput demand The main purpose of this branch of the capacity planning flowchart (Figure 14) is to calculate the total throughput demand, in Mbps, planned for the network. This task starts from the definition of the planned service classes and GOS to be offered by a RedMAX system:


§ Unsolicited Grant Service (UGS): TDM traffic, VoIP, videoconferencing, needing low delay and jitter. § Real Time Polling (rt-PS): Streaming services class: real time audio and video streaming. § Non-Real-Time Polling Service (nrt_PS): Interactive applications, WWW browsing and Telnet and FTP,

needing a request/response pattern and where round trip delay is important and low error rate transfer § Best Effort Service (BE): E-mail and web browsing. SMS, SNMP, where latency or error rate is less

stringent.

At this point the user should have a clear definition of services and throughputs to be offered by the network.

3.2.11.1.2.1 BE services Once the specific services for the network are defined, a total throughput demand (per uplink and downlink) can be calculated using also the oversubscription factors and the number of potential subscribers per service class. This will determine the total aggregated throughput for the required BE services in the system.

3.2.11.1.2.2 VoIP services For analyzing VoIP services, classic traffic theory can be applied to select the number of circuits and bandwidth required in the wireless portion based on the number of subscribers in a sector that will have VoIP capabilities. A percentage of calls that the system cannot take during a particular period of time is defined as blockage factor. Conversely, the number of calls that can occur in one period of time defines the sector’s traffic figure (erlangs). A typical performance goal for a voice network is to offer a guaranteed probability of blockage of less than 1%. Based on this figure, the number of circuits required in the sector for VoIP traffic can be calculated using Erlang B traffic theory. These topics can be further explored in numerous existing publications on telecommunications traffic, including those listed in Appendix C. When defining VoIP services, two key parameters need to be considered from the system planning perspective: § The specific bandwidth, in Kbps, required per call in the wireless channel. § The maximum number of calls that can be planned across an AN-100U sector.

To select the desired type of codec, users should conduct a comprehensive analysis of quality, convenience, and the type of terminals at the subscriber site that will best support the VoIP services planned. The following table describes two typical VoIP codec implementations and their requirements based on Erlang B traffic concepts.

Codec Kbps Typical Ethernet data rate Kbps G711 64 171.2 G729a 8 39.4

Table 9: Typical bandwidth requirements for VoIP codecs

Maximum simultaneous call capacity per SC

Erlangs at 1% blocking rate

Residential users supported per sector

20 12 163 15 8.1 108

Table 10: Number of VoIP calls per sector and supported users

Using these reference numbers, it is possible to determine the total bandwidth required for VoIP traffic, as well as the total traffic demand of the system.


The next goal in the capacity planning exercise is to determine an average throughput demand for the entire network based on the planned services and the total number of subscribers per service in a sector. Once this factor is determined, it is then fed into the other branch of the capacity planning flowchart (see Figure 14) to calculate the required number of base stations. At the same time, factors output by the “The BS required” process (total number of sectors, subscribers per sector) are fed back into this branch to compute the optimum channel size that will allow the average planned throughput per sector.

3.2.11.1.3 Determining throughput availability and the channel bandwidth A check of throughput availability under the potential demand conditions of the sector will come after this point. The purpose of this step is to verify whether the sector will be able to supply the required throughput demand under the conditions of potential average traffic per user, distribution of subscribers across different modulation schemes, and the AN-100U channel size selected. A particular methodology for this verification can be based on the following concept: As it is impossible to know in advance the exact user locations in the network, a real throughput demand calculation for a sector can be based on the assumption that customer locations and reception conditions are random. Based on this assumption and knowing the average throughput per user, it is possible to: § Make an integration of the total throughput demand across the different available modulation scheme areas

in the cells § Determine whether the expected total throughput demand condition can be satisfactorily (with loading

factors of maximum 80%) managed by the sector controller, according to the channel bandwidth selection (3.5 or 7 MHz).

Data rates as a function of modulation, coding and channel bandwidth, presented in the following table, can be used a guide to determine the optimum channel bandwidth selection.

Modulation Mode FEC

Coding Rate

Uncoded Burst Rate (Mbps)

Typical End to End Ethernet Throughput

(Mbps) * Channel BW (MHz)

3.5

7

3.5

7

BPSK ½ 1.2 2.4 1 2

QPSK ½ 2.4 4.8 2 4

QPSK ¾ 3.6 7.2 3 6

16QAM ½ 4.8 9.6 4 8

16QAM ¾ 7.2 14.4 6 12

64QAM 2/3 9.6 19.2 8 16

64QAM ¾ 10.8 21.6 9 18

Table 11: Data rates as a function of modulation, coding, and channel BW, AN-100U (RedMAX) CP=1/4

*Total average throughput available for up and downlink


3.2.11.2 Capacity Dimensioning Example The following example provides a typical case scenario of capacity calculation.

Case Statement Total Area: 50 km2 Total Target Subscribers: 10,000 Business Subscribers: 20% Residential Subscribers: 80% Over-subscription Rate: 1/5 (business), 1/10 (residential)

Services Planned Business: 512 Kbps DL/ 128 Kbps Residential: 384 Kbps DL/ 128 Kbps

VoIP Codec G729 (8 Kbps); 20 calls per sector This example, following the capacity planning flowchart (Figure 14), starts by determining the number of base stations required.

I - Determining the number of base stations Subscriber Base (A) From the case statement: A = 10,000 Residential users: A1 = 10,000x0.80 = 8,000 Business users: A2 = 10,000x0.20 = 2,000 Total Coverage Area (B) From the case statement: B = 50 km2 Total Subscribers (C) Based on the oversubscription factors we have: Total Residential users: B1 = 8000/10 = 800 Total Business users: B2 = 2000/5=400 Total subscriber load for the system: C = 800 + 400 = 1200 Cell Size Selection: The cell size can be determined after checking the actual subscriber density that can be supported by the AN100U SC: Subscriber Density Factor (D) D = Total Subscribers / Total Area = C/B= 1200 Subscribers / 50 km2= 24 subs/km2 The maximum subscriber density supported by AN-100U indicates that the cell radius should be less than 2.5 km for 4 sectors and less than 3 km for 6 sectors. To cover the target area and based on the system throughput that will be analyzed in the following steps, a cell size of 1 km is chosen for the case. Sectors per Base Station (E) This factor can be selected in close relationship with the number subscribers per sector to be supported. A selection of a 4-sector base station can also be made at this point: E= 4 Based on this selection, the following factors can be determined: Area per Cell (F)


F = 3.14 x (1 km) 2 = 3.14 km2 The Number of Required BSs (G) G = Total Area / Area per cell = B / F = 50 km2/ 3.14 sq-km = 15.92 cells We round this number up: G=16 Other factors that can be deducted at this point are: Total Number of Subscribers per Cell (H) H = Total Subscribers / number of cells = C / G= 1200/16= 75 Total number of Sectors (I) I = number of cells x sectors per BS = GxE= 16x4= 64 Total Number of Subscribers per Sector (J) J = total subscribers per cell/ number of sectors = H/E= 75/4= 18.75. We round this number up to 19.

II - Determining the throughput demand and bandwidth Proposed Services: Business: 512 Kbps DL / 128 Kbps Residential: 384 Kbps DL / 128 Kbps VoIP Codec G729 (8 Kbps), 20 calls per sector. At this point we have: Total Residential users B1 = 8,000/10= 800 Total Business users B2= 2,000/5=400 Total Throughput Demand From the proposed services specified before a complete analysis for up and down link is conducted, as follows: For residential users: Downlik, DL

K DL = 384 Kbps x 800 = 307,200 Kbps

Uplink, UL K UL = 128 Kbps x 800 = 102,400 Kbps

Total aggregated throughput for residential service:

K = K DL + K UL = 307,200 Kbps + 102,400 Kbps = 409,600 Kbps Likewise, for business users:

Downlik, DL L DL = 512 Kbps x 400 = 204,800 Kbps Uplink, UL LUL = 128 Kbps x 400 = 51,200 Kbps

Total aggregated throughput for business services:

L = L DL + LUL = 204,800 Kbps + 51,200 Kbps = 256,000 Kbps


For VoIP services, 20 calls are assumed per sector to cover a maximum of 163 users per sector (to use a conservative number close to rel 1.1 supported subscribers) for a 1% of blocking rate according to Erlang B traffic analysis and assuming and average of 75 mErlangs per call. Under this assumption and considering a typical BW required of 39.4 Kbps for a G729a codec: The VoIP calls per sector will consume in the Downlik, DL: (20 x 39.4 Kbps) = 788 Kbps, requiring a total DL BW of

MDL = Number of Sectors x 788 Kbps = 64 x 788 Kbps = 50,432 Kbps In similar way, the VoIP calls per sector will consume in the Uplink, UL: (20 x 39.4 Kbps) = 788 Kbps, requiring a total UL BW of

MUL = Number of Sectors x 788 Kbps = 64 x 788 Kbps = 50,432 Kbps The Total Aggregated Throughput for VoIP Services (M)

M = (MDL + MUL) = 50,432 Kbps + 50,432 Kbps = 100,864 Kbps From the previous numbers we can now calculate, The Total Aggregated Throughput DL, NDL:

NDL = K DL + LDL + M DL = 307,200 Kbps + 204,800 Kbps + 50,432 Kbps = 562,432 Kbps

Total Aggregated Throughput UL, NUL

NUL = K UL + LUL + M UL = 102,400 Kbps + 51,200 Kbps + 50,432 Kbps = 204,032 Kbps The Total Throughput Demand in the network, N, under the previous calculations is:

N = K+L+M = 409,600 Kbps + 256,000 Kbps + 100,864 Kbps = 766,464 Kbps From this figure other numbers can be calculated, as follows: Throughput per Sector (O) O = total throughput demand/ number of sectors = N/I = 766,464/64= 11,976 Kbps/ sector. Rounded up to 12 Mbps/sector. At this point a consideration of bandwidth selection can be done based on the throughput capabilities of the 3.5 MHz or 7 MHz channel selection and looking for a maximum loading factor of 80% of the throughput capabilities of the system. As per Table 21, for the AN-100U system the expected throughput can be at 18 Mbps peak for 7 MHz or 10.8 Mbps for 3.5 MHz (both for the modulation rate of 64 QAM3/4). Thus, the selection of a 7 MHz channel is the evident choice. At this point we can also have calculated: Average Throughput DL per User (PDL)


PDL = total throughput demand DL / number of users PDL = NDL / C = 562,432 Kbps / 1200= 468.7 Kbps Average Throughput UL per User (PUL) PUL = total throughput demand UL / number of users PUL = NUL / C = 204,032 Kbps / 1200 = 172.52 Kbps Average Total Throughput per User (P) P = PDL + PUL = 468.7 Kbps + 172.52 Kbps = 641.22 Kbps

III - Performing a throughput availability check At this point we have the following key parameters defined Cell Size: 1 Km Throughput demand per sector: 12 Mbps Average throughput DL per user: 468.7 Kbps Average throughput UL per user: 172.52 Kbps Subscriber Stations to be supported per sector (with oversubscription):

19

Up to this point the average throughput demand per sector is only one starting average figure. The analysis of throughput availability intends to make a simulation of real-life conditions that the sector controller will face based on the potential subscriber load and subscriber reception conditions within a cell. This simulation process needs several assumptions in order to make a representation of the sector conditions explained below. Based on the Erceg model C -NLOS scenario and calculations in the Redline Link Budget tool, the following distances can be expected for the downlink, assuming the use of a SU-O outdoor integrated antenna and a typical base station height of 20 m.

