Sjzl20060022 ZXC10+BSSB+(V8[1].16)+Technical+Manual Fundamentals

ZXC10 BSSBCDMA2000 Base Station System

Technical Manual - Fundamentals

Version 8.16

ZTE CORPORATION ZTE Plaza, Keji Road South, Hi-Tech Industrial Park, Nanshan District, Shenzhen, P. R. China 518057 Tel: (86) 755 26771900 800-9830-9830 Fax: (86) 755 26772236 URL: http://support.zte.com.cn E-mail: [email protected]

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Revision History

Date Revision No. Serial No. Description

2006/03/20 R1.1 sjzl20060022 ZXC10 BSSB Technical Manual – Fundamentals, contents in English.

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Document Name ZXC10 BSSB (V8.16) CDMA2000 Base Station System Technical Manual -Fundamentals

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Contents

About this Technical Manual.....................................................................ix Purpose of this Technical Manual............................................................................. ix Typographical Conventions..................................................................................... ix Mouse Operation Conventions..................................................................................x Safety Signs.......................................................................................................... xi How to Get in Touch ..............................................................................................xii

Customer Support..................................................................................................................xii Documentation Support..........................................................................................................xii

Chapter 1...................................................................................13

CDMA Overview....................................................................................... 13 1G Mobile Communication System.........................................................................13 2G Mobile Communication System.........................................................................13 3G Mobile Communication System.........................................................................14

RTT Technology.....................................................................................................................15 Evolution of CDMA2000 Standards.........................................................................................16

Chapter 2...................................................................................17

CDMA Fundamentals............................................................................... 17 Spread Spectrum Communication Technology ........................................................17

Spread Spectrum Communication Theory...............................................................................17 Spreading and De-spreading..................................................................................................18 Processing Gain and Anti-Interference Tolerance.....................................................................19 Spread Spectrum Communication Features............................................................................19

CDMA System Implementation ..............................................................................21 CDMA Spread Spectrum Communication Principles.................................................................21 CDMA Spreading Code Selection ............................................................................................22

Channel Coding Technology...................................................................................24 Cyclic Redundancy Check ......................................................................................................24 Convolutional Coding.............................................................................................................24 Block Interleaving Technology................................................................................................25

Turbo Code...........................................................................................................................25

Chapter 3...................................................................................27

Key CDMA Technologies.......................................................................... 27 Uniform Frequency Reuse......................................................................................27 Power Control.......................................................................................................28

Reverse Link Power Control ...................................................................................................29 Forward Link Power Control ...................................................................................................30 Cell Breath Power Control ......................................................................................................32

Diversity Reception...............................................................................................32 Time Diversity.......................................................................................................................32 Frequency Diversity...............................................................................................................33 Space Diversity .....................................................................................................................33 RAKE Receiver ......................................................................................................................34

Soft Handoff.........................................................................................................36 Pilot Set................................................................................................................................36 Search Window.....................................................................................................................37 Handoff Parameters...............................................................................................................38

Chapter 4...................................................................................41

CDMA2000 1x.......................................................................................... 41 System Overview .................................................................................................41 Air Interface Parameters .......................................................................................42 Forward Channels.................................................................................................42 Reverse Channels.................................................................................................43 Technical Features................................................................................................44

Radio Part.............................................................................................................................44 Network Part.........................................................................................................................45

Service Flows .......................................................................................................45 Voice Service ........................................................................................................................45 Data Service .........................................................................................................................51

Chapter 5...................................................................................59

CDMA2000 1x EV-DO .............................................................................. 59 System Overview .................................................................................................59

Network Model......................................................................................................................59 System Features ...................................................................................................................60

Forward Channels.................................................................................................61 Reverse Channels.................................................................................................63

Key 1x EV-DO Technologies...................................................................................64 Reverse Link Power Control ...................................................................................................64 Reverse Link Rate Control......................................................................................................64 Forward Link TDM .................................................................................................................65 Forward Link Scheduling Strategy ..........................................................................................65 Forward Link Virtual Soft Handoff...........................................................................................65 Adaptive Modulation Coding Technology.................................................................................66 R-P Session Establishment.....................................................................................................66

Service Flow.........................................................................................................66 Session Management ............................................................................................................66 Connection Management .......................................................................................................69

1x and 1x EV-DO Comparisons..............................................................................73

Chapter 6...................................................................................75

PTT Technology....................................................................................... 75 Key PTT Technologies ...........................................................................................75

Channel Sharing....................................................................................................................75 Fast Connection ....................................................................................................................76 PTT Service...........................................................................................................................77

Abbreviations ...............................................................................89

Figures..........................................................................................93

Tables ...........................................................................................95

Index ............................................................................................97


Confidential and Proprietary Information of ZTE CORPORATION ix

About this Technical Manual

Purpose of this Technical Manual This manual provides the basic information you need for the ZXC10 BSSB system.

Typographical Conventions ZTE documents employ the following typographical conventions.

TAB L E 1 - TY P O G R AP H I C AL C O N V E N T I O N S

Typeface Meaning

Italics References to other guides and documents.

“Quotes” Links on screens.

Bold Menus, menu options, function names, input fields, radio button names, check boxes, drop-down lists, dialog box names, window names.

CAPS Keys on the keyboard and buttons on screens and company name.

Constant width Text that you type, program code, files and directory names, and function names.

[ ] Optional parameters

{ } Mandatory parameters

| Select one of the parameters that are delimited by it

Note: Provides additional information about a certain topic.

Checkpoint: Indicates that a particular step needs check before proceeding further.

Tip: Indicates a suggestion or hint to make things easier or more productive for the reader.

ZXC10 BSSB (V8.16) CDMA2000 Base Station System Technical Manual - Fundamentals

x Confidential and Proprietary Information of ZTE CORPORATION

Mouse Operation Conventions TAB L E 2 - M O U S E OP E R AT I O N C O N V E N T I O N S

Typeface Meaning

Click Refers to clicking the primary mouse button (usually the left mouse button) once.

Double-click Refers to quickly clicking the primary mouse button (usually the left mouse button) twice.

Right-click Refers to clicking the secondary mouse button (usually the right mouse button) once.

Drag Refers to pressing and holding a mouse button and moving the mouse.

About this Technical Manual

Confidential and Proprietary Information of ZTE CORPORATION xi

Safety Signs TAB L E 3 - S AF E T Y S I G N S

Safety Signs Meaning

Danger: Indicates an imminently hazardous situation, which if not avoided, will result in death or serious injury. Limit the use of this signal only to extreme situations.

Warning: Indicates a potentially hazardous situation, which if not avoided, could result in death or serious injury.

Caution: Indicates a potentially hazardous situation, which if not avoided, could result in minor or moderate injury. The signal also alerts against unsafe practices.

Erosion: Beware of erosion.

Electric shock: Risk of electric shock.

Electrostatic: The device may be sensitive to static electricity.

Microwave: Beware of strong electromagnetic field.

Laser: Beware of strong laser beam.

No flammables: No flammables can be stored.

No touching: Do not touch.

No smoking: Smoking forbidden.


xii Confidential and Proprietary Information of ZTE CORPORATION

How to Get in Touch The following sections provide information on ways to obtain support for documentation and software.

Customer Support In case of problems, questions, comments, or suggestions regarding the product, contact us by e-mail at [email protected]. You can also call our customer support center at (86) 755 26771900 and (86) 800-9830-9830.

Documentation Support ZTE welcomes your comments and suggestions on the quality and usefulness of this document. For further questions, comments, or suggestions on the documentation, you can contact us by e-mail at [email protected]; or you can fax your comments and suggestions to (86) 755 26772236. You can also explore our website at http://support.zte.com.cn, which contains various interesting subjects like documentation, knowledge base, service request and forum.

Confidential and Proprietary Information of ZTE CORPORATION13 13

C h a p t e r 1

CDMA Overview

This chapter explains: History of mobile communications.

Evolution of CDMA2000 standards.

1G Mobile Communication System Bell Labs invented the first generation (1G) cellular mobile communication system that renaming it as Advanced Mobile Phone System (AMPS) in the 1970's. North Europe including Denmark, Norway, Sweden, Finland and U.K later developed Nordic Mobile Telephone System (NMTS) and Total Access Communication System (TACS) similar to AMPS. China deployed the first analog cellular telephone communication system in 1987. Guangzhou, China deployed the first mobile office in November 1987.

Few years later, 1G analog mobile communication system limitations such as capacity deficiency, single service availability, and low voice quality led to the research and development of second-generation (2G) cellular mobile communications system.

2G Mobile Communication System Based on digital signal processing, 2G cellular mobile communication system provides higher spectrum utilization, diversified data services, better communication quality, and advanced roaming function.

A typical 2G cellular mobile communication system includes Global System for Mobile communications (GSM), IS-54/IS-136 and IS-95 and the Personal Digital Cellular (PDC) system. IS-95 is the American cellular


14 Confidential and Proprietary Information of ZTE CORPORATION

mobile communications standard set by Telecommunications Industries Association (TIA) in 1993. It adopts the CDMA technical specifications invented by Qualcomm.

Hong Kong deployed its first CDMA mobile communications system in 1995 marking the beginning of commercial CDMA applications. However, recommendations on IS-95 development by the Federal Communications Commission (FCC) of America meant IS-95 compatibility with AMPS, ensuring IS-95 bandwidth within the AMPS frequency band range. IS-95 is a narrowband CDMA system that offers limited services with several disadvantages.

In recent years, 2G voice based mobile communication services have attracted increasing number of users. Public Land Mobile Network (PLMN) users in China now exceed 100 million and are increasing at the rate of 20 million each year. The great success of 2G has led to the advanced research and development of third-generation (3G) mobile communications system.

3G Mobile Communication System International Telecommunication Union (ITU) put forth the Future Public Land Mobile Telecommunication System (FPLMTS) in 1985, a 3G mobile communications system and later renamed it to IMT-2000. The European Telecommunications Standards Institute (ETSI) released the Universal Mobile Telecommunications System (UMTS).

IMT-2000 and UMTS provide diversified services with functions and quality similar to fixed network communications systems using globally uniform frequency band and standards.

3G cellular mobile and personal communication systems provide larger system capacity and higher data transmission capability.

Current 3G system data transmission rates provide different data transmission rates in different circumstances:

144 Kb/s, while moving fast (in a vehicle)

384 Kb/s, while moving slow

3.1 Mb/s, while in static position.

3G cellular mobile communications system can provide services including video streaming, audio streaming, mobile interconnection, mobile commerce, and e-mail.

Chapter 1 - CDMA Overview

Confidential and Proprietary Information of ZTE CORPORATION 15

RTT Technology Radio Transfer Technology (RTT) is a key IMT-2000 technology. ITU collected ten terrestrial RTT interface standards from Europe, Japan, America, China, and Korea by June 1998 end.

Although ITU attempts to develop a uniform standard, two major regional standardization organizations 3rd Generation Partnership Project 1 (3GPP1) and 3rd Generation Partnership Project 2 (3GPP2) have established ITU WCDMA and CDMA2000 standards respectively. 3GPP is the 3rd generation partnership project initiated by the European Telecommunications Standards Institute (ETSI), and 3GPP2 is another 3rd generation partnership project initiated by the American National Standards Institute (ANSI). China established the Committee of Wireless Telecommunications Standard (CWTS) in April 1999, and became an official member of 3GPP and 3GPP2 in May 1999.

To define uniform IMT-2000 RTT, ITU made great efforts to integrate multiple radio access solutions excluding satellite access. ITU passed IMT-2000 Wireless Interface Technical Specifications in November 1999 and determined five RTTs for IMT-2000. These RTTs cover WCDMA of Europe and Japan, CDMA2000 of America, and the TD-SCDMA of China.

WCDMA supports following basic features:

Frequency Division Duplexing (FDD) supports multiple rates and services.

Fast power control of forward links and coherent demodulation of reverse links.

Handoff between different carriers without base station synchronization.

The base stations do not require synchronization for handoff between different carriers.

CDMA2000 evolved from IS-95 system in North America, and provides the following features:

Coherent reception of reverse links and forward link transmit diversity.

Base station synchronization using Global Positioning System (GPS).

Good compatibility with IS-95, mature technology, low risk, economical and stable.

TD-SCDMA: China first achieved Intellectual Property Right (IPR) for TD-SCDMA solution. It is based on TDMA and CDMA technologies. It adopts Time Division Duplexing (TDD), smart antenna, and software radio technologies, and is applicable to low-speed access environments.

For the ten IMT-2000 RTT technologies submitted, eight were CDMA technologies. It indicates that the CDMA technology plays a leading role in 3G mobile communications system.



Although 4th generation (4G) mobile communication network is still in its nascent stages of development, 4G mobile communication network is sure to provide higher data transmission rates than 3G system. The 4G data transmission rates can reach 10 Mb/s to 100 Mb/s.

