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BSNL LDCE EXAM 2015 LDR Consumer Mobility
ExamKart www.examkart.testpress.in Page 1
BSNL LDCE EXAM 2015
Last Day Revision [LDR] Guide
Consumer Mobility
Created By ExamKart
BSNL LDCE EXAM 2015 LDR Consumer Mobility
ExamKart www.examkart.testpress.in Page 2
Index
Sr No Chapters 1 Chapter 1 : Cellular Concepts & Modulation Techniques 2 Chapter 2: GSM Mobile Communication 2G 3 Chapter 3: GPRS ,EDGE 4 Chapter 4: GSM 3G 5 Chapter 5: RF Planning & Drive Test 6 Chapter 6: Mobile VAS 7 Chapter 7: MIN [Mobile Intellegient Network] 8 Chapter 8: Roaming & International Roaming 9 Chapter 9: Project Vijay
10 Chapter 10: Sancharsoft 11 Chapter 11: Overview of CDMA 2000 1x & EVDO 12 Chapter 12:WI-FI & Wimax 13 Chapter 13: Mobile Number Portability 14 Chapter 14: Earthing & Power Plant 15 Chapter 15: Charging and Billing in GSM/CDMA 16 Chapter 16:HSPDA,LTE,LTE-A 17 Chapter 17:Intelligent Network in Mobile Communication 18 Chapter 18: Security Features in GSM/CDMA and its Lawful interception
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Chapter 1 - Cellular Concepts & Modulation Techniques
Cell: A cell is the basic geographic unit of cellular system. Cells are base stations
transmitting over small geographic areas that are represented as hexagons.
A group of cells is called a cluster. No frequencies are reused in a cluster.
Types of Cell
Macro Cell: is a cell in a mobile phone network that provides radio coverage served by a
high power cellular base station (tower). Generally, macrocells provide coverage
larger than microcell. Macrocell base stations have power outputs of typically tens of
watts.
Micro cell :is a cell in a mobile phone network served by a low power cellular base
station (tower), covering a limited small area such as a mall, a hotel, or a transportation
hub
Pico cells :are small cells whose diameter is only few dozen meters; they are used
mainly in indoor applications.It can cover e.g. a floor of a building or an entire building,
or for example in shopping centers or airports,which means that there are several radio
antenna placed within one pico cell.
Umbrella cells:A layer with micro cells is covered by at least one macro cell, which
can cover large areas
Features of Digital Cellular Systems:
Small cells : A cellular system uses many base stations with relatively small coverage radii (on the order of a 100 m to 30 km).
Frequency reuse: The spectrum allocated for a cellular network is limited. As a result
there is a limit to the number of channels or frequencies that can be used. For this
reason each frequency is used simultaneously by multiple base-mobile pairs. This
frequency reuse allows a much higher subscriber density per MHz of spectrum than
other systems.
Small, battery-powered handsets : enables the use of small, battery-powered
handsets with a radio frequency that is lower than the large mobile units used in
earlier systems
Performance of handovers: In cellular systems, continuous coverage is achieved by
executing a handover (the seamless transfer of the call from one base station to
another) as the mobile unit crosses cell boundaries.
Cells using the same channel set are called co-channel cells
Cell clustering :Radio channels can be reused provided the separation between cells containing the same channel set is far enough apart so that co-channel interference can be kept below acceptable levels most of the time.
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Reuse Factor: The number of channel sets is called K. K is also called the reuse factor. Thus K is the number of cells in a group where there is no re-use of available frequency resources and also all the available frequency resources have been exhausted such a group of cells is called a cluster.
Valid values of K can be found using equation (where i and j are integers): K=i+j+i*j
As long as the ratio, Frequency reuse distance / Cell radius = D/R is greater than some
specified value, the ratio Received radio carrier power / Received interferer radio carrier
power =C/I will be greater than some given amount for small as well as large cell sizes when
all signals are transmitted at the same power level
Relationship between K and D/R
Relationship between K and Network Performance
If K increases, then the co-channel interference decreases, and so the performance increases
Relationship between K and Cell Capacity If K increases, the number of frequencies per set (and so per cell) decreases, and so the call capacity per cell. Capacity/Performance Trade-offs If K increases, then performance increases
If K increases, then call capacity decreases per cell Techniques to reduce interference and enhance spectral efficiency Power Control Use if directional Antennas (3 sector configuration) Mobile Assisted Handover (MAHO).
Imp Modulation Techniques
a. Amplitude Shift Keying (ASK)
b. Frequency Shift Keying (FSK)
c. Phase Shift Keying (PSK)
d. Minimum Shift Keying (MSK) : MSK is a special form of binary CPFSK. The signal has a
constant envelope. MSK is attractive because it has relatively compact spectrum and
its out-of-band performance is better than FSK.
Bandwidth efficiency ()
If a digital link transmits R bits/s utilizing BW Hz of RF bandwidth then the bandwidth efficiency () is measured by the channel throughput defined as follows:
= R/BW bits/s/Hz
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Two level Modulation system 1 bit/s/Hz
Four level Modulation system = 2 bit/s/Hz
Eight level Modulation system = 3 bit/s/Hz
Comparison of Macro Cellular and Micro Cellular systems
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Chapter 2 - GSM 2G GSM Frequencies
1. GSM-900 mobile system A. Uplink Frequency (mobile station to BTS) : 890 MHz - 915 MHz B. Downlink (BTS to mobile station): 935 MHz - 960 MHz. C. Duplex Spacing:45 Mhz
2. GSM-1800 mobile system A. Uplink Frequency (mobile station to BTS) : 1710 MHz- 1785 Mhz B.Downlink (BTS to mobile station): 1805 MHz - 1880 MHz C.Duplex Spacing: 95 MHz.
A GSM system comprises of three major subsystems 1. Network subsystem 2.Radio subsystem 3.Operation support subsystem GSM Network Structure In the GSM system, the network is divided into the following partitioned areas.
GSM service area: is the total area served by the combination of all member countries where a mobile can be serviced.
PLMN service area: There can be several PLMN area within a country, based on its size.
MSC service area: In one PLMN there can be several MSC/VLR service areas.
Location area: There are several LAs within one MSC/VLR combination. A LA is a part of the MSC/VLR service area in which a MS may move freely without updating location information to the MSC/VLR exchange that control the LA
Cells: LA is divided into many cells. A cell is an identity served by one BTS.
Mobile Station [MS]
The MS includes radio equipment and the man machine interface (MMI) that a
subscriber needs in order to access the services provided by the GSM PLMN.
Functions of MS Transmit and receive voice and data over the air interface of the GSM system. Signal processing function of digitizing, encoding, error protecting, encrypting, and
modulating the transmitted signals.
SIM Card GSM subscribers are provided with a SIM card with its unique identification at the very beginning of the service. The SIM is a removable SC, the size of a credit card, and contains an integrated circuit chip with a microprocessor, random access memory (RAM), and read only memory (ROM).
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International Mobile Subscriber Identity (IMSI) :An IMSI is assigned to each authorized GSM user. It consists of a mobile country code (MCC), mobile network code (MNC), and a PLMN unique mobile subscriber identification number (MSIN).
Temporary Mobile Subscriber Identity (TMSI) :A TMSI is a MSC-VLR specific alias that
is designed to maintain user confidentiality.
Mobile Station Roaming Number (MSRN): The MSRN is allocated on temporary basis when the MS roams into another numbering area. The MSRN number is used by the HLR for rerouting calls to the MS. It is assigned upon demand by the HLR on a per-call basis.
International Mobile Equipment Identity (IMEI) :The IMEI is the unique identity of the equipment used by a subscriber by each PLMN and is used to determine authorized (white), unauthorized (black), and malfunctioning (gray) GSM hardware. An IMEI is never sent in cipher mode by MS.
White List: contains those IMEIs that are known to have been assigned to valid MSs. This is the category of genuine equipment.
Black List: contains IMEIs of mobiles that have been reported stolen.
Gray List: contains IMEIs of mobiles that have problems (for example, faulty software and wrong make of the equipment).
Base Station System [BSS] :The BSS is a set of BS equipment (such as transceivers and
controllers) The radio equipment of a BSS may be composed of one or more cells. A BSS
may consist of one or more Base Station.