Modulation Scheme Cell Radius, Km Area, Km2 % of area 64-QAM 3/4 0.65 1.32665 14.79 64-QAM 2/3 0.83 2.163146 9.33 16-QAM 3/4 1 3.14 10.89 16-QAM 1/2 1.2 4.5216 15.41 QPSK 3/4 1.38 5.979816 16.26 QPSK 1/2 1.45 6.60185 6.94 BPSK 1/2 1.69 8.968154 26.39

Table 12: Modulation schemes available

As it can be seen, three different modulation schemes, 64-QAM ¾, 64-QAM 2/3, and 16-QAM ¾, can be available within the cell size of the case, which is 1 km. Based on this pattern of modulation schemes, a detailed simulation can be carried out to determine throughput demand per user and distributions of modulation schemes. The table below summarizes this simulation:


Sector Users

Link Direction

Rate requested

Kbps

Random RSSI level dBm

Peak Rate available (Mbps)

Channel's share of time needed

Total channel usage

1 Dw 0.468 -79.00 18.20 3% 3%

1 Up 0.169 -79.00 18.20 1% 4%2 Dw 0.468 -83.00 18.20 3% 6%2 Up 0.169 -83.00 18.20 1% 7%

3 Dw 0.468 -79.00 13.66 3% 10%3 Up 0.169 -79.00 13.66 1% 12%

4 Dw 0.468 -83.00 18.20 3% 14%4 Up 0.169 -83.00 18.20 1% 15%

5 Dw 0.468 -79.00 13.66 3% 19%5 Up 0.169 -79.00 13.66 1% 20%

6 Dw 0.468 -83.00 18.20 3% 22%6 Up 0.169 -83.00 18.20 1% 23%

7 Dw 0.468 -79.00 13.66 3% 27%7 Up 0.169 -79.00 13.66 1% 28%

8 Dw 0.468 -83.00 18.20 3% 31%8 Up 0.169 -83.00 18.20 1% 31%9 Dw 0.468 -79.00 13.66 3% 35%

9 Up 0.169 -79.00 13.66 1% 36%10 Dw 0.468 -83.00 18.20 3% 39%

10 Up 0.169 -83.00 18.20 1% 40%11 Dw 0.468 -79.00 13.66 3% 43%

11 Up 0.169 -79.00 13.66 1% 44%12 Dw 0.468 -83.00 18.20 3% 47%

12 Up 0.169 -83.00 18.20 1% 48%13 Dw 0.468 -79.00 13.66 3% 51%

13 Up 0.169 -79.00 13.66 1% 52%14 Dw 0.468 -83.00 18.20 3% 55%14 Up 0.169 -83.00 18.20 1% 56%

15 Dw 0.468 -79.00 13.66 3% 59%15 Up 0.169 -79.00 13.66 1% 61%

16 Dw 0.468 -83.00 18.20 3% 63%16 Up 0.169 -83.00 18.20 1% 64%

17 Dw 0.468 -79.00 13.66 3% 68%17 Up 0.169 -79.00 13.66 1% 69%

18 Dw 0.468 -83.00 13.66 3% 72%18 Up 0.169 -83.00 13.66 1% 73%

19 Dw 0.468 -83.00 20.40 2% 76%19 Up 0.169 -83.00 20.40 1% 77%

Table 13: Throughput distribution simulation across the sector

The analysis conducted and summarized in the table above shows a maximum channel utilization of 77%, which is within the expected sector loading of 80%. Any other combinations of random RSSIs can also be tested at this point for verification. The throughput distribution simulation is based on the following assumptions: Random RSSI level: This column shows random signal levels that each subscriber may have based on the available modulation schemes within the selected cell size. In this case the signal thresholds corresponds to the 7 MHZ channel selected and the available modulation schemes within 1 Km, 64-QAM ¾, 64-QAM 2/3 and 16-QAM ¾.


Peak Rate Available: This field shows the peak rate for each modulation scheme as per the channel size selected and signal thresholds, in this case 7 MHz. Channel’s Share of time needed: This column shows the percentage of time, during which the user will utilize he total sector’s throughput resource. This computation is made based on the total throughput offered by each modulation scheme, the selected channel bandwidth and the average throughput expected from each user for every link direction as determined in the “Throughput demand”. To illustrate with one example, for the signal level of -79 dBm of RSSI and corresponding maximum throughput of 18.2 Mbps offered by the system for 64QAM3/4, an average throughput demand of 0.469 Mbps from each user represents: % of Channel’s share of time = 0.462Mbps / 18.2 Mbps = 2.5 % Total Channel usage This column shows the integration timeshare percentage of the sector’s throughput as a result of the cumulative addition of multiple users in the system. As mentioned, this simulation assumes NLOS-only conditions as NLOS users are considered to a majority and OLOS and LOS users—a minority in the sector. From another perspective, a distribution of NLOS-only users in the simulations offers the most demanding scenario for the throughput analysis in a sector and it can be considered as the worst-case scenario that the sector should be able to support. This completes the exercise with the following answers to the three main questions of capacity planning:

Cell size 1 Km Total number of base stations; Number of sectors per base station

16 base stations; 4 sectors per base station

Channel size (bandwidth) in the wireless system 7 MHz


4 Cell Planning Process Steps This section presents a description of the main concepts and steps of cell planning that take place through several stages. Because the cell design exercise is typically performed using professional RF tools, topics in this section reflect the concepts and chronology of steps of one such tool, the CelPlanner Suite, Redline’s tool of choice for WiMAX system design. CelPlanner is a high-performance RF planning tool covering all the steps of the design cycle, such as coverage and propagation analysis, capacity planning, automatic frequency planning, performance analysis and backhaul system design. The tool is powered by modules developed for the IEEE standards 802.16 OFDM and 802.16 OFDMA. An application note describing the tool setup and the features offered by its WiMAX module can be found at the following Redline Partner site:

http://sales.redlinecommunications.com/docs.php?id=684 The stages of the cell planning process described in the following sections are: Data Collection, Network Planning, Planning Update, Backhaul System Design, and Phase Output. Figure 15 shows the tasks, events and sub-stages within this process in detail.


Candidate Site ListSubscriberServices

CAPEXBudget

ProductSpecification

Data

PropagationCharacterization

Data

Geographical Data,Site Data

Target Areas

Basic Site Selection and Coverage Planning

Capacity Planning

Frequency Planning

Site Surveys DataNetwork AssesmentData

3.5 GHz BWavailable andRegulations

DATA COLLECTION

NETWORK PLANNING

PLANNING UPDATE

PerformanceOK?

Sites Selected sentfor Customer

Feedback

Are sitesviable?

Backhaul System Design

Cell Planning and Backhaul System DesignDocumentation

PHASE OUPUT

Candidate Site ListSubscriberServices

CAPEXBudget

ProductSpecification

Data

Propagation DriveTestData

Geographical Data,Site Data

Target Areas

Basic Site Selection and Coverage Planning

Capacity Planning

Frequency Planning

Site Surveys DataNetwork AssesmentData

3.5 GHz BWavailable andRegulations

DATA COLLECTION

NETWORK PLANNING

PLANNING UPDATE

PerformanceOK?

Sites Selected sentfor Customer

Feedback

Are sitesviable?

Backhaul System Design

Cell Planning and Backhaul System DesignDocumentation

PHASE OUPUT

Topography andClutter database

NO

NO

Figure 15: The Cell Design Process Flow


4.1 Data Collection

4.1.1 Topography and Clutter Database Selection Topography and Clutter databases of the intended coverage area are required to begin the design process. These databases should have enough resolution to provide reasonable accuracy in the propagation predictions. As a general rule, in designs at 3.5 GHz a typical databases resolution of 1 to 4 meters (to include a building database) is good for urban areas. For suburban and rural areas a resolution of 10 meters may be sufficient. The customer should have clearly defined the target areas from their marketing research. These databases are used for both Point -to-Multipoint and Backhaul System Design efforts. At the beginning of the project it should be determined whether such databases for a target country/area exist and can be made available in reasonable timeframes. In some areas of fast-pace development, an update of clutter data may be also necessary for modeling the actual environment. In the case of large deployments or projects involving highly populated areas or buildings, the database resolution that can provide reasonable levels of accuracy in the predictions may become an important decision in the project.

4.1.2 Network Assessment and Site Survey Data During this stage of the design exercise all the data received from previous steps in the project process are consolidated along with Redline’s product specifications. The following Network Assessment and Site Survey data are key at this point for the design: § Geographical Data: Maps, demographics/census data, target areas, market penetration § Subscriber Services: Data, voice, other services, over-subscription rates § Deployment type: demand- or supply-driven § Target areas § Candidate Sites, Site Survey data § RF Network Concept, Backhaul system concept, services defined § Available 3.5 GHz Bandwidth for the project § Local Regulations for 3.5 GHz § Project CAPEX § Red Flag technical issues § Established criteria for Site Lockdown and Cell Planning Design § Site Survey Report § Project Risk assessment

4.1.3 Propagation Model Calibration. Drive test utility. The results of drive tests across the projected area, executed during the Detailed Site Survey stage, are needed at this point in order to perform the calibration of the Propagation Models at 3.5 GHz. The purpose of this stage is to collect real data from the environment where the deployment will take place and to feed this data into the RF tool for calibrating the selected propagation model. The RF tool will typically have a utility or program module where the actual calibration is run once the drive test data is available. This utility analyzes and provides the coefficients that better reflect the propagation across the different type of morphologies or clutter types in the coverage area. For the purpose of propagation model calibration and drive tests, CelPlan Technologies has developed the tool CelSignal for RedMAX. This tool can be used in conjunction with a GPS unit and one omni-directional antenna to collect samples of received signal while driving across a coverage region. This information, in addition to providing immediate information about the coverage of a particular sector, can be graphically analyzed or post-processed with the CelPlanner tool for the calibration process of the propagation models planned for use. CelSignal is expected to be commercially available to Redline Partners and users by the end of Q3 2006.