Evolution of CDMA2000 Standards Figure 1 shows the evolution of CDMA2000 standards.

F I G U R E 1 - CDMA2000 TE C H N O L O G Y S T AN D AR D S

ZXC10 BSSB supports CDMA2000 1x RTT Release A, CDMA2000 1x EV-DO Rev. 0, CDMA2000 1x EV-DO Rev. A technology.


C h a p t e r 2

CDMA Fundamentals

This chapter explains: CDMA system fundamentals.

Key CDMA coding technologies.

Spread Spectrum Communication Technology Three primary communication transmission modes in the information era comprised spread spectrum communication, fiber communication, and satellite communication.

Spread Spectrum Communication Theory Spread spectrum communication follows the Shannon formula.

The formula for calculating channel capacity follows information theory research:

)1(log2 NSBC +×=

C is channel capacity in bits/s, B is signal bandwidth in Hz, S is signal mean power in W, and N is mean noise power in W.

According to Shannon formula, the signal bandwidth (B) and Signal to Noise Ratio (S/N) are inversely proportional if channel capacity (C) remains unchanged. Increasing signal bandwidth enables reliable information transfer at the same rate with low S/N. Even if noise drowns the signal, reliable communication occurs as long as there is significant signal bandwidth increase. Spread spectrum enables information transfer on a higher bandwidth to reduce high SNR requirement.



Spreading and De-spreading Spread spectrum communication technology is an information transmission mode that follows spread spectrum code for modulation at the transmitting end, increasing signal bandwidth required for information transfer. At the receiving end, the same spread spectrum code enables coherent demodulation to restore transmitted information.

Figure 2 illustrates the entire spreading and de-spreading processes.

F I G U R E 2 - S P R E AD I N G AN D D E -S P R E AD I N G P R O C E S S

Figure 2 illustrates modulated data conversion into narrowband signals with bandwidth B1.

Pseudo noise code (PN) generated by spread code generator spreads and modulates narrowband signals, and becomes broadband spread signals with extremely low power spectral density. As figure 2 illustrates, B2 is far greater than B1. Narrowband signals spread in broadband according to a regular pattern defined by PN and then sent out.

Signal transmission causes interference noise like narrowband noise and broadband noise.

Spread and demodulation of broadband signals at the receiving end use the same transmitting end PN and become normal narrowband signals. Bandwidth extraction of components mapped with those on the transmission side is according to regular PN pattern, and integrated with normal narrowband signals. Regular communication processing

Chapter 2 - CDMA Fundamentals


method demodulates narrowband signals into information data followed by de-spreading of interference noise into bandwidth signals.

Processing Gain and Anti-Interference Tolerance Two important spread spectrum communication system concepts types are processing gain and anti-interference tolerance.

Processing gain shows spread spectrum system SNR improvement. It reflects the system’s anti-interference performance.

Normally, the ratio of spread spectrum signal bandwidth W and

information bandwidth FΔ is the processing Gain pG.

.

FWGp Δ

=

According to theoretical analysis, anti-interference spread spectrum system performance is directly proportional to signal bandwidth before spreading than that after spreading.

However, spread spectrum system processing gain does not fully reflect system performance under interference environment. A certain SNR at the output end ensures normal system operation, despite system losses. Anti-

interference tolerance is JM , and the following defines JM :

])[( sopJ LNSGM +−=

SNR at the output end is)[( oN

S.

System loss is sL .

Spread Spectrum Communication Features Following section describes the spread spectrum communication technology features:

Strong Anti-interference Capability Spread spectrum technology enables spread and broad frequency band transfer of transmitting end signals, and the compression and restoration of receiving end spread signal bandwidth to narrowband signals. Interference signals do not relate to spread PN. After spreading the interference signals to wide band, the interference power within the same



band containing useful signals reduces. As a result, output signal/interference ratio increases, making anti-interference capability strong. Anti-interference capability is directly proportional to spread times of the band. Wider the spectrum spread, stronger is the anti-interference capability.

Multi-Access Communication Although the CDMA spread spectrum system occupies a wide band, users share the same frequency band at one time. Spectrum utilization is high. Hence, the spread spectrum system supports multi-access communication.

High Security As spread spectrum communication system spreads the transmitted information to a wide band, its power density reduces with spectrum spread. Noise may drown the signals. It is difficult to intercept or scout such signals.

Multi-path Interference Resistance In mobile communication and indoor environments, multi-path interference poses very serious constraints. The system cannot ensure smooth communication in the absence of strong anti-interference capability. Spread spectrum communication technology prevents multi-path interference through spread spectrum code correlation features. It uses multi-path energy to improve system performance.

Spread spectrum communication has several other advantages, such as accurate time and range, noise prevention, low power spectral density, and random access.

Multiple Access Technology Multi-access mode enables several user addresses use the same resource to communicate with one another. In CDMA systems, multiple access technology enables several users to share the same frequency at one time. Generally, these users are in different places and in moving state. Several satellite communication earth stations communicate through the same satellite repeater, likewise several MSs communicate at the same frequency through the base station.

Use of same transmission band causes generation of mutual interference among users. That is the so-called multi-access interference or self-interference. Signal division on the receiver incorporates certain features to avoid multi-access interference on signals from different users to differentiate them.

Mathematically, multiple access technology is the orthogonal division of signals, expressing the transmission signals as a function of time, frequency, and code.



Multiple access technology uses different features of signals to differentiate channels:

Frequency Division Multiple Access (FDMA): Different users use different frequency at one time.

Time Division Multiple Access (TDMA): Different users use different timeslots within the same frequency.

Code Division Multiple Access (CDMA): All terminals use the same band to transfer signals at one time. It implements signal splitting by using orthogonality or quasi-orthogonality between different terminal signal address code waveforms.

CDMA System Implementation CDMA is a multi-access mode with a broad development perspective. Currently, it is the development hotspot in many countries around the world.

CDMA uses a group of orthogonal or quasi-orthogonal PN sequences to enable multiple users share the frequency resources for air transmission and implement network access at the same time.

CDMA Spread Spectrum Communication Principles The spread spectrum communication system provides three implementation modes, namely, Direct Sequence Spread Spectrum (DSSS), Frequency Hopping Spread Spectrum (FHSS), and Time Hopping Spread Spectrum (THSS).

As Figure 3 illustrates, CDMA adopts DSSS technology.

F I G U R E 3 - CDMA S P R E AD S P E C T R U M C O M M U N I C AT I O N P R I N C I P L E S

3G standards use different spreading code rates. In CDMA2000 1x system, spreading code rate is 1.2288 Mb/s.



With respect to Figure 3, signal processing waveform change is as illustrated in Figure 4.

F I G U R E 4 - S I G N AL W AV E F O R M D U R I N G S P R E AD I N G AN D D E -S P R E AD I N G

+

+

Signal

Signal received

Spreading code

Spreading code

(a) Spreading

Result of spreading

Result of despreading

(b) Despreading

Spreading process adopts mod 2 calculation, which is equivalent to binary exclusive-OR calculation. A chip is the code element obtained after spreading. The term chips/s defines chip rate. Spread gain is equal to the ratio of code rate and input signal.

According to Nyquist theorem, spectrum bandwidth of pulse signals is inversely proportional to pulse bandwidth. As figure 4 illustrates, signal pulse band is wide. The pulse becomes narrower after spreading. The signal spectrum before spreading must be narrow, and signal spectrum after spreading must be wide.

Generally, CDMA can adopt several successive spread spectrum sequences to spread signals, and then perform de-spreading in reverse order to restore original data.

CDMA Spreading Code Selection Spreading code needs discrimination, and is orthogonal. Proper spreading code has the following features:

Cross-correlation: Only autologous spreading code can de-spread signals. Other spreading codes cannot de-spread signals.

Self-correlation: Autologous delay does not affect de-spreading of signals.



Easy to generate

Randomness

Providing the period as long as possible to prevent interference.

Spreading codes used in CDMA system currently include Walsh code and Pseudo-random Number (PN).

Walsh Code As an orthogonal spreading code, the Walsh code generation is according to the Walsh function set. The Walsh function is a binary orthogonal function system, with a value range of 1 and –1. It has multiple definitions. The most common one is the Handmard numbering method. The Walsh function in IS-95 adopts this definition method.

The Walsh function set is a complete non-sine orthogonal function set, used as address codes of users.

PN As there are limited Walsh codes, and the Walsh codes cannot provide random signals, PN provides a large number of spreading codes when needed. PN has similar features to noise sequence. It is a periodic binary sequence, which seems random but in fact very regular. The most common PN is the m sequence.

Orthogonality of the m sequence is not as good as that of the Walsh code. It is the cross-correlation of the m sequences of the same series. Cross-correlation of the m sequence is greater than 0 resulting in use of Walsh codes instead of the m sequence.

The m sequence features strong self-correlation. When series is high, the m sequences of different phases are orthogonal.

The period of m sequence is 2r-1. Here, r stands for the shift register series. The m sequence quantity relates to the series.

When r is 15, the m sequence is short PN.

When r is 42, the m sequence is long PN.

CDMA systems use two kinds of m sequences:

Short PN, with length of 215-1.

Long PN, with length of 242-1.

The following section compares the three CDMA system codes.

Short PN: Is used in forward and reverse channel orthogonal modulation. In forward channels, the short PNs identify different base stations. The short PN is 215-1 in length.

Long PN: Is obtained by mode 2 addition of a pseudo number generated by a 42-bit shift register and a 42-bit long PN mask. Different channels have different long PN mask. Generated by a 42-bit shift register, the long PN mask is 242-1 in length. In CDMA systems, long PN is used in forward channel scrambling and reverse link spread spectrum.



Walsh code: Due to its orthogonality, Walsh code is used for forward spread spectrum in CDMA systems.

Voice Coding Technology CDMA system uses the most effective voice coding technology called Qualcomm Code Excited Linear Predictive coding (QCELP).

QCELP voice coding standard development started in North America for 2G digital mobile phones. Qualcomm owns the QCELP voice coding algorithm patent in the US. This algorithm is applicable to both fixed rates 4 Kb/s, 4.8 Kb/s, 8 Kb/s, and 9.6 Kb/s, and variable rates ranging from 800 Kb/s to 9600 Kb/s. Voice coding technology lowers mean data rate, and increases the CDMA system capacity by two times approximately.

Channel Coding Technology Mobile communication systems have high channel coding requirements to achieve low bit error ratio (BER). Key technology used is error control coding, also called error-correction coding. Error-correction coding methods include cyclic redundancy check (CRC), convolutional coding, block interleaving, Turbo code, and scrambling. Different systems adopt different error control coding methods. CDMA2000 adopts CRC, convolutional coding, block interleaving, Turbo code, and scrambling.

Cyclic Redundancy Check CRC uses cyclic code to check and correct both single random error and burst errors. In hardware, the cyclic code implementation uses shift register with feedback. Due to its clear algebraic structure, excellent performance, and simple coding and decoding, cyclic code has become the most common anti-interference method used in data communication systems. In actual applications, CRC detects errors.

Convolutional Coding Convolutional coding technology effectively overcomes single data error generated. In 1995, Elias first put forth the convolutional code concept. Coding expressed in convolutional calculation form is convolutional code.

Convolutional coding is a form of memory coding. It is a system with memory. For an arbitrary time n outputs coded relate to both k inputs in that duration and m inputs stored in the coder.

Encoding constraint length l = m + 1. Here m refers to the number of register bytes in the encoder also called memory length.

Selecting a long encoding constraint length and coding rate for convolutional code helps achieve good performance. However, increasing



encoding constraint length increases decoding complexity accordingly. A modern super-large integrated circuit can implement convolutional coding with encoding constraint length of 9. Coding rate depends on coherent time and channel interleaving length.

Block Interleaving Technology Block interleaving technology aims to correct burst data errors in series with the number of errors in each byte de-interleaved at the receiving end fewer than the number of errors that error-correcting code can correct.

In a parameter-variable channel of land mobile telecommunication, bit errors usually occur in series because a lasting deep attenuation valley point may affect a cluster of bits. However, channel coding is valid only on detecting and correcting finite errors and short error strings.

A method to separate successive bytes in a message enables sending successive bytes in a message separately. Even though a string of errors occurs during transmission, only one or several errors appear after restoring the message with a successive byte string through de-interleaving.

After de-interleaving, error correction decoding corrects received bytes that contain random errors and restores the original message.

Radio channels may experience burst errors. As interleaving technology randomizes these burst errors, convolutional coding effectively prevents random errors. The interleave plan can be block interleaving or convolutional interleaving. Cellular system always adopts block interleaving.

Performance improvement due to interleaving depends on the diversity level and mean fading interval of channels. Delay requirements of services determine interleaving length. Voice service delay is shorter than that of data service. It is necessary to match the interleaving length with different services.