Base Transreceiver Station [BTS]: is a network component that serves one cell and is
controlled by a BSC.
Functions of BTS
The primary responsibility of the BTS is to transmit and receive radio signals from a
mobile unit over an air interface.
Transcoding to bring 13-kbps speech to a standard data rate of 16 kbps and then
combining four of these signals to 64 kbps is essentially a part of BTS, though, it can be
done at BSC or at MSC.
Transcoder/Rate Adapter Unit (TRAU): The TRAU is the equipment in which coding
and decoding is carried out as well as rate adoption in case of data.
Base Station Controller [BSC]:The BSC is connected to the MSC on one side and to the BTS on the other. Function of BSC: The BSC performs the Radio Resource (RR) management for the cells under its control.
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Switching Subsystems:
Mobile Switching Center
The basic switching function is performed by the MSC
Functions of MSC The main function of the MSC is to coordinate the set up of calls between GSM mobile and
PSTN users. Specifically, it performs functions such as paging, resource allocation,
location registration, and encryption.
Home Location Register [HLR]
The HLR is a database that permanently stores data related to a given set of subscribers.
The HLR is the reference database for subscriber parameters. Various identification
numbers and addresses as well as authentication parameters, services subscribed, and
special routing information are stored.
Visitor Location Register [VLR]
The VLR is a database that contains temporary information about subscribers that is
needed by the MSC in order to service visiting subscribers.
Authentication Center [AuC] Authentication information and ciphering keys are stored in a database within the AUC,
which protects the user information against unwanted disclosure and access.
Equipment Identify Register [EIR] EIR is a database that stores the IMEI numbers for all registered ME units. There is generally one EIR per PLMN.
Operation and Maintenance Center (OMC): The OMC provides alarm-handling functions
to report and log alarms generated by the other network entities. The OMC also keeps
track of the different software versions running on different subsystem of the GSM.
GSM Interface
1. Air interface or U m interface : [ Between BTS and MS] Functions:
Universal use of any compatible mobile station in a GSM network A maximum spectral efficiency
2. A bis -interface [Between BSC and BTS]
Functions: Voice-data traffic exchange Signaling exchange between the BSC and the BTS Transporting synchronization information from the BSC to the BTS
3. A-interface [Between BSC and the MSC]
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Types of Logical Channels 1.Traffic channel 2.Broadcast channels 3.Common control channels 4.Dedicated control channels
1. Traffic channels: The traffic channels are used to send speech or data services. There are two types of traffic channels. TCH/F (Traffic Channel Full rate) The TCH/F carries information at a gross bit rate of 22.8 kbit/s (after channel coding).
The net (or effective) bit rate at the TCH/F is for speech 13 kbit/s and for data 12, 6 or 3.6 kbit/s (before channel coding).
TCH/H (Traffic Channel Half rate) The TCH/H carries information at a gross bit rate of 11.4 kbit/s. The net bit rate at the
TCH/H is for speech 5.6 kbit/s and for data is 6 or 3.6 kbit/s.
2. Broadcast Channels: The broadcast channels are point-to-multipoint channels which are only defined for the downlink direction (BTS to the mobile station).
BCCH (Broadcast Control Channel) Via the BCCH, the mobile station is informed about the system configuration
parameters (for example Local Area Identification, Cell Identity and Neighbor Cells. The BCCH is also known as beacon.
FCCH (Frequency Correction Channel)
The FCC transmits a constant frequency shift of the radio frequency carrier that can be used by the mobile station for frequency correction.
SCH (Synchronization Channel) The SCH is used to time synchronize the mobile stations. The data on this channel carries the TDMA frame number and the BSIC (Base Station Identity Code).
CBCH (Cell Broadcast Channel)
The CBCH is used for the transmission of generally accessible information (SMS) in a cell, which can be polled by the mobile station.
3. Common Control Channel
PCH (Paging Channel) The PCH is used in the downlink direction for paging the mobile stations.
AGCH (Access Grant Channel) The AGCH is also used in the downlink direction. A logical channel for a connection is
allocated via the AGCH if the mobile station has requested such a Channel via the RACH.
RACH (Random Access Channel) : The RACH is used in the uplink direction by the
mobile stations for requesting a channel for a connection.
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4. Dedicated Control Channels Dedicated control channels are full-duplex, point-to-point Channels .
SACCH (Slow Associated Control Channel) :The SACCH is a duplex Channel which is always allocated to a TCH or SDCCH. The SACCH is used for transmission of signaling data, radio link supervision measurements, transmit power control and timing advance data. FACCH (Fast Associated Control Channel) :The FACCH is used as a main signaling link
for the transmission of signaling data (for example handover commands). SDCCH (Stand-alone Dedicated Control Channel) :The SDCCH is a duplex, point-to-
point Channel which is used for signaling in higher layers. The SDCCHs are used for service requests (for example Short Message Service), location updates, subscriber authentication, ciphering initiation, equipment validation and assignment to a TCH.
Channel Combination
1.TCH/F + FACCH/F + SACCH/F 2. TCH/H + FACCH/H + SACCH/H 3. (TCH/F + FACCH/F + SACCH/F) or (TCH/H + FACCH/H + SACCH/H) 4. FCCH + SCH + CCCH + BCCH 5. FCCH + SCH + CCCH + BCCH + SDCCH/4 + SACCH/4 6. CCCH + BCCH 7. SDCCH/8 + SACCH/8
Frame Types
1. TDMA frame A TDMA frame consists of eight timeslots (physical channels). The length of a timeslot is 0.577 ms. The length of a TDMA frame is therefore 4.62 ms. 2. 26-TDMA multiframe This multiframe is defined as a succession of 26 TDMA frames, and corresponds to the 26 x 8 BP or 120 ms cycle used in the definition of the TCH/F and TCH/H. 3. 51-TDMA multiframe
This multiframe is defined as a succession of 51 TDMA frames, and corresponds to the 51 x 8 BP cycle
4. Superframe The superframe is a succession of 51 x 26 TDMA frames (6.12 sec),
5. Hyperframe It is 2048 x 51 x 26 x 8 BP long, or 3 hours, 28 minutes, 53 seconds and 760
milliseconds.
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Chapter 3 - GPRS & EDGE
General Packet Radio Service (GPRS) General Packet Radio Service (GPRS) is a mobile data service available to users of GSM
mobile phones. It is often described as "2.5G", that is, a technology between the second (2G)
and third (3G) generations of mobile telephony.
GPRS is packet-switched which means that multiple users share the same transmission
channel, only transmitting when they have data to send.
Key User Features of GPRS Speed
Rich Media Applications
Internet on the mobile
Always on
GPRS Advantages For Operators More Revenue
Huge Potential Market for Data Services
Fast Roll-out and Continuous Network Expansion
GPRS uses excess voice capacity for data
Typical GPRS Services Value added services - Information services, games, e-commerce. Location-based applications - Navigation, traffic conditions, airline/rail schedule Vertical applications - Freight delivery, fleet management, sales-force automation. Location sensitive Advertising - A user nearing a cinema hall or a restaurant receives
flashes of advertisement
GPRS System Architecture These elements are:
Packet Control Unit (PCU)
Serving GPRS Support Node (SGSN): the MSC of the GPRS network
Gateway GPRS Support Node (GGSN): gateway to external networks
Border Gateway (BG): a gateway to other PLMN
Intra-PLMN backbone: an IP based network inter-connecting all the GPRS
elements
Charging Gateway (CG)
Legal Interception Gateway (LIG)
Domain Name System (DNS)
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GPRS architecture Packet Control Unit (PCU) :The PCU separates the circuit switched and packet switched
traffic from the user and sends them to the GSM and GPRS networks respectively. It also performs most of the radio resource management functions of the GPRS network
Channel Codec Unit (CCU) :The CCU is realized in the BTS to perform the Channel Coding (including the coding scheme algorithms), power control and timing advance procedures.
Serving GPRS Support Node (SGSN) : The SGSN of the GPRS network is equivalent to the MSC of the GSM network.
SGSN functions Authentication, Authorization
GTP tunneling to GGSN
Mobility Management
Session Management
Interaction with HLR, MSC/VLR
Charging & statistics
NMS interfaces Gateway GPRS Support Node (GGSN) :The GGSN is the gateway to external networks. GGSN functions Interface to external data networks
Encapsulate in GTP and forwards end user data to right SGSN
Routes mobile originated packets to right destination
Filters end user traffic
Collects charging and statistic information for data network usage
Domain Name Servers :These devices convert IP host names into IP addresses.