4.1.4 3.5 GHz Spectrum Channel Allocations The 3.5 GHz band, typically assigned between 3.4 GHz to 3.6 GHz, is a licensed band across all the administrations normally following the ITU (International Telecommunications Union) recommendations and is identified as a preferred band for FWA by CEPT/ERC ("The European Conference of Postal and Telecommunications Administrations” CEPT, European Radiocommunications Committee" (ERC), in Recommendation 13-04. The frequency assignments in this frequency band are allocated following different assignments between 3.4 GHz and 3.6 GHz, and licensed in paired blocks of nx3.5 MHz or nx7 or nx14MHz for TDD or FDD indistinctively with a typical separation of 100 MHz between blocks. Frequency coordination between different operators in a particular region is typically defined per service area by the local regulator. The most typical frequency block assignments across multiple countries are 2x3.5 MHz, 2x7 MHz, 2x14MHz, but also 2X21MHz, 2x42MHz, and up 2x84MHz can be found. In order to facilitate the design process, each customer should research and obtain complete and most current information directly from their local administration. A few guidelines on frequency spectrum requirements for different frequency re-use factors can be found in section 5.2.2, Multi-Cell Frequency Plans . Redline’s AN-100 and AN-100U systems can be used in frequencies from 3.4 GHz and can be set up following different channelization standards for any region. In any case, the AN100 or RedMAX systems have a frequency granularity (or step) of 250 KHz and will adapt to the channelization required by local regulations. Below are formula examples showing potential assignments for 3.5, 7, and 14 MHz* starting at 3403 MHz, supported by Redline products.

Channel Spacing Lower Sub-Band AN100 and AN100U (RedMAX) 3.5MHz fcn = 3401.25 + 3.5*n MHz n = 1 to 27 7 MHz fcn = 3399.5 + 7*n MH z n = 1 to 13 *AN100 only 14 MHz fcn = 3403 + 14*n MHz n = 1 to 6

Table 14: Channelization plan with lower end 3403 MHz for lower sub-band


The following is an example of channel assignments following this frequency allocation plan.

3.5 MHz Channel n Starts Center Ends1 3403.00 3404.75 3406.502 3406.50 3408.25 3410.003 3410.00 3411.75 3413.504 3413.50 3415.25 3417.005 3417.00 3418.75 3420.506 3420.50 3422.25 3424.007 3424.00 3425.75 3427.508 3427.50 3429.25 3431.009 3431.00 3432.75 3434.5010 3434.50 3436.25 3438.0011 3438.00 3439.75 3441.5012 3441.50 3443.25 3445.0013 3445.00 3446.75 3448.5014 3448.50 3450.25 3452.0015 3452.00 3453.75 3455.5016 3455.50 3457.25 3459.0017 3459.00 3460.75 3462.5018 3462.50 3464.25 3466.0019 3466.00 3467.75 3469.5020 3469.50 3471.25 3473.0021 3473.00 3474.75 3476.5022 3476.50 3478.25 3480.0023 3480.00 3481.75 3483.5024 3483.50 3485.25 3487.0025 3487.00 3488.75 3490.5026 3490.50 3492.25 3494.0027 3494.00 3495.75 3497.50

7 MHz Channel n Starts Center Ends1 3403 3406.5 34102 3410 3413.5 34173 3417 3420.5 34244 3424 3427.5 34315 3431 3434.5 34386 3438 3441.5 34457 3445 3448.5 34528 3452 3455.5 34599 3459 3462.5 346610 3466 3469.5 347311 3473 3476.5 348012 3480 3483.5 348713 3487 3490.5 3494

Table 15: Example of channelization plan with lower end 3403 MHz for lower sub-band- 7 MHz channel

A similar channelization may be available for the upper band above 3.5 GHz as a typical paired assignment with a distance of 100 MHz between blocks.


In some European countries the band from 3400 to 3410 is not available for PMP. In this case the recommendation CEPT 1403 sates the channelization plan starting from 3410 MHz and following the frequency assignments determined by the following formulas:

3.5 MHz Channel n Starts Center Ends1 3410.00 3411.75 3406.502 3413.50 3415.25 3410.003 3417.00 3418.75 3413.504 3420.50 3422.25 3417.005 3424.00 3425.75 3420.506 3427.50 3429.25 3424.007 3431.00 3432.75 3427.508 3434.50 3436.25 3431.009 3438.00 3439.75 3434.50

10 3441.50 3443.25 3438.0011 3445.00 3446.75 3441.5012 3448.50 3450.25 3445.0013 3452.00 3453.75 3448.5014 3455.50 3457.25 3452.0015 3459.00 3460.75 3455.5016 3462.50 3464.25 3459.0017 3466.00 3467.75 3462.5018 3469.50 3471.25 3466.0019 3473.00 3474.75 3469.5020 3476.50 3478.25 3473.0021 3480.00 3481.75 3476.5022 3483.50 3485.25 3480.0023 3487.00 3488.75 3483.5024 3490.50 3492.25 3487.0025 3494.00 3495.75 3490.50

Table 16: Example of CEPT1403 channelization plan for lower sub-band-3.5 MHz channel


3.5 MHz Channel n Starts Center Ends1 3510.00 3511.75 3406.502 3513.50 3515.25 3410.003 3517.00 3518.75 3413.504 3520.50 3522.25 3417.005 3524.00 3525.75 3420.506 3527.50 3529.25 3424.007 3531.00 3532.75 3427.508 3534.50 3536.25 3431.009 3538.00 3539.75 3434.50

10 3541.50 3543.25 3438.0011 3545.00 3546.75 3441.5012 3548.50 3550.25 3445.0013 3552.00 3553.75 3448.5014 3555.50 3557.25 3452.0015 3559.00 3560.75 3455.5016 3562.50 3564.25 3459.0017 3566.00 3567.75 3462.5018 3569.50 3571.25 3466.0019 3573.00 3574.75 3469.5020 3576.50 3578.25 3473.0021 3580.00 3581.75 3476.5022 3583.50 3585.25 3480.0023 3587.00 3588.75 3483.5024 3590.50 3592.25 3487.0025 3594.00 3595.75 3490.50

Table 17: Example of CEPT1403 channelization plan for upper sub-band-3.5 MHz channel

7 MHz Channel n Starts Center Ends1 3410 3413.5 34172 3417 3420.5 34243 3424 3427.5 34314 3431 3434.5 34385 3438 3441.5 34456 3445 3448.5 34527 3452 3455.5 34598 3459 3462.5 34669 3466 3469.5 3473

10 3473 3476.5 348011 3480 3483.5 348712 3487 3490.5 3494

Table 18: Example of CEPT1403 channelization plan for lower sub-band-7 MHz channel


7 MHz Channel n Starts Center Ends1 3510 3513.5 35172 3517 3520.5 35243 3524 3527.5 35314 3531 3534.5 35385 3538 3541.5 35456 3545 3548.5 35527 3552 3555.5 35598 3559 3562.5 35669 3566 3569.5 3573

10 3573 3576.5 358011 3580 3583.5 358712 3587 3590.5 3594

Table 19: Example of CEPT1403 channelization plan for upper sub-band-7 MHz channel

The total required spectrum required for each area or project under scope would be the result of a complete system design exercise including capacity and coverage analysis for each case. For the purpose of preliminary considerations customers can choose the frequency spectrum according to the plans and base station configurations of each case as indicated in Table 23: Frequency spectrum required per BS configuration and frequency reuse factors used..

4.1.5 Product Specification Data The following table lists types of AN-100 and AN-100U specifications and identifies where these specifications may be found.

Specification Details

Information on licensed spectrum in the 3.6GHz band

Sections 3.2.2, “Propagation Environment at 3.5 GHz”, and 4.1.4, “3.5 GHz Spectrum Channel Allocations”

Co-channel CI values

Section 3.2.6, C/I, C/N, and CINR

High-level product specifications

AN-100 System User Manual http://64.201.175.138/file.php?/70-00031-02-01-AN-100_User_Manual.zip AN-100U Base Station User Manual http://partners.redlinecommunications.com/file.php?/70-00058-01-00-RedMAX_AN-100U_UserMan.pdf

Radio specifications

AN-100 System User Manual (70-00031-02-01), Appendix 10.2 http://64.201.175.138/file.php?/70-00031-02-01-AN-100_User_Manual.zip AN-100U Base Station User Manual, Appendix 8.2 http://partners.redlinecommunications.com/file.php?/70-00058-01-00-RedMAX_AN-100U_UserMan.pdf

Rx sensitivity values

AN-100 System User Manual (70-00031-02-01), section (appendix) 10.3 http://64.201.175.138/file.php?/70-00031-02-01-AN-100_User_Manual.zip AN-100U Base Station User Manual, Appendix 8.3 http://partners.redlinecommunications.com/file.php?/70-00058-01-00-RedMAX_AN-100U_UserMan.pdf

Antenna specifications

AN-100 Antenna Specifications http://64.201.175.138/file.php?/70-00032-01-00-AN-100_Antenna_Guide.zip

Time Synchronization information

Section 5.2.4, Multi-Cell Synchronization AN-100 System User Manual (70-00031-02-01), section 7.3 http://64.201.175.138/file.php?/70-00031-02-01-AN-100_User_Manual.zip RedMAX Technical Bulletin, GPS Satellite Synchronization http://sales.redlinecommunications.com/file.php?/MB-SC_GPS_installation_Proc-20060629a.pdf


In addition, below are additional specifications on data rates (as a function of modulation, coding and channel bandwidth) based on CP=1/4.

Modulation Mode

FEC Coding

Rate

Uncoded Burst Rate, Mbps Typical End to End Ethernet Throughput, (Mbps)*

Channel BW (MHz)

3.5

7

14

3.5

7

14

QPSK ½ 2.4 4.8 9.6 2 4 8

QPSK ¾ 3.6 7.2 14.4 3 6 12

16QAM ½ 4.8 9.6 19.2 4 8 16

16QAM ¾ 7.2 14.4 28.8 6 12 24

64QAM 2/3 9.6 19.2 38.4 8 16 32

64QAM ¾ 10.8 21.6 43.2 9 18 36

Table 20: Data rates as a function of modulation, coding, and channel BW, AN-100*

Modulation Mode

FEC Coding

Rate

Uncoded Burst Rate

(Mbps)

Typical End to End Ethernet Throughput

(Mbps) * Channel BW (MHz)

3.5

7

3.5

7

BPSK ½ 1.2 2.4 1 2

QPSK ½ 2.4 4.8 2 4

QPSK ¾ 3.6 7.2 3 6

16QAM ½ 4.8 9.6 4 8

16QAM ¾ 7.2 14.4 6 12

64QAM 2/3 9.6 19.2 8 16

64QAM ¾ 10.8 21.6 9 18

Table 21: Data rates as a function of modulation, coding, and channel BW, AN-100U (RedMAX) CP=1/4

*Total average throughput available for up and downlink

4.2 Network Planning This stage defines all the concepts to be applied to the network design, including service classes, cell size according to customer requests and future expansions, base station heights, receiver conditions across the area and target performance. A clear statement on the RF spectrum available for the project should be available at this point.