Turbo Code Implementation of Turbo code coding uses comparatively simple recursive system convolutional (RSC) code and interleaver. Its decoding is implemented through iteration and de-interleaving. Turbo code achieves error correction performance close to the theoretical limit. It features high anti-fading and anti-interference capability. Turbo code is one of the core systems of 3G mobile communication system.

As Turbo code decoding is very complicated, and decoding delay is very long, Turbo code is applicable to data services that do not require short delay. For voice services and data services that require short time delay, convolutional code works best.





C h a p t e r 3

Key CDMA Technologies

This chapter explains: Key CDMA technologies.

Uniform frequency reuse.

Power control.

Diversity reception.

Soft handoff.

Uniform Frequency Reuse Figure 5 illustrates traditional frequency reuse in FDMA and TDMA modes.

F I G U R E 5 - FR E Q U E N C Y R E U S E I N FDMA AN D TDMA

f1

f3

f4

f2

f5

f6

f7

f1

f3

f4

f2

f5

f6

f7

As figure 5 illustrates, traditional way is to divide the band allocated by radio management department into seven sub-bands (f1, f2, f3, f4, f5, f6,



and f7). A hexagon represents a cell. Adjacent cells use different frequencies.

Frequency reuse theory states that transmitted power attenuation of microwave on ground is about 4th power of distance. The transmission loss of radio signals is high and happens very fast. After signal transmitted at a certain power travels some distance, it ceases to interfere with the same frequencies beyond that distance.

As Figure 6 illustrates, CDMA adopts traditional cellular coverage. However, each cell uses the same frequency (or carrier).

F I G U R E 6 - CDMA FR E Q U E N C Y R E U S E

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

f1

In CDMA2000 1x systems, each bandwidth carrier is 1.25 MHz. All users in different cells use the same carrier to communicate. Since users use the same frequency, each user signal tends to interfere with the others. The system uses short PN code, 215-1 long to distinguish cells, Walsh code to distinguish channels, and long PN code, 242-1 long to distinguish channels from different terminals.

Due to the unified frequency reuse, signals of different users interfere with each other. Energy (power) determines location of user channel resources. Power decrease suppresses interference and increases capacity that makes power control very important to a CDMA system.

Power Control A unified frequency reuse requires effective user power control. Power control enables each user to receive and send information using minimum power. It suppresses user interference and reduces MS recharge time.

Chapter 3 - Key CDMA Technologies


If all MSs in a cell transmit signals at the same power, signals from MS near the BTS are strong, and those MSs far from the BTS are weak. As a result, the strong signals override the weak ones. In a CDMA system, stronger the power of signals transmitted by MS, easier it is for the MS to receive signals. However, the MS also interferes strongly with other MSs in the same band. Sometimes useful signals may deteriorate. As a result, the communication quality of other users deteriorates, lowering system capacity. To overcome this problem, adjustment of transmitter power on a real-time basis according to the communication distance becomes necessary. This is the concept behind power control.

In CDMA2000 1x systems, power control comprises reverse link power control, forward link control power or cell breath power control.

Reverse Link Power Control By adjusting the MS transmitter power, reverse link power control enables signals arriving at the base station receiver to possess the same power, SNR to reach threshold, and meet the requisite communication quality. Through power adjustment, signals of each MS have the same power on reaching the base station receiver regardless of MS location and transmitting environment.

Reverse link power control comprises reverse link open-loop power control, reverse link closed-loop power control, and reverse link outer-loop power control.

Reverse Link Open-loop Power Control Reverse link open-loop power control refers to the process wherein MS estimates path loss of the forward link as basis for judgment of reverse link loss by measuring signal power from the BTS, thereby determining its own transmitting power. Reverse open-loop power control eliminates average link loss and slow attenuation (caused due to shadow effect).

Reverse open-loop power control algorithm is as follows:

In the beginning, to prevent MS from transmitting high power in the access state, causing unnecessary interference, MS first uses the access trial program.

In reverse link traffic channel state, open-loop adjustment of the average output power of an MS varies only with the average input power. Open-loop power control provides a big dynamic range of ± 32 dB to compensate for average path loss and slow fading. In addition, the open-loop power control response time should be neither too fast nor too slow to avoid power wastage along with forward link fast fading. Generally, the response time constant is 20 ~ 30 ms, with an accuracy of ± 0.5 dB.

Reverse Link Closed-loop Power Control As forward and reverse link carrier frequencies are 45 MHz apart, reverse link contains losses present in the open loop and is independent of the forward link. Closed-loop power control technology implements accurate



power control for compensation. BTS auxiliary MS detects SNR (Signal to Noise Ratio) of the reverse traffic channel every 1.25 ms; compares it with a set threshold to generate the corresponding power control command, and sends it to the MS after inserting it into the forward traffic channel.

Reverse Link Outer Loop Power Control Reverse outer-loop power control enables dynamic adjustment of SNR

threshold 0NEb

in reverse link closed-loop power control. Outer-loop power control is the most characteristic part in reverse link power control. It effectively combines error frame ratio that affects voice quality with signal/noise ratio in the reverse closed-loop power control. Thus, power control enables capacity expansion, and improved voice quality.

There is no specific standard definition and description of reverse outer-loop power control, which means that reverse outer-loop power control design has great flexibility to provide different implementation methods.

During actual implementation, the three power control processes work in tandem, constituting the reverse link power control mechanism. MS Open-loop power control first conducts estimation on MS transmit power followed by closed-loop power control and then outer loop power control to further correct the open-loop estimation to achieve a more accurate power control.

Forward Link Power Control An effective forward link power control algorithm requires that it perform as quick a control as possible. The system selects the threshold control mode.

When MS moves to the cell edge, interference from the neighboring base stations become stronger.

When MS moves to the base station, multi-path interference becomes stronger.

The above interference affects signal reception, degrades communication quality, and even causes link setup failure. CDMA systems have power control introduced in the forward links. However, there is no forward power control in 1x EV-DO.

Forward link power control ensures communication quality of each user by reasonably allocating power to each forward traffic channel. It minimizes transmit power in the forward traffic channel as long as transmit power meets the minimum SNR required for MS demodulation. There is reduction in interference among traffic channels of adjacent cells, maximizing forward link user capacity.

In an ideal single cell model, forward link power control is not mandatory. Considering inter-cell interference and noise, forward power control is indispensable because it can overcome the following forward link communication abnormalities:



If distance between MS and its serving base station is almost the same as that between MS and one or more adjacent base stations, the interference from adjacent base stations is more pronounced. In addition, the interference change pattern from adjacent base stations is independent of the MS home base station signal strength. The home base station increases signal power by several decibels to maintain communication quality.

If MS is located at the converging point of strong multi-path interference signals, interference on the signal exceeds the permissible limit. In this case, the home base station is also required to increase the signal power sent to the MS.

If MS is located at a place with good signal transmission performance, there is a reduction in signal transmission loss. In this case base station reduces power of the signals sent to the MS, ensuring communication quality. Due to the limitation of base station transmission power, there is an increase in the capacity of forward links, and the interference to the users inside and outside the cell is suppressed.

Forward link power control comprises forward link closed-loop power control and forward link outer loop power control similar to reverse link power control. 1x system also features an additional forward link fast power control.

Forward Link Closed-loop Power Control The closed-loop power control compares Eb/Nt of forward traffic channel signals received with the related outer loop power control values and determines the power control bit value sent to the base station on the reverse power control sub-channel. Eb is the average bit energy, and Nt is the total noise, which includes white noise and interference from other cells.

Forward Link Outer Loop Power Control Forward link outer loop power control implementation takes place on the MS. The base station transmits outer loop power control threshold on the MS in the paging message. The threshold includes outer loop upper and lower thresholds and initial FCH and SCH threshold.

In the outer loop power control, threshold estimation is according to the target FER Eb/Nt of the assigned forward traffic channel. The base station closed loop sends this threshold or sent by messaging the base station if no closed loop exists. The base station controls the transmit power according to the received threshold.

Forward Link Fast Power Control On enabling the forward link outer loop power control, forward link outer loop power control and forward link closed loop power control function together to realize forward link fast power control.

Although forward link fast power control functions at the base station, MS obtains the outer-loop parameters and power control bit used for power



control for measuring forward link signal quality and transmitted to the base station through reverse pilot channel power control sub-channel.

Cell Breath Power Control As an important CDMA system function, the cell breath adjusts the load of cells in the system.

Forward link border refers to the physical base station positions. If MS moves to that position, the receiver provides the same performance regardless of the base station transmitting the signal. If MS is in the reverse link handoff border, receivers of two base stations have similar performance.

Base station cell breath control achieves forward link handoff border superposition and reverse link handoff border to maximize system capacity and prevent handoff failure.

Cell breath algorithm follows the principle that sum of base station reverse received power and the forward pilot transmit power remains constant. The algorithm controls cell coverage by adjusting the ratio of pilot signal power to the total base station transmission power.

Cell breath algorithm involves technologies such as initial state adjustment, reverse link monitoring and forward pilot frequency gain adjustment.

Diversity Reception In the narrowband modulation system, if the 1G cellular telephone system follows analog FM modulation, multiple paths cause serious fading.

In CDMA modulation system, different paths can receive signals separately, suppressing multi-path fading significantly. However, inability of the demodulator to handle multiple paths eliminates multi-path fading.

Diversity reception effectively prevents fading. It makes full use of multi-path signal energy in transmission and collects the energy dispersed in time domain, space domain, and frequency domain to improve transmission reliability.

Diversity falls into time diversity, space diversity, and frequency diversity. Deployment of these three types takes place in CDMA. The following introduces three kinds of diversity respectively.

Time Diversity MS movement causes Doppler frequency shift in the received signals. In multi-path environment, frequency shift leads to Doppler spread. Reciprocal value of Doppler spread defines coherence time. Signal fading occurs on transmission waveform specific to time and called time selective fading. It seriously affects bit error of digital signals.



Amplitude sampling in sequential order leaves the two sample points with long time interval (longer than the coherence time) irrelevant. Transmitting given signals N times within a certain time interval suppresses time diversity influence. Obtaining N independent diversity tributaries is possible as long as the time interval is longer than coherence time.

According to communication principle analysis, the time interval in the time domain Δt must exceed the coherence time in the time domain ΔT:

BTt 1=Δ≥Δ

B is the Doppler spread shift diffusion interval, which is directly proportional to the MS moving speed. Time diversity is irrelevant for MS in static state.

Compared with space diversity, time diversity uses fewer antennas. However, it uses more timeslot resources, decreasing transmission efficiency.

Frequency Diversity Frequency diversity modulates transmitted information into different carriers and sends them to corresponding channels. Since fading features frequency selectivity, interval between two frequencies is larger than the correlated bandwidth and mathematically represented as follows:

LFf 1=Δ≥Δ

Here, L refers to the power spectrum bandwidth of the received signal’s delay. The correlated bandwidth for the urban area and outskirts is 50 KHz and 250 KHz respectively, whereas the CDMA system signal bandwidth is 1.23MHz; leading to frequency diversity implementation.

If the frequency band is 800 MHz to 900 MHz in a city, and the typical delay diffusion is 5 μs:

The frequency diversity carrier interval is greater than 200 KHz.

Compared with space diversity, frequency diversity requires fewer receiving antennas and devices. However, frequency diversity occupies larger frequency spectrum. In addition, transmit end uses more transmitters.

Space Diversity In a base station, installation of several antennas with a certain interval enables reception and transmission of signals independently. Fading of each signal is irrelevant. Use of selective combination technology enables selection of output signal. It suppresses the influence of fading. This

KHzsLFf 200511 ===Δ≥Δ μ



method makes use of independence of signals received at different places (space) to prevent signal fading.

Basic space diversity structure involves installation of a single antenna at the transmitter end to transmit signals, and several antennas at the receiver end to receive signals.

Distance between receiving antennas is d. According to communication principles, d is the relevance interval ΔR, which satisfies the following expression:

ϕλ≥Δ= Rd

Here, λ refers to wavelength; and ϕ is the antenna diffusion angle. In urban areas, the diffusion angle ϕ is 20°.

λπλλπ 86.29)2(120360 ≈=××≥ ood

Greater the number of diversity antennas N, better the diversity.

Space diversity has the following types:

Polarity Diversity Signals sent by two antennas with polarity directions mutually perpendicular have few fading features. The polarity diversity makes use of this feature to achieve diversity effect. Installing a horizontally polarized antenna and a vertically polarized antenna at the transmit end perform polarity diversity of two signals with few fading features. Featuring compact structure, polarity diversity saves space. Transmit power is allocated to two antennas resulting in 3 dB loss.

Angle Diversity For different receiving environments involving parameters topography, geography, and buildings, the signals from different paths are vary. The angle diversity makes use of this feature to achieve diversity effect. Directional antenna can be installed at the receiving end directed at different directions.