Firewalls :A firewall protects an IP network against external attack (for example, hackers from the mobile users or from the Internet).. The firewall can also include NAT (Network Address Translation).
Border Gateway :The Border Gateway (BG) is a router that can provide a direct GPRS tunnel between different operators' GPRS networks. This is referred to as an inter-PLMN data network.
Charging Gateway :GPRS users have to be charged for the use of the network. In a GSM
network, charging is based on the destination, duration, and time of call.
MS Class Type A :GPRS and Speech at the same time
Type B :GPRS and Speech (not at same time) (Automatically switches between GPRS
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and speech modes)
Type C :GPRS only (or manually switched between GPRS and speech modes)
EDGE
EDGE, or the Enhanced Data Rate for Global Evolution is the new name for GSM 384. The
technology was named GSM 384 because of the fact that it provided Data Transmission at a
rate of 384 Kbps.
One Symbol for every 3 bits. Thus, EDGE Rate = 3x GPRS Rate.
EDGE benefits Short-term benefits:
Capacity and performance Easy implementation on a GSM/GPRS network
Cost effective
Increase the capacity and triples the data rate of GPRS
Enabling new multimedia services
Long-term benefit: Harmonization with WCDMA
EDGE Applications
Streaming Applications
Very high speed downloads
Corporate Intranet connections
Quicker MMS
Video Phone
Vertical corporate applications Video Conference, Remote presentations.
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Chapter 4 - GSM 3G
Wireless Generations
1 G - First Generation - Analog - Only mobile voice services - AMPS, NMT-450, TACS etc.
2 G - Second Generation - Digital - GSM, CDMA(IS-95), DAMPS(IS-136), ETDMA, PDC etc
3 G - Third Generation Digital- W-CDMA
4 G Fourth Generation - Digital- LTE ,LTE-A
Limitations of 2G Systems
Multiple Standards - No Global Standards
No Common Frequency Band
Low Data Bit Rates
Low Voice Quality
No Support of Video
Various Network Systems to meet Specific Requirements
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3rd Generation (3G) Communication 3G networks use IP connectivity, which is packet based.
Specifically, 3G wireless networks support the following maximum data transfer rates: 2 Mbits/second to stationary devices.
384 Kbits/ second for slowly moving devices, handset carried by a walking user.
128 Kbits/second for fast moving devices, such as handset in moving vehicles.
Characteristics of 3G services Always-on connectivity.
Multi-media service with streaming audio and video.
Email with full-fledged attachments such as Power Point files.
Instant messaging with video/audio clips. Fast downloads of large files such as faxes and Power Point files.
Access to corporate applications.
Advantages Of 3G New radio spectrum to relieve overcrowding in existing systems.
More bandwidth, security and reliability.
Interoperability between service providers.
Fixed and variable data rates.
Backward compatibility of devices with existing networks.
Always-online devices, 3G will use IP connectivity. Rich multimedia services.
Spectrum Allocation For IMT-2000
The following spectrum allocations are made for IMT-2000 by ITU till today:
1885-2025 MHz and 2110-2200 MHz (Core band for IMT-2000)
1710-1885 MHz and 2500-2690 MHz (Additional band).
806-960 MHz (Additional band)
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Technologies For IMT-2000
3G Network Architecture The 3G network basically comprises of following three elements: 1. Core Network
2. Access Network
3. Terminal or User Equipment. 1.Core Network (CN)- The basic function of core network Switching and routing
Call Control
Mobility Management (MM)
Managing the Subscriber Information
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Main Nodes in Core Network MSC-Server(MSC-S)
Media Gateway (MGW)
SGSN
GGSN
HLR
EIR
AUC 2. Access Network (AN)- Access network in 3G system is called RAN (Radio Access Network). Node-B (Equivalent to 2G BTS) , RNC (Equivalent to 2G BSC) are the main nodes of RAN. 3.User Equipment (UE) It is the combination of User equipment and USIM. User equipment
may be laptop or mobile phone and SIM of 3G Systems is referred as USIM.
Migration path
For GSM : GSM GPRS EDGE W-CDMA.
For CDMA :One cdma2000 (MC-CDMA)
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Chapter 5 - RF Planning & Drive Test
Objectives Of Radio Frequency Engineering Adequate coverage :Contiguous coverage of the required areas without appreciable
holes Adequate depth of coverage (i.e. outdoor or indoor, 1 W or 8 W mobiles) to meet the companies marketing plans.
Traffic handling capacity :Accommodating traffic in the busiest hour with only a
low probability of blocking Quality of Service (QOS) :Adequate service quality across the required areas (i.e.call
drop, congestion, setup success rate, voice quality levels) to meet the companies marketing plans.
Network growth accommodation: Extension of coverage to new areas -Expanding
the network capacity so that the quality of service is maintained at all times. Cost effective design: Lowest possible cost over the life of the network while meeting
the quality targets.
Constraints of Radio Planning
The license requirements
GSM system specific parameters (e.g. GSM Rec. 05.05)
Manufacturer-specific features and parameters
Radio communication principles and fundamentals
Budgetary factors
RF planning: Three main goals Coverage Quality in the uplink and downlink direction Capacity requirements.
Site Configuration
3sector sites for (sub)urban areas
2sector sites for road coverage
Omni sites for rural areas.
Radio planning methodology
Define design rules and parameters Set performance targets Design nominal plan Implement cell plan Produce frequency plan Optimize the network Expand the network.
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Drive Test Tool (TEMS Products)
TEMS offers solutions for planning, development, optimizing, troubleshooting and
expanding mobile networks. TEMS Optimization Solutions provides every tool needed in
order to maximize the Quality of Service and get the most out of the network investment.
TEMS Cell planner Universal
TEMS Cell Planner Universal is Ericssons tool for mobile radio network planning.
TEMS Cell Planner Universal helps the user to roll out and expand mobile radio networks,
and optimize radio network regarding service availability and service quality. It assists the
user in a number of complex tasks, including network dimensioning, traffic planning,
site configuration, and frequency planning.
TEMS CellPlanner Universal provides support for WCDMA, GSM 850, GSM 900, GSM 1800,
GSM 1900, iDEN, CDMA, CDMA2000 1xRTT, TDMA/AMPS, NMT 450, NMT 900, TACS, and
E-TACS. TEMS CellPlanner Universal also provides support for GPRS and EGPRS (EDGE),
implemented in GSM system
TEMS Investigation
TEMS Investigation is an air interface test tool for real-time diagnostics. It lets you
monitor voice channels as well as data transfer over GPRS, circuit-switched (CSD) or
high-speed circuit- switched (HSCSD) connections. It also measures radio parameters,
assesses speech quality, and decodes air interface messages efficiently and easily.
Process of Radio Network planning Collection of the input parameters like requirement of capacity, coverage and quality Pre planning is done (which involves calculation of no. of BTSs with the objective to
obtain maximum coverage at minimum cost.) Site survey involves selection of candidate sites based on feasibility study of
constructing by Civil engineers Frequency allocation is done on the basis of Cell to Cell channel to interference ratio(C/I) Parameter planning is done which involves channel configurations, power control and
network specific parameters The final radio network plan involves rest of the parameters like power budget
calculations and considering path loss calculations.
Optimization involves monitoring, verifying and improving the performance of the radio network.
Traffic in the network is given in terms of erlangs. One erlang ( Erl) is defined as the amount of traffic generated by the user when he or she uses one traffic channel for one hour.
Commonly used Erlang tables are Erlang B and Erlang C.
Erlang B assumes that if calls cannot go through then they get dropped (i.e. no queuing possible).
Erlang C considers that if a call does not get through then it will wait in a queue.
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Propagation models Okamura-Hata model( for Macro Cell) Walfishikegami model( for Micro Cell).
Radio resource management (RRM):The management of radio resources, functions related to mobile location update, communication management issues such as handover and roaming procedure handling,come under radio resource management (RRM).