4.2.1 Site Selection and coverage planning An operator’s goal at this stage is to choose sites that provide the best coverage. Typically, the operator may be faced by one of two possible courses of action:


§ Planning the network based on an existing pool of candidate sites as collected in the Network Assessment phase

§ Determining the best site location by using available data on the terrain (geography) and cost (ownership of land, buildings, towers)

In both cases, an operator uses available data and comes up with a rough estimate of possible performance using RF planning and simulation tools, and based on the results, confirms or modifies the initial set of site locations.

4.2.2 Capacity Planning using the CelPlanner Tool This section outlines the process of capacity planning using the CelPlaner tool. Conceptual information, practical guidelines and an example can be found in section 3.2.11. The capacity analysis, as conducted in the CelPlaner tool, is carried out by using a process of traffic dimensioning, developed by CelPlan particularly for Wireless Broadband and 3G cellular systems. The process of traffic dimensioning is divided into three major blocks, demand characterization, system simulation and performance analysis. The stage of demand characterization determines the total traffic to be offered to a given network (Mbps). It is based in demographics, marketing information and different types of services, traffic patterns and user profiles expected in the coverage area. Once the demand is characterized, the system simulation stage processes this data considering the terrain, propagation coverage and radio network setup in order to assess the system capabilities to support the traffic demand. During the system simulation the following details are evaluated:

• Compatibility analysis (sector controller-subscriber compatible radios) • Link adaptation (using CINR) to obtain scheme and maximum instantaneous data rates • Resources in contention

The simulation analysis produces the following traffic results:

• Reports on users (offered/served/rejected) and throughput • Reports on full, partial (queued), and rejected service results • Results displayed per-sector, per-carrier, and per-service class

Once the simulation is conducted, the system suggests a number of alternatives to satisfy the traffic conditions defined in the demand characterization; this may be a number of carriers or throughput per sector in each base station. Depending on weather or not these conditions may be practical, the designer may accept changes proposed and move to the stage of traffic performance analysis. To assess the effect of the accepted changes on the system, the performance analysis may include different types of predictions, such as those on C/I or system availability.


Error!

Figure 16: CelPlan - Traffic simulation results

4.2.3 Frequency Planning A meticulous frequency planning effort allows more frequency reuse, leading to a lower number of cells in a required coverage area. Also, a well-planned, efficient frequency plan can reduce interference and result in a better quality of the overall wireless network. The process of Frequency Planning is typically executed through the use of an automatic resource planning module within the RF software tool that utilizes sophisticated statistical algorithms to assign the best possible plan based on interference analysis of different scenarios (Site-to-Site, Site-to-Subscribers-in-other-cells, Subscriber-to-other-Sites-in-the-network), and on RF characteristics of the technology, in this case OFDM. Technically it is possible for an operator to manually allocate individual frequencies to radios. However, because a real-life wireless network is never deployed in an ideally flat area with no propagation anomalies, the frequency planning process needs to be least simulated or partially computerized. For the purpose of automatic frequency planning, CelPlan, the RF tool used by Redline for WiMAX cell planning, includes a very strong module, which is a separate program in the suite, called CelOptima. The following screen capture illustrates the multitude and complexity of parameters the tool considers.


Figure 17: CelPlan - Automatic Frequency Planning and Optimization parameters

Upon completion of the frequency planning process, each SC is allocated an individual frequency channel.

4.2.3.1 Frequency Spectrum available The design exercise should have a starting 3.5 GHz frequency spectrum available for each case. This spectrum has to come from the preliminary definitions and agreements with the Customer as a result of the Network Assessment stage, according to the target areas to cover, demographics and services to be offered. During the Frequency Planning section, the designer will setup the RF tool for the allocations within the available band. The results of the design exercise, once the Performance Analysis has been conducted, will determine if the spectrum offered satisfies the objectives of the project. For WiMAX design applications, depending on the project size and project objectives, it is ideal to have paired blocks of the 3.5 GHz spectrum available, i.e., 2 x 7 MHz or 2 X14 MHz or 2X28 MHz, etc, with 100 MHz frequency separation. Although the implementation of the final frequency configuration and required total spectrum will vary from case to case in TDD or FDD applications, having two different blocks in different sections of the spectrum will always offer better isolation options and flexibility in frequencies to be used in each base station. Although the AN100 and AN100U RedMAX line is offered with the capability to cover the entire band of 3.4 to 3.8 GHz, with a frequency granularity (center frequency steps) of 250 KHz, and different configurations of 3.5, 7 or 14 MHz, a particular radio unit (SC or SS transceiver unit) should be checked with Redline Sales Engineers against the spectrum availability and particular application type (TDD or FDD).

4.2.4 Performance Analysis The frequency plan generated in the previous stage should be analyzed from the point of view of system availability and quality of the designed system across the complete coverage area. This stage should provide detailed information, for the entire network, on potential interference or other service degradations that may occur in certain areas, given the spectrum used for the frequency plan and site conditions. For this purpose CelPlan offers a complete set of performance predictions including:


• Type – Time Outage: percentage of the time system is affected – Traffic Outage: traffic affected – Equivalent C/I: maps resulting outage to equivalent C/I

• Geographical Performance Analysis (per pixel) – Control and Traffic Channels – Co-channel, Adjacent Channel, Combined Interference – Downlink, Uplink, Combined Predictions

• System Availability – Sector availability report – Overall system performance

The following figure displays one such performance prediction for Time Outage before and after the Automatic Frequency Planning (AFP) stage.

Figure 18: Figure 20: CelPlan Time Outage Performance Analysis Predictions

4.3 Planning Update During this step, following the process flowchart, information on the selected sites, as well as antenna types and heights, is presented to the Customer to reconfirm viability from a technical and economical perspective. Variations that may impact the viability of the presented plan of sites are documented by the Redline Partner or customer and are sent to the network designer who adjusts the plan as required and according to the Site Lockdown criteria stated in the network assessment.

4.4 Backhaul System Design This purpose of this stage is to design a wireless backhaul system that will provide the required bandwidth to each site in the network.


The Backhaul concept, PTP, PMP and frequency bands discussed also in the Network Assessment can be re-evaluated at this point and its viability confirmed after all the network sites and antenna conditions have been finally determined.

Figure 19: CelPlan - Backhaul Design window

Figure 20: CelPlan Backhaul Design Results per link


4.5 Cell Planning Process Output Upon completion of the cell planning process, an operator is equipped with the following key pieces of the overall network plan: § Maps of coverage § RSSI values for uplink and downlink § C/I values for uplink and downlink § LOS details § BS sites, information on customers, radios to be used

Figure 21 and Figure 22 below are samples of typical plots and details of the design process:

Figure 21: Plot of region coverage indication signal level, modulation schemes and coverage


Figure 22: Detailed Network and Site Configuration with frequency plan


5 Cell Deployment Depending on the density and number of subscribers, distribution and size of the area, desired amount of bandwidth to each subscriber, expansion plans and a range of other technical factors, an RF planner might favor a particular deployment scenario for a certain area. Redline systems are designed and tested to operate in most common deployment scenarios using certified antennas and complying to conditions referred to in the description of each scenario.

5.1 Single Cell, Multiple Sectors Signal quality and consequently a subscriber’s performance in a sector is affected by multiple characteristics including cell size, transmit power level of sector controller and subscriber stations, details of antenna gain, beam width, height and mechanical tilt, as well as environmental parameters affecting the fade margin. Certain condition such as the ones mentioned below may encourage and RF planner to choose a multi-sector deployment scenario:

§ Low density – Subscribers are spread over a large area and a single sector cannot serve all. § High density – Too many subscribers are located in one sector and maximum number of subscribers per

SC is near. § Capacity – The maximum capacity of the sector controller is reached.

If coverage of all subscribers at an acceptable penetration rate using sectors located sufficiently far from one another (with zero or negligible interference) is possible, then such a network can be treated as a set of independent single sectors, in which case co-channeling (reuse of the same frequency) may be practiced with minimal concern. This will allow an operator to efficiently operate a geographically dispersed network using a single or a couple of frequency channels (extra channel for backhauling of traffic). Otherwise, attention should be paid to the details of positioning, choice of frequency, antenna polarization, and sector controller synchronization in order to minimize the effects of intra- and inter-cell interference. The main goal in a multi-sector deployment is to achieve optimal coverage and penetration while maintaining efficiency in spectrum usage.

5.1.1 Co-located Sectors: Deployment Considerations The term co-location applies to a number of sector controllers positioned in the same site constituting an isolated cell. Redline systems are designed and tested to perform in co-location with virtually no impact on services, provided the following guidelines are followed:

Synchronization All co-located sector controllers are required to be synchronized. Typically one sector controller acts as a master feeding the clocking signal to other sector controllers while a second sector controller acts as a spare (Backup Slave) in case the master malfunctions. All other sector controllers are configured as slaves and retrieve clocking data from the Master. Failure to synchronize even one active sector controller in the cell may degrade or disrupt services in other sectors. To read more about the sector controller synchronization configuration and cabling, refer to the product user manual. Frequency Choice Where possible, it is recommended to choose as many center frequencies as the number of co-located sectors. However, spectrum costs in the licensed 3.4-3.8 GHz band force an optimum use of the frequencies. Reuse of the same or adjacent channel in the cell is allowed but in order to minimize degradation of CINR due to interference from neighboring sectors, it may be necessary to cross-polarize antennas and maintain a certain distance between the antennas.


Antenna Polarization Co-channeling in the same cell should only be used with 180º separation (back to back) and certified cross-polarized antennas. See a few examples of cross-polarized multi-sector scenarios later in this section. When reusing the frequency at the same cell, the use of alternate polarization is beneficial since it offers a source of interference isolation for subscribers that are closely located to the BS and that might be in LOS or OLOS conditions. The effect of alternate polarization for farther subscribers in NLOS conditions cannot be as effective because of the likelihood of polarization rotation or de-polarization that may occur in different points of the NLOS coverage zone due to multiple reflections of the electromagnetic wave. Antenna Separation Desired separation requirements between co-located sector antennas (Redline’s Flat panel antennas) are as follows: Back to back: 6 ft Side to side: 3 ft

6ft (1.8m)

3ft (0.9m)

Figure 23: Physical antenna separation specifications

Tilting Depending on the BS antenna height assumed within 150 ft AGL, two to four degrees of mechanical tilting of antennas can reduce the effects of potential co-channel and adjacent channel interference in any closer cell, but it might slightly reduce the sector coverage. In later sections the down tilt effects will be covered with more detail. Frame Size All co-located sector controllers must be configured to use the same wireless frame size (e.g., 10 ms). Uplink/Downlink Ratio All co-located sector controllers must be configured to the same “DL ratio” value (e.g., 54%). Failure to follow these guidelines will have a negative impact on a portion or the entire traffic of one or a number of co-located sectors.