In space diversity, there are N antennas at the receiving side. If the size and gain of these N antennas are the same, each antenna has a gain of 3 dB besides anti-fading diversity achieved by space diversity.

RAKE Receiver RAKE receiver follows space diversity technology. Buildings, hills, and other obstructions in the signal transmission path reflect spectrum signals sent by the transmitter. On reaching the receiver, each beam has a different delay forming multi-path signals. If these multi-path signal delays exceed the pseudo-code chip delay, the receiver can differentiate these beams. They pass these beams through different delay lines, align and combine them. The previous interference signals combine to become useful signals.



The RAKE receiver comprises searcher, finger, and combiner.

Searcher searches the path, making use of self-correlation and cross-correlation features of codes.

Finger de-spreads and demodulates the signals. Numbers of Fingers determine the paths demodulated. Normally RAKE receiver holds four fingers. An MS has three fingers.

Combiner combines the signals output from the fingers. The commonly used combination algorithms include selective-add combination, equal-gain combination, and maximum-ratio combination. The combined signals output to the decoder unit for channel decoding.

RAKE receiver adopts technologies such as pulse response measurement, code search, code tracking, complex amplitude estimation, and searcher. The following section details the RAKE receiver operation:

1. Pulse response measurement correlates different pilot code phases and received signals to find out the multi-path component.

The MS speed and radio environment determines the pulse response measurement speed. Faster the mobile station movement, so is the measurement speed for RAKE paths to obtain the best multi-path components. However, a broader scanning window is necessary in environments of longer delay extension.

Besides measurement, this module assigns multi-path components to RAKE paths. Multi-path assignment takes place after pulse response measurement completion or on finding strong multi-path component.

2. Code search refers to mobile station pilot signal scanning.

The nearest or adjacent pilot signals sequence determines the pilot signal priority. Search begins from the highest priority pilot signal when connection is lost due to some reasons.

Under strong interference influence, code search becomes a bottleneck. A filter performs fast code search.

Code search completion happens before system synchronization search.

3. Estimation of complex amplitude includes amplitude and phase.

In the maximum-ratio combination, signal weight is the complex conjugate of complex amplitude. Only phase error correction occurs in case of equal-gain combination. Each RAKE path requires equal weight consideration. Complex amplitude estimation averaging occurs in a reasonable time. Coherent time setting is as per upper limit of average time.

4. Searcher scans pilot signals of other cells.

During conversation, MS searches pilot signals, measures the downlink interference, and attempts to receive uplink interference results. It may take long time to notice the pilot signals of adjacent diversity as there are a large number of pilot signals.

Searching time may limit system performance especially in the micro cell environment where new base station activation occurs quickly because of corner effect. One possibility to limit the required hardware



is by flexibly assigning RAKE and searcher paths. A low multi-path environment increases the scanning effectiveness.

Soft Handoff Soft handoff is characteristic unique to CDMA mobile communication systems. When the MS moves to the area between adjacent BTSs, it can establish radio connection with the target BTSs without interrupting radio connection link with the source BTS. After establishing the target BTS connection, the MS releases the BTS source connection link. Soft handoff occurs between different sectors of the same BTS. Softer handoff occurs between sectors within the same BSC.

Following section introduces several important concepts related to soft handoff namely, pilot set, search window, and handoff parameters.

Pilot Set Just like standby handoff, CDMA system handoff has the pilot set concept. According to pilot PN sequence offset, MS classifies the pilot signals into four categories:

Active set: Pilot set corresponding to the current forward traffic channel.

Candidate set: The candidate set does not belong to the active set. However, the signals are strong enough for normal service processing.

Neighbor set: Pilot set designated by the neighboring base station cell list message.

Remaining set: Set of pilots excluded from the above three sets.

During pilot search, MS measures the pilot strength in the sequence of active set, candidate set, neighbor set, and remaining set. Assuming the active set and candidate set has PN1, PN2 and PN3, the neighboring set has PN11, PN12, PN13, and PN14, and the remaining set has PN', ..., MS measures the pilot signals in the following order:

PN1, PN2, PN3, PN11,



PN1, PN2, PN3, PN14, PN',


PN1, PN2, PN3, PN12, ...

The probability to search pilots in the remaining set is less probability compared to those in the active set and candidate set.



Search Window Besides the number of pilot searching times, another factor considered is the search range. When MS communicates with the base station, there is delay. As Figure 7 illustrates, the signal delay between AT and BS1 is t1, and that between the AT and BS2 is T2.

F I G U R E 7 - D E L AY D I F F E R E N C E B E T W E E N BS S

Assuming AT is synchronous with BS1, if the distance between AT and BS1 is shorter than that between the AT and BS2, t1 must be shorter than t2 (t1 < t2). BS2 pilot signal reaches t2-t1 time later to the AT than reference time. If the distance between the AT and BS1 is longer than that between the AT and BS2, t1 must be longer than t2 (t1 > t2). Pilot signal of BS2 appears t1-t2 to the AT, ahead of reference time.

When detecting pilot strength, the AM searches in a range to avoid loss of any pilot signal in each set. AT uses the search window to capture the pilot. AT sets an offset for a PN sequence and search for pilots ahead or behind a chip time segment.

As Figure 8 illustrates, AT uses short code phase as the center and searches for pilot signals in the short code range ahead and behind half the search window.

F I G U R E 8 - S E AR C H W I N D O W AN D P I L O T S I G N AL

Larger the search window, slower is the search. However, if the search window is too small, the pilot with large delay may escape the search. For each pilot set type, base stations define the search window size for ATs.

SRCH_WIN_A: Pilot search window size for active set and candidate set.



SRCH_WIN_N: Pilot search window size for the neighboring set.

SRCH_WIN_R: Pilot search window size for the remaining set.

SRCH_WIN_A is set according to transmission environment forecast. It must be large enough to capture all multi-path pilot signals of the target base station. It must also be small enough to optimize the search window performance.

Generally, SRCH_WIN_N is larger than SRCH_WIN_A. Its size is set according to the physical distance between current base station and neighboring base station. It is normally larger than two times of the maximum signal delay.

Generally, SRCH_WIN_R setting is similar to SRCH_WIN_N. If not using the remaining set, set the SRCH_WIN_R to a very small value.

Handoff Parameters T_ADD: Pilot signal monitoring threshold. When MS detects base

station pilot strength of a neighboring set or remaining set is higher than T_ADD, it adds pilot to the candidate set.

T_DROP: Deteriorated pilot signal threshold monitoring. When MS detects that pilot strength of the active set or candidate set base station is lower than T_DROP, it activates the related base station handoff drop timer.

T_TDROP: Deterioration of timer preset value of the timer that monitors the pilot signal. If the strength of the pilot in the active set falls below T_DROP, MS activates T_TDROP timer. If timer expires, the pilot returns to the neighboring set from the active set. If the pilot strength rises above T_DROP before T_TDROP timer expires, the timer gets deleted automatically.

T_COMP: Threshold comparison between pilot signal strength in the active set and candidate set. When MS detects that the base station pilot strength in the candidate set is T_COMP x 0.5 dB higher than the pilot strength in the active set, it sends a pilot strength measurement message (PSMM) and starts handoff.

Receiver calculates pilot signal Eb/Io value searched as pilot strength. Figure 9 illustrates the soft handoff flow.



F I G U R E 9 - S O F T H AN D O F F FL O W

NeighborSet

CandidateSet

Active SetNeighbor

SetCandidate

Set

1 2 3 4 5 6 7 8

PilotStrength

T_ADD

T_DROP

time

P1

P2

P2

P1

As Figure 9 illustrates, P1 is the source cell pilot, and P2 is the target cell pilot.

1. On detecting P2 strength higher than T_ADD, MS moves it to the candidate set.

2. On detecting P2 strength higher than [(SOFT_SLOPE/8) x 10 x log10 (PS1) +ADD_INTERCEPT/2], MS sends a Pilot Strength Measurement Message to the base station.

3. MS receives Extended Handoff Direction Message returned by the base station, adds P2 into the active set, and sends a Handoff Complete Message.

4. On detecting P1 weaker than [(SOFT_SLOPE/8) x 10 x log10 (PS2) +DROP_INTERCEPT/2], MS activates the T_TDROP timer.

5. On detecting T_TDROP timer expiry, MS sends Pilot Strength Measurement Message to the base station.

6. MS receives Extended Handoff Direction Message returned by the base station, moves P1 to the candidate set, and sends a Handoff Complete Message.

7. On detecting P1 weaker than T_DROP, MS activates T_TDROP timer.

8. On detecting T_TDROP timer expiry, MS moves P1 from candidate set to neighbor set.

Base station implements softer handoff without notifying the MSC. For a mobile station, the received signals from antennas of different sectors are like multi-path components from the base station point of view. These signals combine into one voice frame and sent to the selector as base station voice frame. MSC implements soft handoff. Selector receives all base station signals and chooses the best signal for voice encoding/decoding.





C h a p t e r 4

CDMA2000 1x

This chapter explains: CDMA2000 1x channels.

CDMA2000 1x service flows.

System Overview CDMA2000 is one of the 3G mobile communication radio transmission technology standards recommended by ITU. According to the bandwidth used, CDMA2000 comprises 1x system and 3x system. 1x system uses 1.25 MHz bandwidth and provides data services up to 307.2 Kb/s. From this aspect, CDMA2000 1x is part of 2.5G system.

Difference between CDMA2000 1x system and CDMA2000 3x system is that the latter follows multi-channel carrier technology. CDMA2000 3x system uses three carriers to expand bandwidth.

A complete 1x system comprises network subsystem (NSS), base station subsystem (BSS), and mobile station (MS).

CDMA2000 1x system supports data transmission up to 307.2 Kb/s. Network section introduces packet switching. It also supports mobile IP service. As a new bearer service developed from the current IS-95 system, IP service aims to provide data services in the packet IP form to all CDMA users.



Air Interface Parameters Table 4 describes CDMA2000 1x system air interface parameters.

TAB L E 4 - AI R I N T E R F AC E P AR AM E T E R S O F CDMA2000 1 X S Y S T E M

Parameter Value

Interval between uplink and downlink 45 MHz

Wavelength About 36 cm

Frequency width 1230 KHz

Working mode FDD

Modulation modes QPSK and HPSK

Voice coding CELP

Voice coding rate 8 Kb/s

Transmission rate 1.2288 Mb/s

Bit time 0.8 μs

Forward Channels Figure 10 illustrates CDMA2000 1x system forward channels.

F I G U R E 10 - CDMA2000 1 X FO R W AR D C H AN N E L S

Table 5 describes functions and features of forward channels in the CDMA2000 1x system.

Chapter 4 - CDMA2000 1x


TAB L E 5 - FU N C T I O N S AN D FE AT U R E S O F CDMA2000 1 X FO R W AR D C H AN N E L S

Channel Functions

Forward Pilot Channel (F-PICH) Broadcasts frequency and phase information of the base station, helping terminals to perform coherent demodulation.

Forward Synchronization Channel (F-SYNC)

Broadcasts synchronization information and system parameters of the base station.

Forward Paging Channel (F-PCH)

Broadcasts paging terminal information and system parameters of the base station, and transfers commands issued by the base station.

Forward Traffic Channel (F-TCH) Transmits voice and data services.

Forward Common Assignment Channel (F-CACH)

Transmits assignment information for rapid response of reverse channel and supports random access packet transmission on reverse links.

Forward Common Power Control Channel (F-CPCCH)

Controls R-CCCH power when working in the power controlled access mode. Controls R-CCCH transmission power when working in reservation access mode.

Forward Common Control Channel

Sends messages (paging message, response, channel assignment message, and short data burst) to designated MS.

Forward Broadcast Control Channel (F-BCCH)

Sends common overhead message and short messages to the system.

Forward Quick Paging Channel (F-QPCH)

Base station uses this channel to indicate the timeslot where the MS receives the control message of the F-PCH or F-CCCH quickly. The MS need not take time to monitor the F-PCH or F-CCCH timeslot. It helps save MS power.

Reverse Channels Figure 11 illustrates CDMA2000 1x system reverse channels.

F I G U R E 11 - CDMA2000 1 X R E V E R S E C H AN N E L S



Table 6 describes functions and features of reverse channels in CDMA2000 1x system.

TAB L E 6 - FU N C T I O N S AN D FE AT U R E S O F CDMA2000 1 X R E V E R S E C H AN N E L S

Channel Functions

Reverse Access Channel (R-ACH)

Through R-ACH, MS originates communication with base station and responds to paging channel messages from the base station.

Reverse traffic channel (R-TCH RC1 – RC2)

During call processing, MS sends user information and signaling messages through R-TCHs to the base station.

Reverse Enhanced Access Channel (R-EACH)

Prior to establishing traffic channel, MS sends control messages to the base station through R-EACH. It improves the MS access capability.