Procedure of Drive Test When the drive testing starts, two mobiles are used to generate calls with a gap of few
seconds (usually 15-20 s). The third mobile is usually used for testing the coverage. It makes one continuous call,
and if this call drops it will attempt another call. The purpose of this testing to collect enough samples at a reasonable speed and in a
reasonable time. If there are lots of dropped calls, the problem is analysed to find a solution for it and to
propose changes.
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Chapter 6 - MVAS
M-VAS (Mobile Value Added Services) is a well established and rapidly growing set of mobile applications beyond basic voice and messaging services.
Characteristics of M-VAS
Standalone in terms of profitability Stimulates incremental demand for core or basic services Do not cannibalize core or basic service May be sold at premium price Provides operational synergy with core or basic services
Types of M-VAS
Independent or standalone:This is not required to be coupled with a basic service. Example- Mobile Advertising is not dependent on voice calls.
Dependent or non-standalone: This is required to be coupled with a basic service.
Example- In Voice Mail service, re-direction of call is dependent on basic services. Necessity of M-VAS To maximize revenue To increase ARPU (Average Revenue Per User) To survive in competitive environment To satisfy the growing demand of customers To improve loyalty To continue expansion
Effect of M-VAS M-VAS is very much effective for:
Mobile Telecom Service Providers Value Added Service Providers Content aggregators
BSNL M-VAS Solution
BSNL implements M-VAS through SDP (Service Delivery Platform) SDP addresses the needs of both Operators and Content Providers BSNL SDP manages and delivers contents like- Music, Mobile TV, Videos,Games etc. BSNL SDP is capable to supports different formats requested by different Terminals
Availing of BSNL M-VAS STK (SIM Tool Kit) USSD (Unstructured Service Supplementary Data BSNL Live
M-VAS display through Cellone My Portal News Finance Entertainment
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TV schedule Travel Downloads Astrology Cricket
M-VAS Pricing
USSD Features
Session oriented A menu based service Flexible to design dynamic menus Accessible directly from phone screen Extremely user friendly Almost seven times faster than conventional SMS A message of a maximum of 182 characters USSD has a dialogue concept but no store & forward
USSD Benefits
No clogging inbox since there is no storing mechanism Faster Non intrusive alerts can be received without filling SMS box
BSNL Live BSNL Live is a WAP (Wireless Application Part) Portal which offers one stop shop for all Information, Entertainment and Communication related requirements. It is a gateway for M-VAS.
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Through BSNL Live one can access: Movies Videos Music Games
Streaming vs. Downloading Streaming content is sent in compressed form over Internet in a continuous stream and displayed on the compatible Mobile Set of the user in real time without getting stored in the memory of the Mobile set. Usually, Movies are streamed. Downloading allows to store the content into the memory of the compatible Mobile Set and it can viewed as many times as the user wants. Contents like Video clips, full track songs etc can be downloaded. Charges for BSNL Live Services Two types of charges are applicable: 1. Surfing/downloading charges as per plan chosen by the customer. 2. Whenever customer wants to buy any content , he will have to pay the price of the content. The price would be displayed before downloading/streaming. Handset configuration for 3G Services 1. APN settings through SMS 2. APN settings through Internet 3. mimobi.tv application settings APN settings through SMS APN stands for Access Point Name. Presently four APNs are being used by BSNL: bsnlnet bsnllive bsnlstream bsnlmms
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Chapter 7 - MIN (Mobile Identification Number)
The mobile identification number (MIN) or mobile subscription identification number (MSIN) refers to the 10-digit unique number that a wireless carrier uses to identify a mobile phone, which is the last part of the international mobile subscriber identity (IMSI).
In CDMA mode, the MS is identified using either MIN or IMSI. The MIN is a 10-digit (34-bit) number and consists of two parts
MIN1 corresponds to the least significant seven digits (24-bits) of MIN. MIN2 corresponds to the most significant three digits (10-bits) of MIN
Unlike the IMEI, the MIN is not an attribute of the physical phone. The MIN is stored in a
database that the cellular provider manages and can be changed at any time.
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Chapter 8 - Roaming & International Roaming
There are two operating modes for PLMN (Public Land Mobile Network) selection available in the MS, automatic and manual.
In both automatic and manual modes, the concept of registration on a PLMN is used.
An MS (Mobile Station) successfully registers on a PLMN if:
The MS has found a suitable cell of the PLMN to camp on; and a LU (Location Update)
request from the MS has been accepted in the LA (Location Area) of the cell on which the MS is camped.
When the PLMN has been successfully registered in the MS, the PLMN identity is stored on the SIM card.
National roaming is allowed and activated on a LA [location Area] basis. Agreement should be Bilateral so as to have both In & Out Roaming. BSNL has CMTS (Cellular Mobile Telephone Service ) Licences for 21 Service Areas out of
total 23 Service Area. i.e. whole of India except Delhi and Mumbai
BSNL has installed a solution provided by M/s Roamware, USA. This basically enables to have one nodal network in BSNL and all the remaining networks can piggy back on the nodal network.
W.B Circle is the nodal circle in BSNL and all other BSNL networks piggy back on W.B.Circle
for International Roaming.
IMSI format - Digits- MCC-MNC-Subs./MSC identity No. of Digits - 3 2 - 10 digits ( Total 15)
Dual IMSI has 2 IMSIs. IMSI of subscriber pertaining to his home network and dummy
IMSI Sponsor Network.
With W.B.Circle as nodal circle, the SIM card for Roaming abroad would require W.B.Circle like IMSI. This would require TRIPLE IMSI SIM Cards. i.e. a SIM card with Home IMSI, sponser Spice like IMSI( Not used now ) and W.B.Circle like IMSI. BSNL now introduce Triple IMSI SIM cards for International Out Roaming
Presently Subscribers of foreign Operators not Permitted to Roam in Assam, J&K and N.E.
However, Post paid Subscribers of these Service areas can Out Roam in foreign operators network.
Financial Settlements with Foreign Operators is done by West Bengal Circle for whole of
BSNL. West Bengal Circle is responsible for Reconciliation and Financial settlements.
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International Roaming agreement documents AA 12 This is the basic legal framework document for bilateral international roaming
relationships, inter-alia, defining law with which the agreement would be governed, period of validity, liabilities of parties, definitions etc. AA-13 - This is operational document containing practical principles and procedures,
the parties agree to implement on international roaming. It inter-alia, contains billing & accounting procedures, settlement procedures, testing and fraud prevention procedures
AA - 14 - This document basically contains the list of services being offered by BSNL to
In-roamers, tariffs and taxes imposed by BSNL on In-roamers, Bank A/c details of BSNL, contact details of various officers in BSNL with regard to international roaming.
IR-21 - The IR-21 document gives technical details of the BSNL Network i. e. the
Network Codes, MSRN Series, IMSI Series, GT Addresses, etc. Procedure for selecting International Roaming option in the SIM card
Insert the BSNL International Roaming SIM card in the mobile handset. Switch on the handset. Go to Cellone menu and select it. Then go to Network menu under Cell one menu and select it. Finally select International Option out of the two options available,namely National and
International. Roaming Terminology Bilateral : Foreign as well as BSNL subscribers can roam in each others network. In Roamers : Only foriegn subscribers can roam in BSNL network in India and not vice
versa. Out Roamers : Only BSNL subscribers can roam in Foreign network and not vice versa.
BSNL is providing International Roaming services in 476 Networks in 195 countries If someone encounter any difficulties while roaming abroad, one can book complaint at
www.ir.bsnl.co.in OR Call +919434024365
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Chapter 9 - Project Vijay
Objectives of Project Vijay Expand reach ensure availability of BSNL products at more than 95% of telecom
retail outlets Capture significant share (25-30%) of retailer's counter sales (increase extraction) Build distinctive channel management capabilities Nurture and build strong and viable
channel partner network
Key terms used in Project Vijay FoS [ Feet on street] : Franchise's employees who will visit retailer shops, deliver material and collect CAF (Customer Application forms ) forms
Primary Sales:Sales of product from BSNL to franchise
Secondary Sales:Any sales from franchise unit to retailer
Tertiary sales:Product sales from retailer to end-customer.
Reach:Reach defined as the ratio of telecom retail outlets (multi-brand telecom outlets) that sell BSNL products to the total number of telecom retail outlets in a particular geographical area.