5.1.2 Four-Sector Scenario Figure 24 below illustrates the top view of a sample 4-sector, 2-frequency cell with 90° cross-polarized antennas. Co-channel sectors should use antennas with different polarization (vertical vs. horizontal) and follow the guidelines for co-located sectors above. F1 and F2 may be adjacent channels when using certified antennas.


S1 S2

S3S4

F1 H Pol.

F2 H Pol.

F1V Pol.

F2V Pol.

S1: Sector 1S2: Sector 2...

F1: Frequency 1F2: Frequency 2...

Figure 24: An example of a four-sector, two-frequency cell

The set of diagrams below illustrates the expected maximum downlink modulation scheme to be achieved by LOS subscribers in 3 km and 6 km range with 4-sector 2-frequency cells in a flat terrain. Antennas are 30 meters above ground level (AGL). Note that actual environment and terrain effects could impact these results. This four-sector, two-frequency scenario was installed and simulated by Redline.

5.1.3 Six-Sector Scenario Figure 25 below shows the top view of a sample 6-sector, 3-frequency cell with 60-degree cross-polarized antennas.


F3V Pol.

F2V Pol.

F1H Pol.

F1V Pol.

F3H Pol.

F2H Pol.

S2

S3

S4

S5

S6

S1

S1: Sector 1S2: Sector 2...

F1: Frequency 1F2: Frequency 2...

Figure 25: An example of a six-sector, three-frequency cell

As shown in this figure, co-channel sectors have to use antennas with different polarization (vertical vs. horizontal) and all sectors must be synchronized. F1, F2 and F3 could be adjacent channels using Redline’s certified antennas. This six -sector, three-frequency cell scenario was installed and simulated by Redline.


5.1.4 Single Cell Simulations The following illustrations show, as a general reference, the effect of cell size and environment on the downlink modulation scheme received by subscribers in different conditions of OLSO or NLOS, analyzed for the two types of scenarios: § Six Sectors, three frequencies, two polarities § Four Sectors, two frequencies, two polarities.

5.1.4.1 Six Sector, 3 Frequencies, OLOS Conditions: Environment: Suburban. Base Station: 30m AGL Simulation distance: 7 km Rx antenna: SUO-IA Rooftop installation, height: 12 m AGL



5.1.4.2 Six Sector-3 Frequencies-Base – NLOS Conditions: Environment: Residential Base Station: 30m AGL Simulation distance: 2.8 km Rx antenna: SUO-IA Under the eave, height: 3 m AGL


5.1.4.3 Six Sector-3 Frequencies-Base Station- NLOS Conditions: Environment: Residential Base Station: 40m AGL Simulation distance: 3.2 km Rx antenna: SUO-IA Under the eave, height: 3 m AGL


5.1.4.4 Six Sector- 3 Frequencies-Base Station - NLOS Conditions: Environment: Residential Base Station: 50m AGL Simulation distance: 3.6 km Rx antenna: SUO-IA Under the eave, height: 3 m AGL


5.1.4.5 Four Sectors - 2 Frequencies-OLOS Conditions: Environment: Suburban. Base Station: 30m AGL Simulation distance: 7 km Rx antenna: SUO-IA Rooftop installation, height: 12 m AGL


5.1.4.6 Four Sectors - 2 Frequencies-NLOS Conditions: Environment: Residential Base Station: 30m AGL Simulation distance: 2.5 km Rx antenna: SUO-IA Under the eave, height: 3 m AGL






5.2 Multiple Cells This section introduces in-depth conceptual and practical information on using Redline’s AN-100 and RedMAX products in multi-cell environments.

5.2.1 Multi-Cell Frequency Reuse Concepts

5.2.1.1 Reuse Patterns N In order to consider possible arrangements of base stations in different distance and frequency configurations, and to be able to analyze potential interference interactions when using co-channel or adjacent frequency channels, the hexagonal system, widely used for analysis of Cellular Communications, is adopted for our WiMAX case. The geometry of this system facilitates the simulation of different frequency reuse patterns in a geographic area and serves as a model for interference analysis between sites. There are other graphical methods of representing this type of analysis, such as the rectangular system, in which the coverage areas are assumed rectangular and installed in adjacent cells. However, the hexagonal system is a more practical way of representing the real scenarios in the field. A typical reuse pattern is defined by the number of cells it utilizes and is named N=X. A cluster is a set of cells that have a particular reuse pattern and that can be reproduced across a design region. As an illustration, typical patterns of three to seven cells are represented in the following figures, identified as N=3, N=4, N=7.

3

2

1

2

1

2

3

1

3

3

2 2

3

1 1

1

1

2

3

Figure 26: Reuse pattern N=3

4 3

3

12

3

1

4

4

2

3

2

4

1

1

1

1

2

1

Figure 27: Reuse pattern N=4


4

5

1

6

7

2

3

1

7

5

1

64

5

3

1

7

2

4

5

3

162

4

31

7

2

1

6

1 1

1 1

1 1

Figure 28: Reuse Pattern N=7

5.2.1.2 Reuse Distance D The following figure shows the definition of the variables used in the following paragraphs.

D

D= Re-use DistanceR= Re-use Distance

Factor

R= D/Ro

Ro

Ro

D

Ro

Figure 29: Frequency reuse variables

Associated to each reuse pattern there is a reuse distance, defined as D, which is the geometrical distance between two cells with the same identification in the pattern. It is commonly expressed either as a function of the cell radius R0, D= 2R0, D= 3R0 etc, or though an expression known as Reuse Distance Factor R, R=2, R=3, etc, which is the normalized expression of D to the cell radius R0. In either case the distance D or R can be obtained for a particular reuse pattern through geometric deduction based on the hexagonal shapes. The following are the Reuse distance factors corresponding to different Reuse patterns:


N RReuse Pattern Reuse distance Factor

2 23 3.14 3.467 4.6

Figure 30: Reuse patterns and distance factors

To help illustrate this concept, the following figure presents the distances from the center cell as a function of the cell radius R0.

22

22

20

2

64

4

6

64

46

4

4

6

32 32

32

3232

3272

6

72

7272

72

72

72

727272

72

72

Figure 31: Distances from the center cell as a function of the cell radius R0

The frequency reuse capabilities of a communications system are based on the Carrier-to-Interference (C/I) ratio of the particular modulation type in use in the cellular system. When trying to reuse the same frequency across a particular area, the key factor to determine is the minimum distance for a particular modulation scheme where that frequency can be reused, given a particular pattern. In order to determine this minimum distance, a mathematical analysis of desired signal, C, to the total undesired or interfering signal, I, coming from the neighbor cells, should be conducted, based on the hexagonal system. To begin the analysis, the following expression relates the total Carrier to Interference C/I of a cellular system, based on the previous definitions:

∑=

=I

k

K

k

I

CIC

1

In the same way, the total C/I ratio of a system can be correlated to the distance between correspondent cells involved in the interference analysis, based on the following equivalent expression:


∑=

−

−

=I

k

K

k

D

RIC

1

0

γ

?

In this expression, γ is the path loss exponent of the environment. This factor can be better understood through the following Path Loss general expression, where Pr is the received power, Pt is the transmitted power, and K a constant factor.

γDK

PP

Lt

r 1==

In this expression γ can be assumed equal to 2 for LOS. In this case, for NLOS, it is assumed as 4. Continuing with the previous analysis, C/I, as defined in the expression above, can be described as the ratio of distances, desired (C) to summation of all undesired signals (I), in a particular interfered point in the cellular system:

CI1

I2I3

I4I5

Ii

R0

D4

D3

D2

D1

Di

D5

Figure 32: C/I as the ratio of distances

In the above figure, C is the desired signal at a specific interfered point in the system, and I1 to Ii are the interferences coming from the neighbor cell s of the pattern. D1 to Di are the correspondent distances from the cells to the interfered point under analysis

5.2.1.3 Achievable C/I per Reuse Pattern Based on this analysis, the C/I factors corresponding to a particular reuse pattern N can be deduced by mathematical simulation using available geometry and RF parameters of the cellular system. Alternatively, a general or simplified approach may be used. For example, C/I estimates may be based on worst-case interfered points in a particular pattern configuration. This analysis is done assuming a predefined arrangement of sector antennas per cell site. The selection of the worst case interfered points in each scenario will


depend on the type of antenna pattern and front-to-back ratios in the configuration of each base station. Typical antenna patterns in our case are 60, 90 or 120 deg, corresponding to 6, 4 or 3 sectors per base station. To simplify the concepts explained above and using the expression below, an approximation for a cellular system using omnidirectional antennas will yield:

40

61

−

=

DR

IC

for N=7 cell pattern, D/R0 = 4.6

4

6.41

61 −

=

IC

=75.16 or IC

= 18.7 dB

The detailed deduction of the achieved C/I for other reuse systems using panel antennas, which is beyond the scope of this document, can be done following the same concepts (see Ref 5 in Appendix C).

5.2.1.4 C/I and Reuse Factors The next table shows C/I values as a function of frequency reuse distance R and the modulation scheme applicable to each case. This table is based on typical C/I figures for an AN100/RedMAX six-60 degree sector base station configuration.

Modulation Scheme AN100 C/I, typical AN100 C/I, worst-case Recommended Reuse Distance, greater than

64QAM ¾ 24.4 34 6R 64QAM 2/3 22.7 32 6R 16QAM ¾ 18.2 28 4R 16QAM ½ 16.4 26 4R QPSK ¾ 11.2 21 3R QPSK ½ 9.4 19 3R BPSK ½ 6.4 16 2R

Table 22: C/I as function of frequency reuse distance and modulation scheme

CASE 1 refers to C/I ratios where the carrier signal is above the same thresholds (>10 dB). CASE 2 refers to C/I ratios required when the carrier signal is close to the sensitivity threshold of the receiver at the particular modulation scheme. It can be concluded that distance reuse factors as low as 2 can be used for modulation schemes such as BPSK, and frequency reuse factors of no lower than 6 are required for 64QAM. It should be understood that the concept of frequency reuse of 2 can only apply to an application where the SS installation conditions of a particular cell are all in NLOS conditions against its base station or SCs in the neighbor cells. To better understand the concept of frequency reuse distance, consider Figure 33, which shows multiple concentric or co-located modulation schemes in a typical 802.16 base station. In a typical scenario where the 64QAM coverage area is only a percentage of the total QPSK area (not higher than 15%), reuse factors as low as R=2, corresponding to the lowest modulation scheme QPSK, can simultaneously satisfy the required reuse distance of R=6 for the highest modulation scheme such as 64 QAM.