Reverse Common Control Channel (R-CCCH)

Prior to establishing traffic channel, MS sends control messages and short data bursts to the base station through R-CCCH.

Reverse Traffic Channel (R-TCH RC3 – RC6)

During call proceeding, MS sends user information and signaling messages through R-TCHs to the base station.

Technical Features CDMA2000 1x system is backward compatible with IS-95 system. However, compared with the IS-95 system, CDMA2000 1x system provides the following new features:

Radio Part Various channel bandwidths: CDMA2000 1x system supports Multi-

carrier (MC) and Direct Spreading (DS) in forward links, and supports DS in reverse links. In MC mode, it supports multiple RF bandwidths. The RF bandwidth can be N x 1.25 MHz where N takes values such as 1, 3, 5, 9, or 12.

Forward transmit diversity: CDMA2000 1x transmit diversity divides data into two parts, spread spectrum using different Walsh codes, and transmitting data using their own antenna.

Forward link fast power control: CDMA2000 1x implements forward link fast power control. According to the measured forward traffic channel strength, the terminal sends commands to the base station to adjust the base station transmission power.

Turbo code: CDMA2000 1x system follows Turbo code to perform channel coding, and improved error correction capability.

Reverse pilot channel and reverse link coherent demodulation: CDMA2000 1x system provides reverse pilot channel, enabling coherent demodulation on reverse channels and increasing reverse link capability.



Flexible frame length: CDMA2000 1x channels support various frame lengths including 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, and 160 ms.

With new features added, the CDMA2000 1x system is backward compatible with IS-95 system. Its baseband system uses Radio Configuration (RC) to realize compatibility. Different radio configurations determine different baseband processing modes like coding, interleaving, and error correction.

RC1 and RC2 are same as IS-95 system. Radio configurations higher than RC2 are new additions to the 1x system.

When establishing a call, the related service negotiation program determines the use of RC.

For the voice services, IS-95 MSs work in the 1x system carrier frequency range, 1x MSs work in the IS-95 carrier frequency range.

Network Part Enhanced A1 interface: Supports concurrent services and emergency

call.

Introducing user area: Providing different services for users in different geographical areas.

A10/A11 interface: Supports packet data.

Security association between Packet Control Function (PCF) and Packet Data Serving Node (PDSN): Supports secure and reliable transmission.

Mobile IP: Supports packet data mobility between PDSN and FA.

Provides triangle positioning.

Service Flows CDMA2000 1x service flows include voice, data, and PTT service flow.

MS and BSS implements service flows by exchanging messages in a CDMA network.

Voice Service Typical service flows in voice service include:

MS-originated call (MOC)

MS-terminated call (MTC)

Release originated by MS

Release originated by BSS

Release originated by the Mobile Switching Center (MSC).



MOC Figure 12 illustrates MOC flow.

F I G U R E 12 - MOC FL O W

A. MS sends Origination message from the access channel of air interface to BSS and requests BSS to respond.

B. Upon receiving Origination message, BSS sends a BS Ack Order message to MS.

C. BSS constructs and encapsulates CM Service Request message, and sends it to MSC. For calls requiring circuit switching, BSS also requires terrestrial circuit in that message, and requests MSC to allocate that circuit.

D. MSC sends an Assignment Request message to BSS, requesting the BSS to allocate radio resources. If MSC supports terrestrial circuit recommended by BSS in the CM Service Request message, it assigns that circuit in the Assignment Request message. Else, it assigns another terrestrial circuit.

E. Following MS traffic channel assignment, BSS sends a Channel Assignment Message or Extended Channel Assignment Message through the paging channel, and starts establishing the radio traffic channel.



F. MS sends the Traffic Channel preamble (TCH Preamble) on the reverse traffic channel designated.

G. After capturing the reverse traffic channel, BSS then sends a BS Ack Order on the forward traffic channel and requests MS to reply.

H. MS sends MS Ack Order message on the reverse traffic channel as response to BS Ack Order sent by BSS.

I. BSS sends a Service Connect message or Service Option Response Order to MS, designating service configuration for the call.

J. Upon receiving Service Connect message, the MS processes services according to service configuration designated, and sends a Service Connect Completion message as response.

K. After establishing radio traffic channel and terrestrial circuit connection, BSS sends an Assignment Complete message to MSC, and assumes that the call is in conversation state.

L. When in-band is in call processing tone, MS receives ring back tone through voice circuit.



MTC Figure 13 illustrates MTC flow.

F I G U R E 13 - MTC F L O W

A. When the paged MS is in the MSC service area, MSC sends a Paging Request message to the BSS to trigger call setup flow.

B. BSS sends a General Page Message carrying MS identification code through the paging channel.



C. After recognizing paging request containing its identification code on the paging channel, MS sends a Page Response message to the BSS through the access channel.

D. BSS constructs a Paging Response message using the information received from MS, encapsulates it and sends it to the MSC. BSS requires the terrestrial circuit in that message and requests the MSC to assign the circuit.

E. Upon receiving Paging message, the BSS sends a BS Ack Order to MS.

F ~ M. Similar to steps D to K in MOC flow.

N. BSS sends an Alert with Info message to MS indicating the MS to ring.

O. After receiving the Alert with Info message, MS sends MS Ack Order message to the BSS.

P. MS responds to this call (off hook) and sends a Connect order message carrying layer 2 verification request to the BSS.

Q. Upon receiving Connect Order message, BSS sends a BS Ack Order to MS on the forward traffic channel.

R. BSS sends a Connect message to the MSC notifying the MSC that MS has responded to this call. Calling and called party can start conversing.

Call Release Originated by MS After initiating network access, MS originates the release due to service request. For instance, in a case when the user hooks up. Figure 14 illustrates the flow.

F I G U R E 14 - MS OR I G I N AT E D R E L E AS E FL O W

A. MS sends a Release Order message on the reverse channel to originate a release.

B. BSS sends a Clear Request message to MSC.

C. MSC sends a Clear Command message instructing BSS to release associated resources such as terrestrial circuit.

D. BSS sends Release Order message to MS, and then releases radio resources.



E. After receiving the Clear Command message from MSC, BSS releases the terrestrial circuit resources assigned and returns a Clear Complete message. Upon receiving the Clear Complete message, MSC releases the SCCP connection transmission connection in the lower layer.

Call Release Originated by BSS When the radio connection between MS and BSS fails due to MS inactivation or the call fails due to BSS equipment damage, BSS sends release request to the MSC to trigger call release flow. Figure 15 illustrates the release flow originated by BSS.

F I G U R E 15 - BSS OR I G I N AT E D R E L E AS E FL O W

A. In case of link failure or non-active MS, BSS sends Clear request message to MSC.

B. MSC sends a Clear Command message, instructing BSS to release associated resources such as terrestrial circuit.

C. Upon receiving Clear Command, BSS replies with a Clear Complete message. After receiving the message, MSC releases SCCP transmission in the lower layer.



Call Release Originated by MSC Figure 16 illustrates release flow originated by MSC.

F I G U R E 16 - MSC OR I G I N AT E D C AL L R E L E AS E FL O W

MS

A

B

C

D

BSS MSC

Release Order

Clear Command

Release Order

Clear Complete

A. MSC sends a Clear Command to BSS instructing BSS to release associated resources and initiate call release flow at Um interface.

B. BSS sends Release Order message on the reverse channel to initiate call release operation.

C. After receiving Release Order, MS sends a reply on the reverse channel.

D. BSS sends a Clear Complete message to MSC. After receiving the message, MSC releases the SCCP transmission connection in the lower layer.

Data Service Following user states define CDMA2000 1x data service flows:

Active state: With air traffic channel between MS and base station, data can be sent on both sides, maintaining A1, A8, and A10 connections.

Dormant state: There is no air traffic channel but a PPP link between MS and base station leads to A1 and A8 link release, while maintaining A10 link.

Null state: There is neither air traffic channel nor PPP link between MS and base station resulting in release of A1, A8, and A10 links.



MOC Figure 17 illustrates MOC flow.

F I G U R E 17 - MS OR I G I N AT E D D AT A S E R V I C E C AL L FL O W

A. MS sends an Origination message to BSS through the access channel of air interface.

B. After receiving the Origination message, BSS sends a BS Ack Order message to MS.

C. BSS constructs a CM Service Request message and sends it to MSC.

D. MSC sends an Assignment Request message to BSS requesting BSS to assign radio resources.

E. BSS sends a channel assignment message through the paging channel of air interface.



F. MS sends TCH preamble over the assigned reverse traffic channel.

G. After obtaining the reverse traffic channel, BSS sends a BS Ack Order message to the MS through forward traffic channel.

H. After receiving BS Ack Order, MS sends an MS Ack Order and transmits null traffic frame on the reverse traffic channel.

I. BSS sends a Service Connect message or service select response message to the MS designating traffic configuration for the call. MS processes services according to the designated traffic configuration.

J. After receiving Service Connect Message, MS sends a Service Connect Complete message.

K. BSC sends A9-Setup-A8 message to the PCF requesting for A8 connection.

L. PCF sends A11-Registration-Request message to PDSN requesting for A10 connection.

M. After receiving A10 connection request, PDSN returns with A11-Registration-Reply to PCF.

N. PCF returns A9-Connect-A8 message to BSS, successfully establishing A8 and A10 connections.

O. After establishing radio traffic channel and terrestrial circuit, BSS sends an Assignment Complete message to MSC.

P. MS negotiates with PDSN to set up PPP connection. Establishing mobile IP connection is necessary for mobile IP access mode. PPP message and Mobile IP message transfer takes place on traffic channel, and is transparent to BSS/PCF.

Q. Following PPP connection set up, data service is in connected state.



Call Release Originated by MS Figure 18 illustrates MS-originated call release flow.

F I G U R E 18 - MS OR I G I N AT E D C AL L R E L E AS E FL O W

A. MS sends Release Order message to BSS through the dedicated control channel of air interface.

B. Upon receiving the message, BSS sends a Clear Request to MSC.

C. When releasing resources at the network side, MSC sends a Clear Command to BSS.

D. Upon receiving Clear Command message, BSS sends a Release Order to MS.

E. BSS sends A9-Setup-A8 message to PCF requesting PCF to release A8 connection.

F. PCF sends an activation termination settlement record in the A11-Registration-Request message to PDSN.

G. PDSN returns the A11-Registration-Reply message.

H. PCF sends A9-Release-A8 Complete message to confirm release of A8 connection, enabling connection release.

I. BSS sends a Clear Complete message to MSC indicating release completion.



Inter-PCF Dormant Handoff in PDSN Figure 19 illustrates the inter-PCF dormant handoff flow in PDSN.

F I G U R E 19 - PDSN I N T E R -PCF D O R M AN T H AN D O F F

MS

A

B

C

D

Source BSS

F

TargetPCF

G

H

I

J

K

L

E

M

N

O

P

Q

MSC PDSNTarget BSS Source PCF

Origination message

BS Ack Order

CM Service Request

Assignment Request

A9-Setup-A8

A11 -Registration-Request

A11- Registration- Reply

A9-Release-A8 Complete

Assignment Failure

Clear Command

Clear Complete

A11- Registration-Update

A11- Registration - Ack

A11- Registration -Request

A11- Registration- Reply

Dormant Packet Data Session

Dormant, PPP connection is maintained

A. Packet data service connection is in dormant state.

B. MS sends an Origination message to BSS through access channel of air interface.



C. Target BSS sends BS Ack Order to MS after receiving Origination message.

D. Target BSS constructs CM Service Request and sends it to MSC.

E. MSC sends an Assignment Request to the target BSS requesting BSS to assign radio resources.

F. Target BSS sends A9-Setup-A8 (DRS = 0) message to the target PCF.

G. Target PCF sends A11-Registration-Request to the PDSN to set up A10 connection.

H. PDSN replies with A11-Registration-Reply message.

I. Target PCF sends A9-Release-A8 Complete message to the target BSS.

J. Target BSS sends Assignment Failure to MSC with cause value of Packet Call Going Dormant.

K. MSC sends a Clear Command message with cause value Do Not Notify Mobile to target BSS.

L. Target BSS returns Clear Complete message to MSC.

M. PDSN sends A11-Registration-Update message to the source PCF requesting PCF to release original A10 connection.

N. Source PCF acknowledges A10 connection release request with A11-Registration-Ack message.

O. Source PCF sends A11-Registration-Reply (Lifetime = 0) to release A10 connection.

P. For valid A11-Registration-Request message, PDSN returns A11-Registration-reply message with receive indication and lifetime value. Before returning A11-Registration-Reply message, PDSN saves billing related information.

Q. Packet data service session is in dormant state.



Inter-PCF Active Handoff in PDSN Figure 20 illustrates inter-PCF active handoff flow in PDSN.