Extraction:Extraction defined as the share of BSNL sales in the total sales of a particular multibrand telecom outlet
MBO: multi-brand telecom outlets
Revised structure of Franchisee channel Primary sales will be made from BSNL SSA to Franchisee. Franchisee will make the sales to Sub Franchisee and also to MBO retail Outlets through FoS. Sub Franchisee will also make sales to MBO retail Outlets in its area. MBO retail Outlets will make the sales to customers.
Categories of retailers
The category of retailers are different according to the characteristics which depends on number of SIMs sold per month or amount of Recharge sales per month.
Class A:The Retailers who sold more than 100 SIMs per month or Recharge sales more than Rs. 3 lakhs per month come under this category. For examples large multi-brand telecom outlets comes under this category.
Class B:The Retailers who sold between 50-100 SIMs per month or Recharge sales between Rs.1- 3 lakhs per month come under this category. For examples large kirana shops, medium multi-brand telecom outlets, STD/ PCO shops, etc. comes under this category.
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Class C:The Retailers who sold less than 50 SIMs per month or Recharge sales Between Rs. 0.5-1 lakh per month come under this category. For examples medium kirana stores, small
multi-brand telecom outlets, etc. comes under this category.
Class D:The Retailers who sold negligible (mostly nil; may sell 10-30 SIMs per month) or Recharge sales less than Rs. 50,000 per month come under this category. For examples small kirana stores, paan shop, tea stall, etc. comes under this category.
Franchisee Structure
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Franchisee Team Members
Franchisee Manager is expected to manage up-to 2 Franchisees and visit them every alternate day; Franchisee Manager is also expected to visit each sub franchise once a month.
Retailer Manager Coordinators expected to manage up to 15 Retailer Managers and does 1
inspection visit per Retailer Manager per month. Each retailer manager is typically assigned 200-300 retailers, depending on area geography
and is expected to visit each retailer 2 times a month.
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Awards:
In case of a tie, the award amount may be equally split.
In order to qualify for an award, the Franchisee Manager or Retailer Manager coordinator must meet a minimum of 10% achievement on Primary sale (# of SIM and Recharge value), Similarly in, order to qualify for the award, the Retailer Manager must meet a minimum of 30% achievement on no. of retailers visits done as a proportion of the total no of retailer visits assigned.
The final decision on awards at the circle levels should be made by the PGM/GM (Consumer Mobility) at circle level at the end of the month, after taking in to the account the average score on KPAs received from SSAs
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Chapter 10 - Sancharsoft
Sancharsoft :Sancharsoft is a SIM Inventory Management Application is jointly designed and maintained by IT Cell Chennai Telephones and ITPC Hyderabad. SIM Inventory Management is a web based application for integrated management of O&M and Sales & Distribution Channels
Application is hosted on Zonal WEB server with oracles 8i server at back end
Sancharsoft Features Procurement, allotment, distribution and sale through online transactions.
Enabling/Activation of SIM based on sale, CAF data
CAF monitoring can provided alert to Franchisee, Retailers and customer through SMS
Reconciliation of Sold inventory v/s stock by Scheduled Synchronization/querying of IN and HLR
Integration of Franchise and commission calculation based on SIM activation info as per guidelines.
Access to Franchisee for monitoring retailers Sales if SIM card activation of SIM commission, Invoices, CAF submission status
Sales Modules, Invoice Cancellation & discount Module: -Sales modules supports sale
of SIMs, recharge vouchers, FLPP etc to customer, Franchises, DSA, PCO and other channels like circle DSA or Business associate or EPIN vendor etc.
Plan and product addition Module: - By this module new plan and products can be added.
Prepaid SIM Module: 1. Inventory Loading: - Prepaid SIM cards have to be loaded into the system.
2. CAF Data Entry and Activation: - SIM allotted to CSC, DSA and PCO etc (other than franchisee) can be activated through CSC user login 1. CAF Submission: Franchisee can generate CAF list to be submitted to SSA and also CSC
can generate similar list to submit to central storage in case of Bigger Cities/SSAs.
2. CAF data to Billing and Call Center: System will capture CAF data before activation it can be updated in billing system at the end of the day.
3. Reports At CSC/Franchisee: Daily Sales List. At SSA/Circle Level: Activation Report, Franchisee Purchase, Analysis of SIM sales up to last minute sales etc.
Postpaid SIM Module: Postpaid SIM inventory consists of dummy SIM cards and MSISDN number.
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Product Conversion Module: This tool is for reclassification of inventory in the event of any plan is withdrawn or expires
Fixed line products (FLPP/CALL Now/Sancharnet/ITC) Module: These products can be sold through Sancharsoft thus consolidating all prepaid products under single inventory package.
Management Login Module: This module is used by senior officers of BSNL to monitor the sales activities.. Following reports are available to head of the SSA and Sales team.
Activation Reports: Total SIMs activated using SMS facility, Data entered into
the system, CAF submitted etc.
Franchisee Reports: List of Franchisee in any SSA, total purchase by franchisee, unsold stock with all sales outlets.
DSA/STD-PCO Reports: Available List of DSA/STD-PCO.
Retailer Sales Report: List of retailer in any SSA, Sales information from all SSAs, Detailed sales report of any Franchisee.
Sales Report: All types of products like SIM, Recharge, FLPP, CTOP etc.
Sysadmin Login Module: This module is used for the following functions: Add/Edit/View of the following activities
Circle
All India Packages (Plans)
Regional Packages
Service Packages
Workflow in Sancharsoft 1.Creation Order 2.Purchase Order 3.Deliver of Inventory 4. Enable/Pairing (Auth) Order 5. Allotment from MKTG 6. Allotment to SSA
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Chapter 11 - Overview of CDMA 2000 1X & EVDO
CDMA 2000 is a family of 3G mobile technology standards, which use CDMA channel access, to send voice, data, and signaling data between mobile phones and cell sites.
CDMA 2000 1X (IS-2000), also known as 1x and 1xRTT, is the core CDMA2000 wireless
air interface standard. The designation "1x", means 1 times Radio Transmission Technology, indicates the same radio frequency (RF) bandwidth as IS-95 i.e a duplex pair of 1.25 MHz radio channels.
CDMA Architecture The CDMA cellular mobile communication system consists of four independent subsystems 1.Mobile Station (MS) 2.Base Transceiver Subsystem (BSS) 3. Mobile Switching Subsystem (MSS) 4. Operation & Maintenance Subsystem (OMM) The above CDMA subsystems are same to that of GSM subsystems .We will not discuss them in detail here. Students can refer Chapter 2 GSM -2 G for the same
Fig: CMDA Architecture
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CDMA Interfaces
Air or Um interface [Between MS and BTS] Function: grants compatibility to MSs from different suppliers and networks of different operators enables MSs to roam ensures the frequency efficiency of the cellular system, adopts a series of anti-interference technologies and interference preventing measures.
A interface [between BSC and MSC] It transfers information for MS management, BTS management, mobility management and
connection management. Abis Interface [Between BSC and BTS] provides signaling control information for BTS configuration, monitoring,and testing and
service control.
B interface [Between VLR and MSC] B interface is used by the MSC to request the current location information of the MS
from VLR or notify the VLR to update the location information of the MS.
C interface [Between HLR and MSC] C interface transfers information for route selection and management. Once a call is
required to a MS, the Gateway MSC (GMSC) will request the roaming number of the called MS from the HLR of the called side.
D interface [Between HLR and VLR] D interface exchanges information related with MS location and user management. It
ensures that the MS can establish and receives calls within the entire service area.
E interface E interface can be used to exchange related handoff information to activate and
complete handoff and thus to complete the cross-cell channel handoff process without interrupting the communication.
N interface N interface is used to transfer route information related with the called subscriber
between MC and HLR.
Q interface [Between MS and MSC] Q interface is used for transferring short messages.
CDMA Channels
Forward channels : communication from base station to mobile station
Forward pilot channel (F_PICH): The base station uses this channel to transmit the pilot
signals that identify it and guide the mobile stations to access the network.
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Forward sync channel (F-SYNCH): The base station sends the system time and frame synchronization information to the mobile stations via this channel to keep timing and synchronize with the system.
Forward paging channel (F-PCH):The base station transmits paging, command, and traffic channel allocation information to the mobile stations via this channel.