16QAM

QPSK

QPSK Cell

64QAM Cell

64QAM

QAMQPSK

QAMQAMQAM

QPSKQPSKQPSK

RR

RDR

RDR

64

6406464

0

>>

=

=

−

−

QPSKD

QPSKR −0

Figure 33: Frequency reuse of co-located modulation schemes

5.2.2 Multi-Cell Frequency Plans This section provides multi-cell frequency planning guidelines for deployments involving different reuse factors and applicable to different subscriber scenarios. Frequency plans in this section are introduced from a conceptual point of view. A subsequent section, 5.2.6 Frequency Plan Simulations, presents the same plans using optimized distribution of frequencies per base station for minimum interference. The building blocks of these plans were selected from the basic scenarios discussed in Cell Deployment (section 5.1, Single Cell, Multiple Sectors). The objective is to help Redline’s customers to get started with a WiMAX project implementation. Multi-cell frequency planning is about optimum use of the frequency spectrum. In this regard network planners should consider using the most efficient frequency reuse factor for each case but always keeping in mind the tightly related system performance parameters, such as system BER. Because the configurations in this section are based on several assumptions that may differ from specific customer cases, the analysis, selection and field application of the presented plans and concepts are the customer’s responsibility. Redline strongly recommends that for large deployments the frequency planning analysis and system design be done with the help of a professional RF software tool that uses appropriate topographic and clutter databases of the design region and performs a detailed and simultaneous analysis of interference, frequency plans, capacity and coverage. Basic Assumptions for all implementations 1. GPS Synchronization is used in every BS in the network, as explained in section 5.2.4, Multi-Cell Synchronization. 2. The path loss exponent of the NLOS environment (see 3.2.7.2, Assumptions and Propagation Concepts) is between 3 and 5 or according to the channel models used. 3. Frequency reuse concepts per modulation scheme as explained in previous sections. 4. Uniform coverage area types (urban, suburban or rural) across the implementation area.


5. Consistent cell sizes used across the implementation area, i.e., same modulation schemes used in every cell across the implementation area.

5.2.2.1 Frequency Plans for LOS-OLOS/NLOS Receive Conditions The scenario for this plan considers any uniform environment (Urban, Suburban or Rural) with a combination of subscribers in LOS, OLOS and regular NLOS conditions. Four cases are presented with each offering different capacity conditions and reuse characteristics: § Frequency Plan 1: N=4, 60 degree sectors, 12 frequencies § Frequency Plan 2, N=4, 90 degree sectors, 8 frequencies § Frequency Plan 3, N=3, 60 degree sectors, 9 frequencies § Frequency Plan 4, N=3, 90 degree sectors, 6 frequencies

In the figures below, the following notation is used: § Frequency channels in the 3.5 GHz are identified as numbers 1..12 § Channel 1 and Channel 2 are adjacent in the frequency spectrum

The application of N=3 or N=4 will depend on the ratio of the planned LOS-OLOS/NLOS subscribers and inter-cell distance. As a general guide, the configuration N=4 will provide the highest isolation between cells and should be used if the ratio LOS-OLOS/NLOS is higher than 0.5 (or 50%).


1

1V

3H

5V1H

5H

3V

2

2V

4H

6V

2V

6H

4V

3

7V

9H

11V

7H

11H

9V

4

8V

10H

12V

8H

12H

10V

Antennas per site: 6x60degFrequencies Required: 12

(3 frequencies per site)

BW REQUIREDFor 3.5 MHz Channel: 12X3.5 MHz = 42 MHzFor 7.0 MHz Channel: 12X7.0 MHz = 84 MHz

For 14.0 MHz Channel: 12X14.0 MHz = 168 MHz

4

8V

10H

12V

8H

12H

10V

3

7V

9H

11V

7H

11H

9V

2

2V

4H

6V

2V

6H

4V

1

1V

3H

5V

1H

5H

3V

N=4 => D=3.46R

N=4 CLUSTERFrequencies Used:

Cell 1: 1,3,5Cell 2: 2,4,6Cell 3: 7,9,11Cell 4: 8,10,12

1 3

342

34

1

12

3

2

14

4

4

4

2

4

Figure 34: Frequency Plan 1: N=4, 60º Sectors, NLOS/LOS-OLOS Rx Conditions


N=4 => D=3.46R

1

1V

1H 3V

3H

2

2V

2H 4V

4H

35V

5H 7V

7H

4

6V

6H 8V

8H

1

1V

1H 3V

3H

2

2V

2H 4V

4H

3

5V

5H 7V

7H

4

6V

6H 8V

8H

Antennas: 4x90degFrequencies Required: 8(2 frequencies per site)



2 4

413

41

2

23

4

3

21

1

1

1

3

1

N=4 CLUSTERFrequencies

usedCell 1: 1,3Cell 2: 2,4Cell 3: 5,7Cell 4: 6,8



32

13

21

2

3

1

3

3

2 23

1 1

1

12

N=3CLUSTER

Frequenciesused:

Cell 1:1,4,7Cell 2: 2,5,8Cell 3: 3,6,9

Antennas per site: 6x60degFrequencies Required: 9(3 frequencies per site)

BW REQUIREDFor 3.5 MHz Channel: 9X3.5 MHz = 31.5 MHzFor 7.0 MHz Channel: 9X7.0 MHz = 63 MHz


2

2V

5H

8V

2H

8H

5V

N=3 => D=3.1R

1

1V

4H

7V1H

7H

4V

3

3V

6H

9V

3H

9H

6V

3

3V

6H

9V

3H

9H

6V

2

2V

5H

8V

2H

8H

5V

3

3V

6H

9V

3H

9H

6V

2

2V

5H

8V

2H

8H

5V

2

2V

5H

8V

2H

8H

5V



1

1V

1H 4V

4H

2

2V

2H 5V

5H

3

3V

3H 6V

6H

Antennas: 4x90degFrequencies Required: 6(2 frequencies per site)

BW REQUIREDFor 3.5 MHz Channel: 6X3.5 MHz = 21MHzFor 7.0 MHz Channel: 6X7.0 MHz = 42 MHz


N=3CLUSTERFrequencies used

Cell 1: 1,4Cell 2: 2,5Cell 3: 3,6

2

2V

2H 5V

5H

3

3V

3H 6V

6H

3

3V

3H 6V

6H

2

2V

2H 5V

5H

2

2V

2H 5V

5H

32

13

21

2

3

1

3

3

2 23

1 1

1

12


5.2.2.2 Frequency Plans For NLOS Receive Conditions The scenario for this plan considers any uniform environment, Urban, Suburban or Rural, with subscribers having regular NLOS reception conditions, i.e., all subscriber antenna paths to the base station are obstructed. Interference rejection in these and similar N=2 plans is currently being field tested for implementation and general viability; a future release of this document will capture the results. § Frequency plan 5, N=2, 90 degree Sectors, 4 frequencies § Frequency plan 6, N=2, 90 degree Sectors, 2 frequencies – theoretical plan only- § Frequency plan 7, N=2, 60 degree Sectors, 6 frequencies § Frequency plan 8, N=2, 60 degree Sectors, 3 frequencies


Antennas: 4x90degFrequencies Required: 4


For 14.0 MHz Channel:4X14.0 MHz = 56 MHz

A1V

2V 3V

4V

B

1V

2V 3V

4V

C

1V

2V 3V

4V

G

1V

2V 3V

4V

F

1V

2V 3V

4V

D

1V

2V 3V

4V

E

1V

2V 3V

4V

N=2

Figure 38: Frequency Plan 5: N=2, 90º Sectors, NLOS Rx Conditions, 4 Frequencies.


B

1V

3V

5V

2V

6V

4V

A

1V

3V

5V

2V

6V

4V

G

1V

3V

5V

2V

6V

4V

C

1V3V

5V

2V

6V

4V

D

1V

3V

5V

2V

6V

4V

F

1V

3V

5V

2V

6V

4V

E

1V

3V

5V

2V

6V

4V

ANTENNAS: 6X 60degFrequencies Required: 6


For 14.0 MHz Channel: 6X14.0 MHz =84 MHz

Figure 39: Frequency Plan 7: N=2, 60º Sectors, NLOS Rx Conditions, 6 Frequencies


As a summary of the previous alternatives, the following table captures the main characteristics of each plan:

6331.59336 Sectors

844212346 Sectors

42216234 Sectors

56288244 Sectors

6331.59333 Sectors

844212343 Sectors

BW Required per plan

7 MHz

BW Required per plan 3.5 MHz

Frequencies per Plan

Frequencies per BS

Re-use Factor

Plan

6331.59336 Sectors

844212346 Sectors

42216234 Sectors

56288244 Sectors

6331.59333 Sectors

844212343 Sectors

BW Required per plan

7 MHz

BW Required per plan 3.5 MHz

Frequencies per Plan

Frequencies per BS

Re-use Factor

Plan

Table 23: Frequency spectrum required per BS configuration and frequency reuse factors used.

5.2.3 Cell Size Recommendations The size of a base station cell depends on the customer’s marketing target area and capacity objectives, as well as the AN100 and AN100U capabilities. From coverage and frequency reuse standpoint, it is recommended to try to keep the same cell size across the deployment region assuming a common terrain and clutter characteristics across the area. The minimum distance between cells should be defined based on the practical coverage area in each environment type in accordance with the antenna heights used. For cases where the design is targeting to service only upper modulation levels (16QAM and up) in the coverage area, the design demands of a careful selection of the cell size vs. BS antenna height and receiver antenna conditions in order to meet all the requirements previously set for C/I. In this case the design should also include an analysis of upstream and downstream signal levels, C/I, SC and SS power levels and antenna downtilt to minimize any potential effects of interference with other cells. In such cases the frequency reuse distances for each modulation scheme and frequency plans still should follow the principles explained earlier in this document.

5.2.4 Multi-Cell Synchronization An important feature for effectively deploying multiple AN100 and AN100U systems is the multi-cell GPS Time Synchronization, which controls the timing of the transmission and reception periods required in half duplex operation. The benefits of this feature include optimum frequency reuse in the system, controlled interference and spectrum efficiency. For Multi-cell deployment Redline recommends using the ACUTIME 2000TM GPS unit from TrimbleTM. This unit provides a precise (with an accuracy of 50 ns) one pulse-per-second (PPS) output signal that can be used for clock synchronization. The unit should be installed in each base station site as the source of signal timing for every sector controller in the site, using the SYNC-IN SMA ports on the AN100/AN100U systems. For this purpose Redline has made available a complete kit including the GPS unit and the required hardware to interface with AN100/AN100 sector controllers. Notes on the setup and use of the GPS unit:


1. The ACUTIME 2000 TM unit should be installed according to the Trimble Acutime 2000 user guide instructions.

2. All base station SCs, as well as SCs in the immediate neighborhood cells should be setup to the same Frame Size value (e.g., FD 10ms).

3. All the sector controllers must be configured to the same “UL/DL ratio” value (e.g., 75%). 4. The “Cell Range” parameter of the sector controller is the TX/RX and RX/TX gap limiter and should be set

to simulate the real inter-cell distance of contiguous cells in the field for optimum synchronization. For example, “Cell Range” should be set to 4 Km for Inter-cell distance of 8 Km in two contiguous cells of 4 Km.