F I G U R E 20 - PDSN I N T E R -PCF AC T I V E H AN D O F F

MS

A

B

C

D

Source BSS

F

Target PCF

G

H

I

J

K

L

E

M

N

O

P

Q

MSC PDSNTarget BSSSource PCF

R

S

T

U

V

W

X

Handoff Required

Handoff Request

A9-Setup-A8

A9-Connect-A8

Handoff Request Ack

Handoff Command

A9- AL Disconnected

A9- AL Disconnected Ack

G HDM / UHDM

MS Ack Order

Handoff Commenced

Handoff completion

BS Ack Order

A9- AL Connected

A11-Registration-Request

A11-Registration-Reply

A9- AL Connected Ack

Handoff complete

Clear Command

A9-Release-A8

A11-Registration-Request(lifetime=0)

A11-Registration-Reply

A9-Release-A 8 complete

Clear Complete

A. MS reports signal strength in the target cell exceeds network-designated threshold. The source BSS requests target cell to hard handoff



according to MS report. It sends a handoff request message containing cell list to MSC.

B. Since handoff request already indicates hard handoff, MSC sends a handoff request message to the target BSS.

C. Target BSS sends A9-Setup-A8 message to the target PCF to establish A8 connection.

D. Target PCF sends A9-Release-A8 Complete message to the target BSS.

E. Target BSS sends Handoff Request Ack message to MSC.

F. MSC prepares handoff from source BSS to the target BSS, and sends Handoff Command to the source BSS.

G. Source BSS sends A9-AL-Disconnected message to the source PCF. Source PCF stops sending data to source BSS.

H. Source PCF returns A9-AL-Disconnected Ack message to source BSS.

I. Source BSS sends an extended or general handoff command through the air interface to MS. If MS allows the return to source BSS, source BSS starts the timer.

J. MS sends MS Ack Order to source BSS as response to the extended or general handoff command.

K. The source BSS sends a Handoff Commenced message to MSC, notifying MSC the MS hand off to the target BSS channel.

L. MS sends a Handoff Completion message to the target BSS.

M. Target BSS sends BS Ack Order to MS.

N. Target BSS sends A9-AL-Connected message to the target PCF.

O. Target PCF sends A11-Registration-Request to PDSN requesting set up of A10 connection.

P. After receiving A10 connection request, PDSN returns A11-Registration-Reply message to the target PCF.

Q. Target PCF sends A9-AL-Connected Ack message to the target BSS.

R. Target BSS sends Handoff Complete message to MSC, notifying the MSC of the successful MS handoff.

S. MSC sends a Clear Command message to the source BSS to clear all resources.

T. Source BSS sends A9-Release-A8 message to the source PCF to release A8 connection between source BSS and source PCF.

U. Source PCF sends A11-Registration-Request (Lifetime = 0) message to PDSN seeking release of the old A10 connection.

V. After receiving A10 connection release request, PDSN returns an A11-Registration-Reply message to the source PCF.

W. Source PCF returns A9-Release-A8 Complete message to the source BSS.

X. Source BSS sends MSC a Clear Complete message notifying the MSC of clear completion.


C h a p t e r 5

CDMA2000 1x EV-DO

This chapter explains: CDMA2000 1x EV-DO Reverse link channels.

CDMA2000 1x EV-DO service flows.

System Overview EV-DO in CDMA2000 1x EV-DO is an acronym for Evolution Data Optimized or Evolution Data Only. High-speed data transmission necessitated the evolution from CDMA2000 1x to CDMA2000 1x EV-DO. Qualcomm and Lucent jointly developed the 1x EV-DO specification IS-856.

1x EV-DO system structure involves a new radio network part overlaying the 1x system. 1x system provides voice services and low/medium-speed data services. 1x EV-DO system provides high-speed packet data services. 1x EV-DO and 1x systems use different carriers to transfer data. Optimizing voice and high-speed packet data services helps achieve optimum performance.

At the same narrowband CDMA frequency bandwidth, 1x EV-DO provides the highest data transmission up to 3.1 Mb/s.

Since 1x EV-DO evolved from 1x systems, it inherits the 1x system radio features. It is equivalent to the new frequencies of 1x system. 1x EV-DO system RF equipment is compatible with 1x system.

Network Model 1x EV-DO network model has two developing routines; interoperability specification for High Rate Packet Data Access (HRPDA) Network Interface Revision 0 and Revision A. Difference between the two models is the presence or absence of SC/MM (Spread Carrier/Mobility Management) function in PCF.

Figure 21 and Figure 22 illustrate the 1x EV-DO network model.



F I G U R E 21 - CDMA2000 1 X EV-DO NETWORK MODEL (R E V I S I O N 0 )

F I G U R E 22 - CDMA2000 1 X EV-DO N E T W O R K M O D E L (R E V I S I O N A)

System Features 1. Voice service requirements are different from those of data services.

Table 7 describes the data service requirements.

TAB L E 7 - D AT A S E R V I C E R E Q U I R E M E N T S

Item Data Service

Delay (total processing time)

It is not possible to sense the delay changes of several seconds.

Bit Error Ratio (BER) BER Error correction coding technology reduces BER.

Forward & reverse data rate

The forward link rate requirement is several times of reverse link rate. Forward data rate is 38.4 Kb/s ~ 3.1 Mb/s, and reverse data rate is 4.8 Kb/s ~ 1.8 Mb/s.

Throughput Base station packet data throughput is high. It depends on number of users served and the environment interference level.

2. 1x EV-DO system is compatible with IS-95/1x network.

Chapter 5 - CDMA2000 1x EV-DO


As Figure 23 illustrates, 1x EV-DO system bandwidth is 1.25 MHz, which has the same spectrum features of IS-95/1x.

F I G U R E 23 – 2000 1 X AN D 1 X EV-DO S P E C T R U M FE AT U R E S

1x EV-DO system deployment uses existing sites, towers, antennas, with specific working frequencies alongside IS-95/1x systems without changing network plan.

Forward Channels Forward links from AN to AT provide communication between ATs in the AN. Forward links have the following 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.

As an independent system, 1x EV-DO system follows a completely new channel structure.

Figure 24 illustrates the CDMA2000 1x EV-DO system forward channels.



F I G U R E 24 - CDMA2000 1 X EV-DO FO R W AR D C H AN N E L S

Table 8 describes the functions and features of CDMA2000 1x EV-DO system forward channels.

TAB L E 8 - FU N C T I O N S AN D FE AT U R E S O F CDMA2000 1 X EV-DO FO R W AR D C H AN N E L S

Channel Functions

Pilot Channel (Pilot) Transmits pilot signals from AN to AT. The pilot signals carry out system capture, clock synchronization, demodulation, decoding, and C/I estimation.

Reverse Activity (RA) channel dynamically controls the reverse channel load.

Inability of AN to receive DRC information from ATs results in DRC Lock channel notifying specific ATs to stop sending DRC information to the AN.

Forward Medium Access Control Channel (Medium Access Control)

Reverse Power Control (RPC) channel performs AT power control that sends data on the reverse channel.

Forward Traffic Channel (Traffic) AN sends user data on traffic channels.

Forward Control Channel (Control)

Control channel sends broadcast system common configuration parameter messages from AN to AT. Non-activation of traffic channels results in Control channel sending signaling messages to the specific AT.



Reverse Channels Forward links (from AT to AN) provide the communication between ATs and the AN. Following are the 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. Figure 25 illustrates CDMA2000 1x EV-DO system reverse channels.

F I G U R E 25 - CDMA2000 1 X EV-DO R E V E R S E C H AN N E L S



Table 9 describes the functions and features of CDMA2000 1x EV-DO system reverse channels.

TAB L E 9 - FU N C T I O N S AN D FE AT U R E S O F CDMA2000 1 X EV-DO R E V E R S E C H AN N E L S

Channel Functions

Reverse access channels

Includes reverse pilot channel and data channel, through which ATs originate calls or respond to AN paging message.

The pilot channel enables coherent demodulation.

RRI sub-channel indicates the rate of data transmitted on the data channel of reverse traffic channel. Medium

Access Channel (MAC)

AT uses DRC sub-channel to indicate forward traffic channel data rate requested and the service sector selected by the forward channel. DRC channel carries two kinds of information: DRC Value and DRC Cover.

AT uses ACK channel to notify AN correct reception of forward traffic channel data packets. If incorrectly demodulated, AT sends the NAK bit.

Reverse traffic channels

Data channel transfers reverse service data packets.

Key 1x EV-DO Technologies This section introduces key 1x EV-DO system technologies.

Reverse Link Power Control Power control maximizes system capacity. In 1x EV-DO system, there is no forward link power control because forward link power is constant. Reverse link follows power control.

Reverse link power control aims to control output power of ATs while minimizing interference, maintaining high reverse data link quality. When reverse link signal-to-noise ratio (SNR) per user is lowest for acceptable performance, capacity is highest.

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. The system must control the load on reverse links to avoid too many users in the same sector transmitting data to AN at a high rate. This leads to all ATs becoming unavailable.

AN follows the two mechanisms described to control the AT transmit rate:

Reverse rate limit (RRL): AN restricts the maximum reverse rate of AT to a level below 307.2 Kb/s using BroadcastReverseRateLimit or UnicastReverseRateLimit.



Reverse activated bit (RAB) and transition probability. On detecting low reverse link load, the sector sets RAB to 0. ATs in that sector increase the reverse rate according to a group of probable values like Transition009k6_019k2, Transition019k2_038k4, Transition038k4_076k8, and Transition076k8_153k6. On detecting that high reverse link load, the sector sets RAB to 1. All ATs must decrease the transmit rate according to a group of probable values Transition019k2 _ 009k6, Transition038k4 _ 019k2, Transition 076k8 _038k4, and Transition153k6_076k8. If AT is in soft handoff mode, any sector with RAB of 1 can decrease AT rate.

The key to reverse link rate control is to determine reverse link busy or idle state. A more accurate method is to measure Rise over Thermal (ROT) at the receiving antenna of each sector.

Forward Link TDM Different from 1x TDM, 1x EV-DO forward links follow Time Division Multiplexing (TDM) to serve all ATs. Within the same sector, one timeslot can serve one user only.

Same as IS-95/1x, 1x EV-DO forward pilot channel helps AT complete channel estimation in system capture and demodulation.

In 1x EV-DO systems, AT determines the serving sector and maximum sector rate. Measuring forward pilot and radio channel quality of ATs determine its implementation standards. Since all BTSs send pilot at the same time, and the pilot transmits at full power, AT can calculate accurate pilot strength and reflect BTS signals and interference rapidly.

Forward Link Scheduling Strategy To ensure maximum service rate provision to users, AT requests for the best data rate according to C/I measured in the AN. According to the AT request, AN determines the service provided to different users through scheduling algorithm.

Purpose of scheduling algorithm is to maximize system throughput and ensure service provisioning to all users. Due to radio environment complexity, AT informs the system of the highest acceptable data rate through the DRC channel. In the process of reaching maximum throughput, the system sends data to the AT that reports maximum DRC Value. However, other users are unable to use system services. The scheduling algorithm aims to equalize throughput.

Forward Link Virtual Soft Handoff Besides supporting various soft/softer handoffs like 1x system, 1x EV-DO introduces a new handoff — forward virtual handoff.

Forward virtual handoff enables only one sector to send data through forward channel to the terminal at any time in the active set through forward channel. According to received pilot signals quality, the terminal uses DRC cover of DRC channel to designate the sector expected to send



data. All sectors in the active set monitor reverse channel of the terminal. Upon receiving DRC channel, the network determines serving sector of the terminal. During forward virtual handoff, the terminal does not exchange any signaling with the network. Entire handoff flow is very fast. In addition, handoff requires use of only forward air resources of one sector. It increases utilization of forward channels.

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 3.1 Mb/s. High-speed data transmission on 1.25 MHz is because of high modulation and demodulation order as well as the error correction coding technology.

R-P Session Establishment In 1x EV-DO network, since routing does not use IMSI and MIN, 1x EV-DO AT need not allocate IMSI/MIN in advance. R-P session handoff between BSC and PDSN necessitates a new solution. Successful transfer session between BSCs in the same PDSN requires IMSIs of ATs to be the same.

Since AT has no IMSI, a session initiated between AT and PDSN leads BSC to assign an IMSI to AT. 1x EV-DO standard introduces the new A12 interface, which interfaces BSC and AN-AAA server.

The AN-AAA implements the following functions:

1. AT authentication implementation.

2. Sending IMSI in the authentication accept message to BSC. This IMSI establishes R-P session between BSC and PDSN.

If not deploying AN-AAA server in the 1x EV-DO network, the BSC uses other methods to allocate IMSI to ATs. However, IMSI must be unique in the entire network. Without AN-AAA server, the R-P session handoff implementation between 1x EV-DO BSC and 1x BSC is not possible. AT can use mobile IP only to keep its IP address unchanged when passing through the network edge. AN-AAA deployment enables fast handoff and improves AT performance when passing through the network edge.