Forward quick paging channel (F-QPCH):It is used by the base station to quickly instruct the mobile station from which time slot to receive the control message on F-PCH or F-CCCH.
Forward broadcast control channel (F-BCCH):It is used by the base station to deliver system messages to the mobile station.
Forward common power control channel (F-CPCCH):When the mobile station sends data in R-CCCH, the base station transmits reverse power control bit to the mobile station via this channel.
Forward common control channel (F-CCCH):It is used by the base station and the
mobile station to exchange control messages and short impulsive data when the mobile station has not set up a traffic channel yet.
Forward dedicated control channel (F-DCCH):When the mobile station is in traffic
channel state, it is used by the base station to transmit messages or low-rate packet and circuit data services to the mobile station.
Forward fundamental traffic channel (F-FCH):This channel is used to carry signaling,
voice, low-rate packet service, circuit data services or auxiliary service when the mobile station enters traffic channel state.
Forward supplemental channel (F-SCH):This channel is used to carry high-rate packet data service on the forward link when the mobile station enters traffic channel state.
Forward power control sub-channel (F-PCSCH): It is used for reverse power control.
Reverse Channels : communication from mobile station to base station. All Reverse channels are similar to forward channels in function only difference is that they provide communication from mobile station to base station
EVDO
EV-DO in CDMA2000 1x EV-DO is an acronym for Evolution Data Optimized or Evolution Data Only.
At the same narrowband CDMA frequency bandwidth, 1x EV-DO provides the highest data
transmission up to 3.1 Mb/s.
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EVDO System Features
Forward channel features Data rates range from 38.4 Kb/s ~ 3.1 Mb/s. Forward channels transmit full power without any power control. According to the forward channel C/I measurement, AT selects the best service
sector and applies for the highest data rate that the current forward channel can support.
All users belonging to the same service sector share unique data service channel in the TDMA mode.
Reverse channel features Data rate can reach at most 307.2 Kb/s. Reverse channels follow soft handoff. Reverse channels follow Dynamic power control. Use of Rate control enables reverse link load adjustment.
In 1x EV-DO system, there is no forward link power control because forward link
power is constant
Reverse Link Power Control :Reverse link power control aims to control output power of ATs while minimizing interference, maintaining high reverse data link quality.
Reverse Link Rate Control:In 1x EV-DO standard, AT can adjust reverse rate ranging
from 9.6 Kb/s to 307.2 Kb/s.
Adaptive Modulation Coding Technology:According to forward RF link transmission quality, the AT can request nine data rates. The lowest rate is 38.4 Kb/s, and highest rate is 3.
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Chapter 12 - Wireless-Fidelity (WI-FI) & Wi-Max
Wireless-Fidelity refer to any type of 802.11 network. Initially the term "Wi-Fi" was used in place of the 2.4GHz 802.11b standard
A wireless Access Point combines router and bridging functions, it bridges network
traffic, usually from Ethernet to the airwaves, where it routes to computers with wireless adapters
Wi-Fi Network Configuration 1. Wireless Peer-To-Peer Network: This mode is also known as ADHOC mode.At its most
basic, two PCs equipped with wireless adapter cards can set up an independent network whenever they are within range of one another. This is called a peer-to-peer network
2. Client and Access Point:This is known as INFRASTUCTURE mode and is normally
employed. In this mode, one Access Point is connected to the wired network and each client would have access to server resources as well as to other clients
Access Points have a finite range, of the order of 500 feet indoor and 1000 feet
outdoors.
Wirelssss LAN Standards 802.11b :802.11b transmits at 2.4 GHz ISM band and can handle up to 11 megabits per
second. Wi-Fi reaches only about 7 Mbps of throughput due to synchronization issues, ACK overhead etc.
802.11g: data rates up to 54 Mbps in the 2.4 GHz band.
802.11 a: operates in the 5GHz band. 802.11a has a smaller range.The major advantage is it's speed: the spectrum of 802.11a is divided into 8 sub-network segments or channels of about 20 MHz each.
802.11e: support for Quality of Service.Its applications include transport of voice, audio
and video over 802.11 wireless networks, video conferencing, media stream distribution, enhanced security applications and mobile & nomadic access applications.
802.11d : receive the regulatory information required to configure itself properly to operate anywhere on earth.
Configuring Wi-Fi SSID: Generally by default it is wireless router manufacturer name. One can set it to any
name
Channel:Default -channel 6. Can use any channel between 1 and 11
WEP key: The default is to disable Wired Equipment Privacy (WEP). If you want to turn it on, you have to enter a WEP key and turn on 128-bit encryption .It should be enabled to secure the network against eavesdropping and hacking.
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Benefits of Wi-Fi Mobility: Wi-Fi systems can provide LAN users with access to real-time information
anywhere in their organization. This mobility supports productivity and service opportunities not possible with wired networks.
Installation Speed and Simplicity: Installing a Wi-Fi system can be fast and easy and
can eliminate the need to pull cable through walls and ceilings. Installation Flexibility: Wireless technology allows the network to go where wire
cannot go. Reduced Cost-of-Ownership: While the initial investment required for Wi-Fi hardware
can be higher than the cost of wired LAN hardware, overall installation expenses and life-cycle costs can be significantly lower.
Scalability: Wi-Fi systems can be configured in a variety of topologies to meet the
needs of specific applications and installations.
Limitation of Wi-Fi networks
Coverage: A single Access Point can cover, at best, a radius of only about 60 metres. For 10 square kms area roughly 650 Access Points are required, where as CDMA 2000 1xEV-DO requires just 9 sites.
Roaming: It lacks roaming between different networks hence wide spread coverage by
one service provider is not possible, which is the key to success of wireless technology. Backhaul: Backhaul directly affects data rate service provider used Cable or DSL for
backhaul. Wi-Fi real world data rates are at least half of the their theoretical peak rates due to factors such as signal strength, interference and radio overhead .Backhaul reduces the remaining throughput further.
Interference: Wi-Fi uses unlicensed spectrum, which mean no regulator recourse
against interference. Security: Wi-Fi Access Points and modems use the Wired Equivalent Privacy (WEP)
Standards, which is very susceptible to hacking and eavesdropping. WEP( Wired Equivalent Privacy) is not very secure. WPA (WIFI Protected Access) offers much better security with the help of dynamic key encryption and mutual authentication.
WiMAX
WiMAX offers broadband wireless access at data rates of several tens of Mbit/s (up to 75 Mbit/s per base station) and within a range of several tens of kilometers (up to 50 km).
However 75 Mbit/s is achievable with a 20 MHz channel. 50 km is achievable only under optimal conditions and with a reduced data rate (a few Mbit/s). Typical coverage will be around 5 km with indoor CPE (NLOS) and round 15 km with a CPE connected to an external antenna (LOS),
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WiMAX Standards
Worldwide Interoperability for Microwave Access (WiMAX) is the common name associated to the IEEE 802.16a/REVd/e standards. These standards are issued by the IEEE 802.16 subgroup that originally covered the Wireless Local Loop (WLL) technologies with radio spectrum from 10 to 66 GHz.
Features Bridge the digital divide by delivering broadband in low-density areas Connect enterprises and residential users in urban and suburban environments where
access to copper plant is difficult Make portable Internet a reality by extending public WLAN hotspots to city hot zones Further expand hotzones to metropolitan area coverage for mobile data-centric service
delivery.
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Chapter 13 - Mobile Number Portability
Mobile Number Portability is a facility which allows a mobile subscriber of a mobile operator to retain his mobile telephone number when he switches from one mobile operator to other, irrespective of the mobile technology.
India has been divided into 23 Licensed Services Areas. Presently, Mobile Number
portability is permitted only within the boundaries of Licensed Service Areas (LSA) as defined by Department of Telecommunications, Govt. of India.
Donor Operator: Donor operator is the present service provider from where subscriber
is getting services.
Recipient Operator: Recipient operator is the operator where subscriber wants to port in.
MCHA: MCHA stands for Mobile Number Portability Clearing House Administrator.
MCHA acts as an interface or mediation agent to facilitate porting process between donor operator and recipient operator.