Interfacing and using the RedMAX product with external GPS units is the subject of the Redline Technical bulletin:

http://sales.redlinecommunications.com/file.php?/MB-SC_GPS_installation_Proc-20060629a.pdf At this time, Redline is conducting additional tests of the Synchronization feature in multi-cell deployments with AN100U. This document will capture additional recommendations as they become available.

5.2.5 Application Examples The following examples illustrate the appropriate use of frequency allocations.

5.2.5.1 Example 1 In a particular system, the user has the following 7 MHz plan available and two closely located sites to deploy:

Channel Center Frequency From To 1 3.5 3.4965 3.5035 2 3.507 3.5035 3.5105 3 3.514 3.5105 3.5175 4 3.521 3.5175 3.5245 5 3.528 3.5245 3.5315 6 3.535 3.5315 3.5385

7 3.542 3.5385 3.5455 A simple alternative for the frequency distribution for the two sites might be as showed below:

A

1V

3H

5V

1H

5H

3V

Site A

B

2V

4H

6V

2H

6H

4V

Site B

Figure 40: Example 1, 7MHz plan in two sites

In the above figure, the frequency channels are identified as 1, 2, 3, 4, 5 and 6. The channel polarity is defined as V or H; for example, 6H means Channel 3.535 MHz in H Polarization. The distance between the two BSs in this case is not a major concern as the two sites are using different frequencies.


5.2.5.2 Example 2 In a more complex scenario using 6 sectors BS and 12 channels of 7 MHz, consisting of 12x7= 84 MHz, a larger system is planned to be deployed. In this particular case, the system uses a frequency reuse pattern of N=4 and a reuse distance of D=3.46R, as shown in the table below.

n Center Frequencies,

MHz Assignment

1 3406.5 F1

2 3413.5 F2

3 3420.5 F3

4 3427.5 F4

5 3434.5 F5

6 3441.5 F6

7 3448.5 F7

8 3455.5 F8

9 3462.5 F9

10 3469.5 F10

11 3476.5 F11

12 3483.5 F12 Below is a suggested frequency distribution plan (N= 4 and D=3.46R) based on the available channels. This plan uses:

Antennas Per site: 6x60deg Frequencies Required: 12 (3 frequencies per site)

The plan can be repeated across the entire project region, regardless of the final cell size selected. BW REQUIRED: For 7.0 MHz Channel: 12X7.0 MHz = 84 MHz


1

1V

3H

5V

1H

5H

3V

2

2V

4H

6V

2V6H

4V

3

7V9H

11V

7H

11H

9V

4

8V

10H

12V

8H

12H

10V

4

8V

10H

12V

8H

12H

10V

3

7V

9H

11V

7H

11H

9V

2

2V

4H

6V2V

6H

4V

1

1V

3H

5V

1H

5H

3V

Figure 41: Example 2, Frequency plan N=4 and D=3.46R


5.2.6 Frequency Plan Simulations This section presents simulations of different frequency plans optimized using the Redline Link Simulator.

5.2.6.1 About the Redline Link Simulator Redline uses a link simulator for the purpose of analyzing the interference effects of different frequency re-use patterns, antennas, and RF conditions typical in 802.16 systems. The tool works based on different scenarios or pre-arranged frequency plan distributions and can use different propagation models for LOS or NLOS. It can graphically display the predicted co-channel plus adjacent channel interference effects and signal propagation conditions within a specific area. Different NLOS channel models can also be simulated to emulate typical receiver installation conditions such as Rooftop, Under-the-Eave (residential), Under-the-Eave (suburban) and more. The tool bases the interference analysis on different settings of frequency arrangements and number of sectors, known as scenarios. The frequencies of each scenario can be purposely rotated or optimized in different conditions in order to achieve the minimum levels of interference between sites. This type of frequency distributions can be manipulated externally in text files. The interference analysis is conducted based on AN100/AN100U specifications, the specified SC and SS receiver conditions and antenna patterns, and can use different resolutions according to the cell size, from 50m to 8m in the 4 Km cell size case. Note that the results do not consider terrain variations or different clutter types per area.

Figure 42: Redline Link Simulator Parameters


Figure 43: Redline Link Receiver Simulation Parameters

5.2.6.2 Simulation Parameters Based on the characteristics of Redline’s AN100 and AN100U products, the figures and tables below present several optimized alternatives to the plans presented previously. They use the same concepts and frequency re-use patterns introduced earlier but the frequencies per site have been rotated per base station in a specific way in order to achieve the lowest interference level in the patterns. The simulation results consist of three pieces of information per each frequency plan: § A figure showing the “scenario” where the base stations are displayed with the different sector

configurations (six or four sectors per base station), frequencies, and antennas used § A figure showing the “zones covered with the highest rate of modulation” where every modulation scheme

has a resulting percentage of the simulated area including the coverage range. § A table with the frequencies and antenna polarities per plan.

The simulations were conducted using the following parameters:

Antenna Types

EA_SA15_90_3.56V: European Antenna, 90 degrees, 15.2 dBi, 3.56 GHz vertical antenna pattern used. EA_SA15_90_3.56H: European Antenna, 90 degrees, 14.7 dBi, 3.56 GHz horizontal antenna pattern used. EA_SA17_60_3.56V: European Antenna, 60 degrees, 17.1 dBi, 3.56 GHz vertical antenna pattern used. EA_SA16_60_3.56H: European Antenna, 60 degrees, 16 dBi, 3.56 GHz horizontal antenna pattern used. SUO-IA: Redline Outdoor Integrated SS antenna, 30 degrees, 14 dBi

Base station height: 30 m BW: 7 MHz channel Fade Margin: 10 dB Propagation environment: Under the eave (Residential)


Roof height 6m AGL (two-story building) Receiver antenna height: 3m AGL Cell Radius: Variable 2-3 Km Resolution: 50m

The following table displays the receiver parameter setup window. The data used can be considered as typical for AN100 or AN100U:

Figure 44: Link Simulator Receiver Parameters

5.2.6.3 Optimized Frequency Plans Following the nomenclature established in 5.2.2, Multi-Cell Frequency Plans, this section presents optimized versions (suffix O) of the different frequency plans that were previously discussed. Example, Frequency plan 1O denotes an optimized version of the frequency plan 1. In the tables below, the following notation is used: § Frequency channels in the 3.5 GHz are identified as numbers 1..12 § Channel 1 and Channel 2 are adjacent in the frequency spectrum

5.2.6.3.1 Frequency Plans for NLOS+LOS Conditions As mentioned earlier, the application of N=3 or N=4 will depend on the ratio of the planned LOS/NLOS subscribers and inter-cell distance. There is no single formula to define which one to select; however, as a general guide, the configuration N=4 will provide the highest isolation between cells, and hence the least level of interference. As a very general guideline, N=4 should be used if the ratio LOS/NLOS subscribers is higher than 0.5 (or 50%). N=3 can be seen as another alternative for the same case, but is recommended for deployments where there are fewer LOS


subscribers in the area. In any case, the customer should assess the conditions of each subscriber and its potentiality of causing interference in neighbor cells. This section contains four frequency plans: § Frequency Plan 1O: N=4, 60 degree sectors, 12 frequencies. § Frequency Plan 2O, N=4, 90 degree sectors, 8 frequencies § Frequency Plan 3O, N=3, 60 degree sectors, 9 frequencies § Frequency Plan 4O, N=3, 90 degree sectors, 6 frequencies

5.2.6.3.1.1 Frequency Plan 1O: N=4, 60º Sectors, 12 Frequencies

Figure 45: Frequency Plan 1O, Scenario


Figure 46: Frequency Plan 1O, percentage of area per modulation rate

BS Sector1 Pol Sector2 Pol Sector3 Pol Sector4 Pol Sector5 Pol Sector\6 Pol 1 7 V 9 V 11 V 7 H 9 H 11 H 2 12 V 8 V 10 V 12 H 8 H 10 H 3 2 V 4 V 6 V 2 H 4 H 6 H 4 1 V 3 V 5 V 1 H 3 H 5 H 5 8 V 10 V 12 V 8 H 10 H 12 H 6 2 V 4 V 6 V 2 H 4 H 6 H 7 5 V 1 V 3 V 5 H 1 H 3 H 8 11 V 7 V 9 V 11 H 7 H 9 H 9 5 V 1 V 3 V 5 H 1 H 3 H 10 7 V 9 V 11 V 7 H 9 H 11 H 11 8 V 10 V 12 V 8 H 10 H 12 H 12 11 V 7 V 9 V 11 H 7 H 9 H 13 6 V 2 V 4 V 6 H 2 H 4 H 14 11 V 7 V 9 V 11 H 7 H 9 H 15 1 V 3 V 5 V 1 H 3 H 5 H 16 7 V 9 V 11 V 7 H 9 H 11 H 17 12 V 8 V 10 V 12 H 8 H 10 H 18 11 V 7 V 9 V 11 H 7 H 9 H 19 6 V 2 V 4 V 6 H 2 H 4 H

Table 24: Frequency Plan 1O, frequencies and antenna polarities per base station






BS Sector1 Pol Sector2 Pol Sector3 Pol Sector4 Pol 1 3 V 7 V 3 H 7 H 2 8 V 4 V 8 H 4 H 3 2 V 6 V 2 H 6 H 4 1 V 5 V 1 H 5 H 5 4 V 8 V 4 H 8 H 6 2 V 6 V 2 H 6 H 7 5 V 1 V 5 H 1 H 8 7 V 3 V 7 H 3 H 9 5 V 1 V 5 H 1 H 10 3 V 7 V 3 H 7 H 11 4 V 8 V 4 H 8 H 12 7 V 3 V 7 H 3 H 13 6 V 2 V 6 H 2 H 4 7 V 3 V 7 H 3 H 15 1 V 5 V 1 H 5 H 16 3 V 7 V 3 H 7 H 17 8 V 4 V 8 H 4 H 18 7 V 3 V 7 H 3 H 19 6 V 2 V 6 H 2 H






BS Sector1 Pol Sector2 Pol Sector3 Pol Sector4 Pol Sector5 Pol Sector6 Pol 1 7 V 1 V 4 V 7 H 1 H 4 H 2 2 V 5 V 8 V 2 H 5 H 8 H 3 9 V 3 V 6 V 9 H 3 H 6 H 4 2 V 5 V 8 V 2 H 5 H 8 H 5 3 V 6 V 9 V 3 H 6 H 9 H 6 8 V 2 V 5 V 8 H 2 H 5 H 7 3 V 6 V 9 V 3 H 6 H 9 H 8 9 V 3 V 6 V 9 H 3 H 6 H 9 1 V 4 V 7 V 1 H 4 H 7 H 10 8 V 2 V 5 V 8 H 2 H 5 H 11 1 V 4 V 7 V 1 H 4 H 7 H 12 9 V 3 V 6 V 9 H 3 H 6 H 13 7 V 1 V 4 V 7 H 1 H 4 H 14 8 V 2 V 5 V 8 H 2 H 5 H 15 1 V 4 V 7 V 1 H 4 H 7 H 16 9 V 3 V 6 V 9 H 3 H 6 H 17 1 V 4 V 7 V 1 H 4 H 7 H 18 8 V 2 V 5 V 8 H 2 H 5 H 19 7 V 1 V 4 V 7 H 1 H 4 H