Service Flow According to the functions, 1x EV-DO services comprise session management service and connection management service. This section describes service flows.

Session Management AT cannot obtain any service in the 1x EV-DO network unless it sets up a session with AN. Session management involves UATI assignment and maintenance, session negotiation, and session release.



UATI Assignment and Maintenance Access Network (AN) allocates 128 bits long unique identifier Unicast Access Terminal Identifier (UATI) to AT. The UATI assignment is the first step for establishing session. It indicates an open session between AT and AN. The session uses default system configuration. Figure 26 illustrates UATI assignment flow.

F I G U R E 26 - UATI AS S I G N M E N T FL O W

AT

A

B

C

D

AN

E

UATIRequest

ACAck

UATIAssignment

UATIComplete

ACAck

Following describes the UATI assignment flow:

A. AT sends UATIRequest message through the access channel to AN requesting for UATI.

B. AN returns ACAck message.

C. AN assigns UATI and sends it to AT in UATIAssignment message.

D. AT sends a UATIComplete message to AN indicating completed UATI assignment.

E. AN returns ACAck message.

AT and AN can originate UATI update during the session.

Session Negotiation In the course of establishing a session, AT and AN need to negotiate communication configuration, including protocol and protocol parameters used. Successful session set up takes place when AT and AN reaches agreement on negotiation. The configuration after negotiation will be valid for the following connection. Figure 27 illustrates the negotiation flow.



F I G U R E 27 - S E S S I O N N E G O T I AT I O N FL O W

UATI session negotiation flow is as follows:

A. AT and AN use default configuration to start a connection and perform session negotiation preparation.

B-G. AT originates protocol negotiation.

H-K. AT originates protocol negotiation. Here Type X and Type Y stand for the protocols to which the parameters negotiated belong.

L. Completed negotiation originated by AT.

M. AN and AT exchange key, which is used for AT authentication during the session.

N-Q. AN originates negotiation.

R. Completed session negotiation.

Session Release In 1x EV-DO system, ATs do not establish or release sessions frequently. After establishing a session, AT may disconnect and resume connection several times during the session. However, certain reasons may initiate a session release. For example, when timer keepalive expires or user originates a release.

The session release flow is very simple. AT and AN exchange a SessionClose message and release the associated resources. PPP session



between AT and PDSN is released simultaneously with the 1x EV-DO session.

Connection Management In 1x EV-DO systems, an open connection between AT and AN refers to AT reverse power control channel, reverse traffic channel allocation, and forward traffic channel (FTC) use. All users having open connections in that sector share FTC in TDM mode. Only after connection set up can AT use high-speed packet data services provided by 1x EV-DO network.

AT Originated Connection Establishment AT and AN can open and close connections several times during a session. Either AT or AN can initiate a connection.

Connection originated by AN supports two modes: Common mode and fast mode. In common mode, AT establishes a connection when it returns a ConnectRequest message after receiving Paging message from AN. In the fast mode, connection is set up after AN sends Channel Assignment message to AT directly. It saves Page/ConnectRequest exchange, speeding up connection setup.

Prior to establishing link with PDSN for the first time, AT passes AN AAA access authentication. After passing authentication successfully, the AT originates link connection with PDSN. After successful authentication, AN AAA returns IMSI to AT. AT uses that IMSI as A10/A11 link identifier and communicates with PDSN.

Figure 28 illustrates AT originated connection establishment flow, where the session between AT and AN already exists before establishing link.



F I G U R E 28 - AT OR I G I N AT E D C O N N E C T I O N E S T AB L I S H M E N T FL O W

Following section describes AT-originated connection establishment flow:

A. AT sends a ConnectRequest message and RouteUpdate message through access channel requesting for connection.

B. After receiving message, AN returns ACAck message through control channel.

C.AN sends TrafficChannelAssignment message containing MAC_ID allocated to AT among other information.

D. After receiving TrafficChannelAssignment message, AT sends Pilot message and DRC message through reverse channel.

E. After receiving pilot and DRC signals from AT, AN sends RTCAck message through FTC to AT.

F. AT returns TarafficChannelComplete message through RTC indicating air link set up.

G. AT notifies AN of data exchange on access stream.

H. AT and AN originate PPP connection and LCP negotiation for access authentication.



I. AN sends CHAP message to AT originating random query, while AT replies with CHAP response.

J. AN collects AT authentication information including Username, CHAP-ID, CHAP-challenge, and CHAP-Response, and sends it to AN AAA through A12 interface.

K. Authentication succeeds, AN AAA returns AccessAccept message.

L. AN sends a CHAP authentication success message to AT.

M. AT originates connection setup with PDSN.

N-Q. AN establishes connection with PDSN through PCF.

R. AT establishes PPP connection with PDSN.

S. AT and PDSN exchange packet data after setting up PPP connection.

AT Originated Connection Release Several reasons can cause Connection release such as timeout of idle timer or AN overload control. Figure 29 illustrates AT-originated connection release flow.

F I G U R E 29 - AT OR I G I N AT E D C O N N E C T I O N R E L E AS E FL O W

Following describes the AT-originated connection release flow:

A. AT sends ConnectClose message through access channel requesting connection release.

B. AN sends A9-Release-A8 message indicating cause value; packet service is dormant to PCF asking PCF to release A8 connection.

C. PCF sends A11-Registration-Request message carrying an activation termination settlement record to PDSN.

D. PDSN returns A11-Registration-Reply message.

E. PCF sends an A9-Release-A8 Complete message to confirm A8 connection release.



Figure 29 illustrates the air link and A8 connection release flow, while it maintains PPP connection between AT and PDSN, and 1x EV-DO session between AT and AN.

Handoff Control In an actual commercial environment, 1x EV-DO and CDMA2000 1x deployment normally takes place simultaneously providing voice services and high-speed packet data services to users. Dual-mode (1x/1x EV-DO) AT can implement handoff between 1x and 1x EV-DO ANs without interrupting PPP connection between AT and PDSN. Voice services take precedence over data services. When transferring data in 1x EV-DO network, AT performs 1x network handoff periodically to listen to the paging channel. On receiving paging for voice call from AN, AT stops data transfer in 1x EV-DO network immediately and begins setting up voice links in 1x network.

Dual-mode AT inter-system handoff scenarios comprise:

Handoff from 1x network to 1x EV-DO network in dormant state

Handoff from 1x EV-DO network to 1x network in dormant state

Handoff from 1x network to 1x EV-DO network in active state

Handoff from 1x EV-DO network to 1x network in active state

Handoff occurs when 1x network receives voice call during data transmission in 1x EV-DO network.

In the event when AT establishes 1x EV-DO session in 1x EV-DO network, the 1x network and 1x EV-DO network share the same PDSN, enabling the network to support concurrent services.

F I G U R E 30 - AT H AN D O F F F R O M 1 X N E T W O R K T O 1 X EV-DO N E T W O R K I N T H E D O R M AN T S T AT E

A~B. AT send DRS=0 message to target AN, target returns Ack order.

C~D. Target AN sets up data channels with PDSN



E. PDSN disconnects with source AN.

This process indicates uninterrupted PPP session between dual-mode AT and PDSN.

Handoff occurs when 1x network receives voice call during data transmission in 1x EV-DO network and is as follows:

F I G U R E 31 - AT H AN D O F F F R O M 1 X EV-DO N E T W O R K T O 1 X N E T W O R K I N T H E D O R M AN T S T AT E

A. AT transits from active state to dormant state.

B. AT in Dormant state performs 1x network to 1xEV-DO1x EV-DO network handoff.

C. In 1xEV-DO1x EV-DO network, AT transits from dormant state to active state.

To avoid missing voice calls originating from 1x network, when the dual-mode AT transfers data in 1xEV-DO1x EV-DO network, it performs handoff to 1x network periodically to listen to the assigned paging timeslots. On receiving voice call paging message, dual-mode AT accesses 1x network to process voice calls due to voice first principle. If 1x network supports concurrent services, it can hand off data session from 1xEV-DO network to 1x network. Packet data transmission continues while performing voice communication.

1x and 1x EV-DO Comparisons Table 10 offers comparisons between 1x EV-DO and 1x.

TAB L E 10 - C O M P AR I S O N S B E T W E E N 1 X EV-DO AN D 1 X

Features 1x 1x EV-DO

Service Voice and data Data

Maximum rate Forward: 307.2 Kb/s (RC3) Reverse: 9.6 Kb/s (RC3)

Forward: 3.1 Mb/s Reverse: 1.8 Mb/s

Channel l i l

CDM in forward and reverse links. Forward: CDM+TDM



Features 1x 1x EV-DO

multiplex Reverse: CDM

Handoff Hard handoff and soft handoff in forward and reverse links

Forward: virtual soft handoff (VHO) Reverse: Soft handoff

Power and rate control

Fast power control in forward and reverse links. No rate control

Reverse: rate control + power control Forward: rate control

Access procedure

Access channel procedure Enhanced access channel procedure

Same as access channel procedure

RF and code features

Convolutional code and Turbo code48-order FIR filter

Turbo code FIR filter is same as that in 1x.

In terms of high-speed data service, 1x EV-DO has the following features compared with CDMA2000 1x technology:

Air interface: 1x EV-DO technology effectively solves data service transmission bottleneck in the air interface.

RF parameters: 1x EV-DO is backward compatible with 1x system.

Technical implementation: 1x EV-DO and CDMA2000 1x adopts the same power control mechanism, soft handoff, access process, and Turbo coding technologies. It enables operators to develop successful 1x EV-DO products easily on the basis of mature CDMA2000 1x development experience.

Networking: 1x EV-DO networking is very flexible. The users who need packet data service only, operators can implement independent networking. It can provide high-speed packet data service with simple network configuration. The core network configuration is an IP based structure rather than the complicated ANSI-41 structure. The users who need voice and data services, operators can implement mixed CDMA2000 1x and CDMA2000 1x EV-DO networking to provide voice service, and high-speed packet data services. In addition, dual-mode AT supports both CDMA2000 1x and 1x EV-DO, technology provides handoff mechanism between CDMA2000 1x and 1x EVDO.


C h a p t e r 6

PTT Technology

This chapter explains: Key PTT technologies.

PTT service flows.

Key PTT Technologies Push-to-Talk (PTT) is one of the most remarkable trunking communication features in communication networks. Trunking communication system is a key mobile communication system branch. However, its application is still restricted to mobile communication.

Channel Sharing An important PTT feature is the forward traffic channel sharing. Channel sharing is the premise of trunking communication. When one person in a group speaks, the other members within the same group are unable to hear at the same time.

CDMA2000 standard optimizes two forward system traffic channels and one reverse traffic channel, enabling forward traffic channel sharing.

Forward Dedicated Control Channel (F-DCCH): Establishment of independent F-DCCH for each user enables transfer of signaling messages and power control information.

Forward Supplemental Channel (F-SCH): Transmits user voice data where F-SCH assignment to each user in the same group has the same long code mask and Walsh code. AT assigned to F-SCH in a group within a particular carrier decodes F-SCH and implements F-SCH sharing. Energy received by each AT is the energy of F-SCHs overlaid in the group within that carrier. Channel sharing is the sharing of channel power and is a standard CDMA feature. Each F-SCH in a group sends the same voice and data packet in the air. All F-SCHs send voice and data in-sync.



Reverse Dedicated Control Channel (R-DCCH): Transmits user signaling messages and reverse voice data. Each activated user in a group has an assigned R-DCCH. Only the terminal that receives authorization information from PDS transfers voice on this channel.

Tip: Chapter 4 describes 1x channels in detail.

Fast Connection Another important PTT service feature is the fast group call and private call connection.

Instead of traditional circuit connection mode, CDMA2000 standard uses data channel to set up fast call connection. Fast call connections reduce channel time as it does not require PPP link establishment on data channel.

In terms of base station processing, CDMA2000 standard implements concurrent processing, which saves access time of users. For called group member, PDS obtains local information of group members from the dispatched database and sends it to PDC, facilitating BSC to page other members in the group quickly.

Although CDMA2000 standard provides no PPP link, Common Trunking Message Link (CTML)/Shared Trunking Data Link (STDL) and F-SCH sharing are standard features of PTT. These features enable group users to remain online permanently.

CTML CTML establishes link during PTT initialization, and transmits PTT call signaling and call control information. Only one CTML connection exists between PDC and PDS. CTML connection remains un-released.

CTML uses A10 connection as bearer channel between PDC and PDS, and uses SDB air link encapsulation. Figure 32 illustrates the process.

F I G U R E 32 - STML TR AN S M I S S I O N L I N K P R O T O C O L

PTT CTML connection signaling categories are: One for message exchange between PDS/PDC and MSs, the other for message exchange between PDS and PDC, and between PDC and BSC.