Ported-in (imported) numbers : Number ported into BSNL network from another operators network
Ported-out numbers : BSNL mobile numbers ported out to another operator network
Porting :Porting means the process of moving mobile number from one Service Provider to another Service Provider or from one mobile technology to another of the same or any other Service Provider with in the same LSA.
Inter technology porting is also possible i.e. a CDMA customer may come into GSM network and vice-versa without changing its present mobile number.
Both pre-paid & the post-paid subscribers of 3G, GSM or CDMA networks can avail the
MNP facility.
A subscriber can port his number more than once. A new subscriber can make a portingin request only after completion of 90 days of service period with the present service provider.
After receiving clearance from donor operator, MCHA shall fix date and time of porting
such that the porting happens within 36 hrs of the clearance from the Donor Operator or on non receipt of any communication from the Donor Operator. For J & K, Assam and North East service area, date and time for porting to be fixed shall be within 10 days from the date of receipt of clearance from the donor operator
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The Customer may, within 24 hours of making a request for porting, withdraw such
request by informing the BSNL in writing
The porting process will take at least 7 days in all LSA except Assam, NE & J&K.
In MNP, only number is ported not the services. The subscriber can not be guaranteed to enjoy the existing services after the porting. The subscriber shall be treated like a new connection in the recipient operators network. The subscriber shall have to choose the services available with the recipient operator at the time of making application for porting.
The pre-paid subscriber cannot carry forward the balance amount of talk time, if any, at
the time of porting the balance amount of talk time shall lapse.
BSNL is not charging any porting fee from subscriber for mobile number portability. However, cost of SIM card shall be charged as per the plan opted by the subscriber.
The UPC once allocated to a subscriber shall be valid for a periods of 15 days from the
date of request or such time till the number is ported out, whichever is earlier, for all service areas except Jammu & Kashmir, Assam and North East licensed areas where the validity for the UPC shall be for a period of thirty days from the date of request or till such time the number is ported out, whichever is earlier, irrespective of number of request the subscriber makes.
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Chapter 14 - Earthing & Power Plant
Power plant Classification 1.Based on Capacity
Power plants Small exchange power plants
Medium exchange
power plants
Large exchange power plants
Capacity: 5/12A 25/50A > 50A Input Single Phase Single Phase Three Phase
Paralleling of rectifier
Not possible Only manual paralleling is
possible
Auto paralleling is possible
Power plant comprises 3 parts
1. Float Rectifier 2. Battery Charger 3. Switching Cubicle.
1. Float Rectifier
The function of the Float Rectifier is to receive three phases 440 V AC and to give a constant 51.5 Volts D.C without AC ripples.
The steps involved to achieve the function are
a) Step-down b) Rectification c) Filtering of A.C. ripples.
d) Regulation. Regulation is done
1. By Transductor or saturable reactor or magnetic amplifier method. 2. By varying the secondary of the main transformer automatically depending on
output voltage. 3. By SCR method. 4. SMPS method.
Four main parts of a Float Rectifier a) 3 phase step-down transformer b) Rectifying circuit c) Smoothening or Filtering circuit
d) Control circuit. 2. Battery Charger Functions of Battery charger.
To Initial charge a battery set:- For initial charging, the battery charger capacity should be at least 14% of AH capacity of battery set.
To normal charge the battery set at 10 hour rate.
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To use as Float rectifier during emergency condition by suitable links. To charge the sick cell.( provision exists in some power plants only).
3.Switching Cubicle
The Switching Cubicle essentially provides for the termination of: i. The paralleled output from the Float Rectifiers connected with the Exchange load. ii. The paralleled output from the Battery Chargers. iii. The positive and negative bus bar risers for the batteries. iv. The positive and negative bus bar risers for the exchange. v. Arrangement for manual operation of the knife switches for floating of either all
batteries or any one battery. The knife switches are so arranged and interlocked that except for the battery on charge, other batteries remain connected across the exchange during or after any switching operation.
All the knife switches are of the single pole double throw slow to break type, one each
for every battery.
Another classification of power plant is
1.Single unit type :Float Rectifier (FR),Battery charger (BC) and switching cubicle (SWC) will be in single container .Eg: 5/12A PP 2.Two unit Type :One unit is FR/BC/SWC and another unit is FR
3. Three Unit Type: FR/BC/SWC are all in individual units
Nowadays mostly 2 units p/p are used with maintenance free batteries and all transmission power plant are 2-unit type only. The latest being P/P of SMPS with VRLA batteries.
Earthing
Earth Electrode System For Telephone Exchange To provide an earth connection to the battery circuit to stabilize the battery
potential of the lines and equipment with respect to earth, thus reducing the risk of cross talk due to lines and equipments assuming an indefinite voltage with respect to earth, and enabling single pole switching to be used on the exchange power plant. To provide a direct connection with earth for lightning protective apparatus.
To provide protection to persons and plant against leakage from station power wiring to metallic apparatus, frames etc.
To provide a means of earthing electrostatic screens on apparatus and of earthing
lead sheaths of cables.
To complete the circuit of telephone systems, employing a common earth path for signaling purposes.
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Standards for resistance of earth electrode systems
The resistance of the earth electrode system should be as low as possible and in any case should not normally exceed 2 ohms at any time for the year.
The worst condition occurs in winter when specific resistively of soil increases sharply with temperature near or below 0 C, where it exceeds 2 ohms
The earth resistance of Earth electrode system for Electronic exchanges should be less than 0.5 Ohms.
Classes of Earthing Systems :Two major categories
(a) Service Earthing Systems (i) switching equipment earth (ii) transmission equipment earth (iii) measuring equipment earth (iv) A.C. power supply earth (v) Corrosion mitigation earth (vi) Miscellaneous equipment earth (e.g. telegraphs).
(b) Protective Earthing System (i) Power system earth to provide protection against excessive current; (ii) Lightning protective earth to provide protection against excessive voltage
Types of earth electrode systems
1. Spike earth electrode system The present standard for spike earth-electrode system consists of twenty 25.0 mm or 38.00 mm diameter G.I pipes, each of 275 or 375 cm length. Each pipe is used as an earth spike driven to its full length into the ground, the spacing between any two being not less than 375 cms. In practice a spacing of 375 cms is found adequate and in no case should this spacing be permitted to be less than 250 cms
2. Lead Strip Electrode System
This consists of a lead strip 1 mm wide and 6 gms/square cm buried at a depth of from 60 to 90 cms. The strip should be preferably laid in one continuous length of 2450 cms. Otherwise two lengths of 1225 cm should be laid at least 250 cm apart and overlapped by at least 152 mm, the two electrode being parallel at the M.D.F earth bar.
3. Earth plate electrode system This consists of four galvanized iron plates of 145 SWG 76 cms square.These four plates are placed vertically and at diagonally opposite in an excavation 185 cm square and of a depth sufficient to reach damp soil. The depth should never be less that about 250 cms and need not be greater than 500 cms
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Conditions determining the type of earth electrode system to be used.
a) Spike earth electrode system: This system is generally used at all new auto exchange installations where adequate space is available around the exchange building and where subsoil suitable for driving in pipes to the prescribed depth exists.
b) Lead strip electrode systems: This is used when adequate space around the
exchange building is available but where rock is encountered at a depth less than 375 cm below ground level.
c) Earth plate electrode system: This is employed when the layout of the exchange site
is such that adequate space is not available to install an earth electrode system of types (a) and (b) mentioned above.
SMPS
SMPS means Switch Mode Power Supply. This is used for D.C to D.C conversion. This works on the principle of switching regulation. The SMPS system is highly reliable, efficient, noiseless and compact because the switching is done at very high rate in the order of several KHz to MHz.
Application of SMPS:The SMPS regulators are used in B.S.N.L at various locations like CDOT, E10B Transmission systems etc. Power plants upto 2000A capacity have been developed using SMPS principle.
Specification of SMPS Power Plant 1) Input Voltage: 320 V to 480 V Frequency :45 Hz TO 65 Hz 2) Output Voltage
in Float Mode: -54.0 0.5 V. adj range -48 V to -56V in charge mode : -55.2 V 0.5V
3) Input power factor >0.95 Lag with 25% to 100% load at nominal input.
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Chapter 15 - Charging and Billing in GSM/CDMA
Billing and customer care system is an Integrated Customer Care, Billing and accounting platform which provides provisioning of wide range of GSM services like Tele-services Bearer services, supplementary services, GPRS, WAP, IN services etc. B&CCS takes care of activation, deactivation, suspension and change in the subscriber services.