BS Sector1 Pol Sector2 Pol Sector3 Pol Sector4 Pol 1 4 V 1 V 4 H 1 H 2 2 V 5 V 2 H 5 H 3 6 V 3 V 6 H 3 H 4 2 V 5 V 2 H 5 H 5 3 V 6 V 3 H 6 H 6 5 V 2 V 5 H 2 H 7 3 V 6 V 3 H 6 H 8 6 V 3 V 6 H 3 H 9 1 V 4 V 1 H 4 H 10 5 V 2 V 5 H 2 H 11 1 V 4 V 1 H 4 H 12 6 V 3 V 6 H 3 H 13 4 V 1 V 4 H 1 H 14 5 V 2 V 5 H 2 H 15 1 V 4 V 1 H 4 H 16 6 V 3 V 6 H 3 H 17 1 V 4 V 1 H 4 H 18 5 V 2 V 5 H 2 H 19 4 V 1 V 4 H 1 H



5.2.6.3.2 Frequency Plans for NLOS Receive Conditions These plans assume any uniform environment, Urban, Suburban or Rural, with subscribers having regular NLOS reception conditions. This deployment type implies that any subscriber antenna path to the base station is obstructed and there are no Rooftop or LOS subscribers that may be able to cause interference to a neighbor cell. Interference rejection for N=2 plans is currently being field tested for implementation and general viability; a future release of this document will capture the results. This section contains the following four frequency plans: § Frequency plan 5O, N=2, 90 degree Sectors, 4 frequencies § Frequency plan 6O, N=2, 90 degree Sectors, 2 frequencies § Frequency plan 7O, N=2, 60 degree Sectors, 6 frequencies § Frequency plan 8O, N=2, 60 degree Sectors, 3 frequencies





BS Sector1 Pol Sector2 Pol Sector3 Pol Sector4 Pol 1 1 V 2 H 3 V 4 H 2 2 V 1 H 4 V 3 H 3 3 V 4 H 1 V 2 H 4 4 V 3 H 2 V 1 H 5 3 V 4 H 1 V 2 H 6 2 V 1 H 4 V 3 H 7 3 V 4 H 1 V 2 H 8 4 V 3 H 2 V 1 H 9 3 V 4 H 1 V 2 H





NOT RECOMMENDED – SIMULATION SHOWING HIGH INTERFERENCE


BS Sector1 Pol Sector2 Pol Sector3 Pol Sector4 Pol 1 1 V 2 V 1 H 2 H 2 2 V 1 V 2 H 1 H 3 1 V 2 V 1 H 2 H 4 2 V 1 V 2 H 1 H 5 2 V 1 V 2 H 1 H 6 1 V 2 V 1 H 2 H 7 2 V 1 V 2 H 1 H






BS Sector1 Pol Sector2 Pol Sector3 Pol Sector4 Pol Sector5 Pol Sector6 POl


1 3 V 1 H 6 V 4 H 2 V 5 H 2 4 V 6 H 1 V 3 H 5 V 2 H 3 5 V 2 H 4 V 6 H 1 V 3 H 4 1 V 3 H 5 V 2 H 4 V 6 H 5 4 V 6 H 1 V 3 H 5 V 2 H 6 5 V 2 H 4 V 6 H 1 V 3 H 7 1 V 3 H 5 V 2 H 4 V 6 H







BS Sector1 Pol Sector2 Pol Sector3 Pol Sector4 Pol Sector5 Pol Sector6 Pol 1 1 V 3 V 5 V 1 H 3 H 5 H 2 5 V 3 V 1 V 5 H 3 H 1 H 3 3 V 1 V 5 V 3 H 1 H 5 H 4 1 V 3 V 5 V 1 H 3 H 5 H 5 5 V 3 V 1 V 5 H 3 H 1 H 6 3 V 1 V 5 V 3 H 1 H 5 H 7 1 V 3 V 5 V 1 H 3 H 5 H



Appendix A Glossary

backhaul In wireless network technology, to transmit voice and data traffic from a cell site to a switch, i.e., from a remote site to a central site. Also, to transmit data to a network backbone, or to get data to a point from which it can be distributed over a network.

coaxial cable A type of wire in which a center conductor is surrounded by a concentric outer conductor. Also called "coax".

dB Decibel, a logarithmic unit of intensity used to indicate power lost or gained between two signals. Named after Alexander Graham Bell.

dBd Gain in decibels referenced to a standard half-wave dipole antenna. This is a more realistic reference to antenna gain.

dBi Gain in decibels referenced to an isotropic radiator. An isotropic radiator is a theoretical antenna with equal gain to all points on isotropic sphere. 2.15 dBi = 0 dBd

dBm Decibel referenced to 1 milliwatt into a 50 Ohm impedance 0 dBm = 1 mW

kBps Kilobytes per second, unit of data rate measurement, 1,000 bytes per second or 8,000 bits per second. Example: 30 kBps

kHz Kilohertz, unit of frequency measurement, 1,000 periods per second. Example: 455 kHz

Kbps Kilobits per second, unit of data rate measurement, 1,000 bits per second. Example: 128 Kbps

mW Milliwatt, one thousandth (1/1000) of a Watt, used to indicate received or transmitted power.

EIRP Effective Isotropic Radiated Power, actual power transmitted in the main lobe after taking in account all cable losses and antenna gain. Based on an isotropic antenna.

Fade Margin The difference, in dB, between the magnitude of the received signal at the receiver input and the minimum level of signal determined for reliable operation. Higher the fade margin, the more reliable the link will be. The exact amount of fade margin required depends on the desired reliability of the link. Fade margin is often referred to as "thermal" or "system operating margin".

FWA Fixed Wireless Access

Free Space Loss Attenuation, in dB, of a RF signal's power as it propagates through open space.

Fresnel Zone An elliptical region surrounding the line-of-sight path between transmitting and receiving antennas. Must be obstruction free-for a microwave radio link to work properly.

Front-To-Rear (Back) Ratio

Antenna measurement that is determined from the peak power difference, in decibels, between the main radiation lobe at 0° (front of an antenna) and the strongest rearward lobe (back of the antenna). Higher the ratio, the more directional the antenna is.

GHz Gigahertz, unit of frequency measurement, 1,000,000,000 periods per second. Example: 2.4 GHz

Hz Hertz, the basic unit of frequency measurement, cycle per second. Example: 60 Hz

MHz Megahertz, unit of frequency measurement, 1,000,000 periods per second. Example: 147.075 MHz


Impedance The complex combination of resistance and reactance, measured in Ohms (50 typically). Impedance must be matched for maximum power transfer.

Line-of-Sight When the transmit and receive antennas can physically see each other.

Mbps Megabits per second, unit of data rate measurement, 1,000,000 bits per second. Example: 1.544 Mbps

Multipath When the RF signal arrives at the receiving antenna after bouncing through several paths. Significantly degrades the received signal power.

OFDM Orthogonal Frequency Division Multiplexing, a transmission technique whereby a single transmitter transmits on many different orthogonal (independent) frequencies.

RF Radio Frequency, electromagnetic radiation between 10 kHz and 300 GHz.

Bandwidth The width of a signal on the radio spectrum. The greater the signal's bandwidth, the more frequency space it occupies, and the stronger the signal needs to be to overcome noise.

Path Loss Free space loss of RF power plus any power loss due to link path obstructions, poor antenna height, and link distance.

Polarization The polarity of a radio signal's electric field. Transmit and receive antennas must have the same polarity for maximum receive power.

PMP Point to multipoint system

Radiation Fields There are three traditional radiation fields in free space as a result of an antenna radiating power.

Near-field, also called the reactive near-field region is the region that is closest to the transmitting antenna and for which the reactive field dominates over the radioactive fields.

Fresnel zone, also called the radiating near-field, is that region between the reactive near-field and the far-field regions and is the region in which the radiation fields dominate and where the angular field distribution depends on distance from the transmitting antenna.

Far-field, or Rayleigh distance, is the region where the radiation pattern is independent of distance from the transmitting antenna.


Appendix B Additional Frequency Reuse and Interference Diagrams




Appendix C References § Ref 1 – “Broadband Fixed Wireless Access Network Planning for high-speed Internet services—

Methodology”, John Berry ATDI Ltd. § Ref 2 – “Channel Models for Fixed Wireless Applications”, IEEE 802.16 Broadband Wireless Access

Working Group, http://ieee802.org/16. § Ref 3 – “Comparison of Empirical Propagation Path Loss—Models for Fixed Wireless Access Systems”,

V.S. Abhayawardhana, I.J. Wassell, D. Crosby, M.P. Sellars, M.G. Brown. § Ref 4 – “Designing CDMA 2000 Systems”, CelPlan Technologies, Inc., 2004 John Wiley &Sons, Ltd. § Ref 5 – “Mobile Cellular Telecommunications”, William C.Y. Lee, McGraw Hill. § Ref 6 – “Additional enhancements to Interim Channel Models for G2 MMDS Fixed Wireless Applications

(IEEE 802.16.1c -00/49)”, IEEE 802.16 Broadband Wireless Access Working Group, http://ieee802.org/16. § Ref 7 – “Redline Deployment Process Flow”, Redline Communication Inc.,

http://partners.redlinecommunications.com/file.php?/Redline%20Deployment%20Process%20Flow-V1-R6.pdf.

§ Ref 8 – “Network Assessment Guide“, Redline Communication Inc., http://partners.redlinecommunications.com/file.php?/P1%20Network%20Assessment%20Guide-V1-R4.pdf.

§ Ref 9 – “RedMAX System Implementation Guide”, Redline Communication Inc., http://partners.redlinecommunications.com/file.php?/RedMAX%20System%20Implementation%20Guide-V1-R1.pdf.

§ Ref 10 – “Traffic analysis and design of wireless IP networks”, Toni Janevski, 2003 Artech House. § Ref 11 – White papers: “Deployment Considerations for Fixed Wireless Access in License Bands” and

”Business Case Models for Fixed Broadband Wireless Access based on WiMAX Technology and the 802.16 Standard”, WiMAX Forum, www.wimaxforum.org

§ Ref 12 – “Nationwide implementation of a WiMAX mobile access network”, www.analysis.com, http://www.analysys.com/default_acl.asp?Mode=article&iLeftArticle=1935

Documents

P5 Cell Planning and Design Guide_V1-R2