Functions of B&CCS
The major functions of B&CCS include. Collection of Call Detail Record (CDR) from Mobile Switching Centers. Timely and accurately invoicing of call details. Providing different Billing cycles for different category of subscribers with a support of
differential Tariff. Support of charging for various types of existing and new services. Provisioning of services for mobile subscribers. Customers care for services requests and bill inquiry.
Connectivity Customer Care Nodes (CCN) Connectivity: For extending Provisioning & Customer Care
facility to all the Customer Care Nodes (CCN) of a Billing Zone are connected to The B&CCS through Level1 router via an E1 link. The Level Routers are connected in a Ring Network. Each E1 link from CCN sites of a Billing Zones is backed up with one ISDN BRI connectivity. Depending on their physical location, the CCN may have connectivity to the Ring Network via a Level-2 router.
MSC Connectivity Each MSC location is connected to B&CCS with E1 link & ISDN BRI backup. The E1 link is connected to the MSC router and than connected to X.25 router. All the MSC locations from MSC router are connected to a Central Router at Billing Center. The Central Router is connected to the Billing Servers where all the CDRs are sent
for BILL processing.
Components of Billing & Customer Care System 1. Mediation Device: Mediation Device in the BCCS performs three main functions
1. Collection of (Call Data Record- CDRs) 2. Mediation of CDRs 3. Distribution of CDRs.
2. Billing & Customer Care Module (B&CCM):B&CCM is a system for processing CDRs from
Mediation Device and to do customized billing
B&CCM Sub-Modules 1. Customer Services Module: It provides Man-Machine interface to handle multiple types
of services, administer customer services, process and distribute applicable exchange and field orders, etc.
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2. Order Management Module: Order entry for new or existing account, including account creation. Reply to the query from CSR on existing orders and actions performed on the order. Update the number inventory databases including MSISDN, MIN, IMSI, SIM Cards
and IMEI. Update the billing once the order is completed successfully. Interface SIM card manufacturers for the ordering and allocation of SIM cards and
update of SIM card inventory.
3. Service Provisioning Module: It provides a flow though provisioning from an order entry or billing system to the network component like Home Location Register, Voice Mail Service, Short Message Service etc. It performs the functions like creation of subscriber, Mobile Number assignment, and assignment of supplementary services
Call Detail Records (CDR) in Billing System: Whenever a call is switched in the GSM network a CDR file is generated and stored in the Switching System (MSC). Types of CDRs generated are 1. Mobile Terminated Call (48 - 52 %) 2. Mobile Originated Call (20 - 25 %) 3. Roaming (4-5 %) 4. Short Message Service (18 20 %)
SIM and Inventory Management System
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Chapter 16 - HSDPA ,LTE,LTE A
HSDPA [High-Speed Downlink Packet Access]
HSDPA is a packet based technology for W-CDMA downlink with data transmission rates of 4 to 5 times that of current generation 3G networks (UMTS) and 15 times faster than GPRS.
The latest release boosts downlink speeds from the current end-user rate of 384 kbps (up
to 2 Mbps according to standards) to a maximum value according to standards of 14.4 Mbps. Real life end-user speeds will be in the range of 2 to 3 Mbps.
HSDPA only handles the downlink while the uplink is handled by a related technology
called HSUPA. The combination of both technologies is usually called HSPA.
HSDPA Features:
Adaptive modulation and coding schemes: Quadrature Phase Shift Keying (QPSK) and 16QAM (Quadrature Amplitude Modulation).
Hybrid Automatic Repeat reQuest (HARQ) retransmission protocol. Short transmission time interval (TTI) Fast packet scheduling controlled by the Medium Access Control - high speed (MAC-hs)
protocol in Node B.
HSPDA and CDMA2000 1xEV-DV Comparison
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LTE [Long Term Evolution] Commonly marketed as 4G LTE The main goal of LTE is to provide a high data rate, low latency and packet optimized
radio access technology supporting flexible bandwidth deployments.
Advantages of LTE
High throughput: High data rates can be achieved in both downlink as well as uplink. This
causes high throughput.
Low latency: Time required to connect to the network is in range of a few hundred milliseconds and power saving states can now be entered and exited very quickly.
FDD and TDD in the same platform: Frequency Division Duplex (FDD) and Time Division Duplex (FDD), both schemes can be used on same platform.
Superior end-user experience: Optimized signaling for connection establishment and other air interface and mobility management procedures have further improved the user experience. Reduced latency (to 10 ms) for better user experience.
Seamless Connection: LTE will also support seamless connection to existing networks such as GSM, CDMA and WCDMA.
Plug and play: The user does not have to manually install drivers for the device. Instead system automatically recognizes the device, loads new drivers for the hardware if needed, and begins to work with the newly connected device.
LTE - Network Architecture
The high-level network architecture of LTE is comprised of three main components 1.The User Equipment (UE) - Mobile 2.The Evolved UMTS Terrestrial Radio Access Network (E-UTRAN).-Access Network 3.The Evolved Packet Core (EPC)- Core Network
Figure: Overview of LTE
1. The User Equipment (UE)
The mobile equipment comprised of the following important modules: Mobile Termination (MT): This handles all the communication functions. Terminal Equipment (TE): This terminates the data streams. Universal Integrated Circuit Card (UICC): This is also known as the SIM card for LT E
equipments. It runs an application known as the Universal Subscriber Identity Module
(USIM).
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2. The E-UTRAN (The access network) The E-UT RAN handles the radio communications between the mobile and the evolved packet core and just has one component, the evolved base stations, called eNodeB or eNB.
Two main functions supported by eNB The eBN sends and receives radio transmissions to all the mobiles using the analog and
digital signal processing functions of the LTE air interface.
The eNB controls the low-level operation of all its mobiles, by sending them signalling messages such as handover commands.
Figure: E-UTRAN (Access Network)
3. Evolved Packet Core (EPC) (The core network) Home Subscriber Server (HSS): component has been carried forward from UMT S and
GSM and is a central database that contains information about all the network operator's subscribers.
Packet Data Network (PDN) Gateway (P-GW) :communicates with the outside world ie.
packet data networks PDN, using SGi interface. Each packet data network is identified by an access point name (APN).
PDN gateway: has the same role as the GPRS support node (GGSN) and the serving GPRS
support node (SGSN) with UMTS and GSM. Serving gateway (S-GW): acts as a router and forwards data between the base station and
the PDN gateway. Mobility management entity (MME): controls the high-level operation of the mobile by
means of signalling messages and Home Subscriber Server (HSS).
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Policy Control and Charging Rules Function (PCRF): is a component is responsible for policy control decision-making , as well as for controlling the flow-based charging functionalities in the Policy Control Enforcement Function (PCEF), which resides in the P-GW.
Figure: Evolved Packet Core [EPC]
2G/3G Versus LTE
Following table compares various important Network Elements & Signaling protocols used in 2G/3G and LTE. The Network elements functions are same only different naming terminology is used .For eg: HLR in 2G/3G is named as HSS in LTE,VLR as MME and so on.
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LTE Parameters
LTE-Advanced (LTE-A) is an emerging and, as the name suggests, a more advanced set of standards and technologies that will be able to deliver bigger and speedier wireless-data payloads.
Peak Download Speed of LTE A : 1 Gbits/sec Peak Upload Speed of LTE A: 500 Mbits/sec
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Chapter 17 - Intelligent Network in Mobile Communication
Intelligent Network: IN is an architectural concept for the operation and provision of new services quickly, flexibly, economically and efficiently. It supports the provision, control and management of multiple telecommunication services.
Users & providers of this Service Network Provider -The company that is responsible for the telephony network
planning and maintenance Service Provider -The Company or institution that purchases IN services from the
network provider and provides it to Service subscribers. It is the organization which creates, manages and markets the service.
Service subscriber -The company, institution or individual that purchases IN services from the Service provider. One who subscribes for the service and registers with the service provider
Calling Subscriber- Calling party, the person who dials IN number
Called Subscriber- Called Party, the person who answers the IN call.
Advantages to Network Provider Additional network traffic-IN services stimulate the use of telephone network for
new applications. Hi