Chapter 6 - PTT Technology


STDL STDL establishment takes place during PTT call setup. It is responsible for transmitting forward and reverse service data (voice stream) in PTT calls. STDL release takes place in dormant state or at the time of call release. An active group between PDC and PDS corresponds to STDL. All users in a PDC active group coverage area share the same STDL. If distribution of users in an active group takes place in several PDC areas, each PDC establishes STDL with PDS for the activated group.

STDL uses standard A10 connection (GRE) encapsulation. It is the PTT service stream bearer channel. Figure 33 illustrates STDL transmission link protocol.

F I G U R E 33 - STDL TR AN S M I S S I O N L I N K P R O T O C O L

PDC transfers PTT voice stream from MS to PDS. According to group information, PDS distributes PTT voice stream packets received from reverse links to the corresponding forward links.

PTT Service Push-to-Talk (PTT) service is a half-duplex communication mode. It comprises one-to-one and one-to-many dispatch services. One-to-one service refers to private call, and one-to-many service refers to group call. The following section introduces basic PTT service terms.

Group Cal l

A logical set of call members enabling group members to make half-duplex group calls. All members in the same group can hear the voice of any group member.

Group Administrator

The group administrator is a member with special group authority. The group administrator can add, delete, and release activated group members by force.

Group Number

Each applicant group assigned with a group number (GMDN) enables identification of group members when establishing calls.



PTT Dispatched Server (PDS)

The dispatch call center is a PTT standard where PDS can establish calls, and perform location management, user authentication, and service distribution.

PTT Dispatched Cl ient (PDC)

PDC is the equipment that connects with BSS and PDS. It participates in call setup, service duplication, and distribution.

User Pr ior i ty

Setting different priority levels for users defines users with different call authority. The user with higher priority can preempt lower priority user call resources.

Group Call Each group has a unique group number ranging from 4 ~ 6 digits. Any member can originate a group call by pressing group number and pushing PTT key.

A PTT user can belong to several groups at the same time and select the group to establish call session. An idle state user can receive call from any other member of the same group. When the user is active, system prompts a message.

When establishing group call, if MS power is off or not in the PTT service area, call connection does not take place. When the user powers on MS or is in the same service area, the system can add the user to a group call automatically.

When user quits a group call due to an abnormal operation, the system can add the user to the group call again after MS operation restoration.

Users in a group call have the option to quit a group call mid-way and originate another group call or a PSTN call after releasing the PTT key.

Only the dispatch server can release group calls. The group member can choose to quit the group call rather than release the entire group call.

Figure 34 illustrates group call origination flow.



F I G U R E 34 - GR O U P C AL L OR I G I N AT I O N F L O W

A. MS sends an origination message for setting up a group call on the access channel.

B. BSS acknowledges the message on paging channel. If BSS rejects this call because of overload level, it returns an origination reject message to MS and forwards origination message to PDC.

C. PDC sends a message to PDS requesting for establishing a group call.

D. If PDC observes that user has the authority to originate a group call, PDS notifies PDC to set up the call.

E. PDC constructs a service request message and sends it to MSC.

F. MSC assigns terrestrial circuit and sends an assignment request to PDC.

G. BSS sends extended channel assignment message to MS to establish a fundamental channel with MS. This channel enables signal transfer.

H. BSS sends an extended supplemental channel assignment message to establish a supplemental channel with MS. This channel enables service data transfer.

I. PDC sends a message to MSC indicating channel assignment completion.

J. PDC sends a message to PDS indicating active group call connection.

K. PDS sends a message to PDC indicating calling party has authorization to speak.



L. PDC sends a message to the calling MS indicating that the calling party has authorization to speak.

M. MS sends an authorization ACK to PDC.

N. PDC forwards authorization ACK to PDS. The authorized user can speak.

Figure 35 illustrates group call termination flow.

F I G U R E 35 - GR O U P C AL L TE R M I N AT I O N F L O W

A. PDS sends group call paging request to initiate a group call to group members.

B. BSS sends paging request to MS through paging channel.

C. MS responds to the paging request from BSS.

D. PDC constructs a service request message and sends it to MSC.

E. MSC assigns the terrestrial circuit and sends assignment request to PDC.

F. BSS sends an extended channel assignment message to MS to establish a fundamental channel with MS. This channel enables signal transfer.

G. BSS sends an extended supplemental channel assignment message to establish a supplemental channel with MS. This channel enables service data transfer.

H. PDC sends a message to MSC indicating channel assignment completion.

I. PDC sends a message to PDS indicating active group call connection.

Figure 36 illustrates PDS group call origination release flow.



F I G U R E 36 - PDS GR O U P C AL L R E L E AS E OR I G I N AT I O N R E L E AS E FL O W

A. If members of a group do not apply for right to speak within a specified time; the PDS originates group call release to all group members.

B. BSS/PDC sends group call release message to the MS to release air link.

C. BSS/PDC constructs call release request message for each call in the group and sends it to MSC.

D. MSC originates group call release for each call in the group.

E. After releasing air resources and its own resources, BSS/PDC sends a message to MSC indicating group call release completion.

F. After releasing air resource and its own resources, BSS/PDC sends a message to PDS indicating group call release completion.

Figure 37 illustrates group call rejection flow.

F I G U R E 37 - GR O U P C AL L R E J E C T I O N FL O W



A. MS sends group call origination message through access channel.

B. BSS acknowledges the paging channel message. If BSS rejects this call because of overload level, it sends Origination Reject command to MS and forwards the origination message to PDC.

C. PDC sends a message to PDS requesting group call establishment.

D. PDC constructs a service request message and sends it to MSC.

E. If PDS finds that originating user has no right to make a group call, it rejects user request and notifies PDC to reject the call.

F. PDC sends a group call release request.

G. MSC releases group call.

H. BSS/PDC sends group call release message to MS and releases the air link.

I. After releasing air resources and its own resources, BSS/PDC sends a message to MSC indicating successful group release.



Private Call PTT users can dial a short number to make private calls with a group, and dial the complete number to establish a private call with a non-group user.

In a private call, PTT user can push the PTT key and speak after hearing prompt tone instead of waiting for the called party to answer. Following the prompt tone, the called party can hear the voice of the calling party.

User can choose to quit from PTT mode. Under this mode, MS will not receive any paging request for PTT call establishment.

During a private call, both the calling and called parties can terminate the call and use other services such as group call by PTT key release.

If a private call user has other group calls or private calls, system can inform the user using call prompt and display the number of calling party on the MS.

Figure 38 illustrates private call origination flow.

F I G U R E 38 - P R I V AT E C AL L OR I G I N AT I O N F L O W

A. MS sends an origination message for a private call through the access channel.



B. BSS acknowledges the paging channel message. If BSS rejects this call because of overload level, it sends the origination reject command to MS and forwards Origination message to PDC.

C. PDC sends a message to PDS requesting private call establishment.

D. When establishing user call authenticity, PDS informs PDC to set up a private call.

E. PDC constructs a service request message and sends it to MSC.

F. MSC assigns terrestrial circuit requested and sends an assignment request to PDC.

G. BSS sends an extended channel assignment message to MS to establish a fundamental channel with MS. This channel enables signal and service data transmission.

H. PDC sends a message to MSC indicating channel assignment completion.

I. PDC sends a message to PDS indicating active private call connection.

J. PDS sends a message to PDC indicating authorization of calling party to speak.

K. PDC sends a message to the calling MS indicating authorization of calling party to speak.

L. MS sends authorization ACK to PDC.

M. PDC forwards authorization ACK to PDS indicating that authorized user can speak.

Figure 39 illustrates private call termination flow.

F I G U R E 39 - P R I V AT E C AL L TE R M I N AT I O N FL O W

A. PDS originates paging request for private call.

B. BSS sends paging request to MS through paging channel.



C. MS responds to the paging request from BSS.

D. BSC constructs service request message and sends it to MSC.

E. MSC assigns the terrestrial circuit requested and sends an assignment request to PDC.

F. BSS sends an extended channel assignment message to MS to establish a fundamental channel with MS. This channel enables signaling and service data transmission.

G. PDC sends a message to MSC indicating channel assignment completion.

H. PDC sends a message to PDS indicating call setup completion.

Note: Private call release is similar to group call release. See Figure 39 section for details.

Management of Talk Rights Talk right is the premise of PTT conversation. After PTT terminal call origination and connection, the conversation does not begin unless PDS authorizes the terminal with talk right.

Figure 40 illustrates application flow for talk rights management.

F I G U R E 40 - TAL K R I G H T AP P L I C AT I O N FL O W

A. User A pushes MS1 PTT key initiating the talk right application request.

B. BSS/PDC forwards MS1 talk right application request to PDS.

C. User B pushes MS2 PTT key initiating talk right application request.



D. BSS/PDC forwards MS2 talk right application request to PDS.

E. Based on the talk right algorithm, PDS determines MS1 authorize talk right.

F. BSS/PDC forwards talk right authorization message to MS1.

G. PDS rejects talk right application request from MS2 based on talk right decision algorithm.

H. BSS/PDC forwards talk right request rejection message to MS2.

I. MS1 returns talk right authorization ACK message to BSS/PDC.

J. BSS/PDC forwards talk right authorization ACK message to PDS.

Figure 41 illustrates MS originated talk right release.

F I G U R E 41 – MS OR I G I N AT E D TAL K R I G H T R E L E AS E FL O W

A. User with talk right or waiting for talk right releases PTT key initiating request for talk right release.

B. BSS/PDC forwards talk right release request from MS to PDS and starts Tpttrelease timer and at the same time waits for request acknowledgement.

C. PDS releases talk right and returns talk right release ACK message to BSS/PDC.

D. BSS/PDC forwards talk right release ACK message to MS and disables Tpttrelease timer at the same time.

Figure 42 illustrates PDS talk right release flow.



F I G U R E 42 - PDS TAL K R I G H T R E L E AS E FL O W

MS BSS/PDC PDS

Talk right release request

Talk right release request

Talk right release ACK

Talk right release ACK

A

D

C

B

A. If user with talk right exceeds talk time limit, PDS sends talk right release request.

B. BSS/PDC forwards talk right release request from PDS to MS.

C. MS releases talk right and sends talk right release ACK message to BSS/PDC.

D. BSS/PDC forwards talk right release ACK message to PDS.





Abbreviations

Abbreviation Meaning

3GPP2 3rd Generation Partnership Project 2

AMPS Advanced Mobile Phone System

AN Access Network

ANSI American National Standards Institute

AT Access Terminal

ATM Asynchronous Transfer Mode

BER Bit Error Rate

BSMAP Base Station Module Administrator Part

BSS Base Station System

CCCH Common Control Channel

CDMA Code Division Multiple Access

CELP Code Excited Linear Prediction

CPCCH Common Power Control Channel

CPCH Common Packet Channel

CPICH Common Pilot Channel

CRC Cyclic Redundancy Check

CWTS China Wireless Telecommunications Standard Group

DCCH Dedicated Control Channel

DRC Data Rate Control

DSCH Dedicated Signaling Channel

DSSS Direct Sequence Spread Spectrum

DTAP Direct Transfer Part

DTMF Dual Tone Multi-Frequency EV-DO Evolution-Data Optimized/Only

EV-DV Evolution-Data & Voice

F-BCCH Forward Broadcast Control Channel

F-CACH Forward Common Assignment Channel

F-CCCH Forward Common Control Channel




F-CPCCH Forward Common Power Control Channel

F-DCCH Forward Dedicated Control Channel

FDMA Frequency Division Multiple Access FHSS Frequency Hopping Spread Spectrum

F-FCH Forward Fundamental Channel

F-PCH Forward Paging Channel

F-PCSCH Forward Power Control Sub-channel

F-PDCCH Forward Packet Data Control Channel

F-PDCH Forward Packet Data Channel

F-PICH Forward Pilot Channel

FPLMTS Future Public Land Mobile Telecommunication System

F-QPCH Forward Quick Paging Channel

F-SCCH Forward Supplemental Code Channel

F-SCH Forward Supplemental Channel

F-SYNCH Forward Sync Channel

F-TCH Forward Traffic Channel

F-TDPICH Forward Transmit Diversity Pilot Channel

GPS Global Positioning System

GSM Global System for Mobile Communications

HLR Home Location Register

ITU International Telecommunications Union

MAC Medium Access Control

MS Mobile Station

MSC Mobile Switching Center

MSRG Modular Sequence Random Generator

MWI Message Wait Indication

NMTS Nordic Mobile Telephone System

PCF Packet Control Function

PCM Pulse Code Modem

PCT Power Control Threshold

PDSN Packet Data Service Node

PDC PTT Dispatched Client

PDS PTT Dispatched Server

PER Packet Error Rate

PHS Personal Handset System




PN Pseudo Number

PSTN Public Switched Telephone Network

PTT Push-To-Talk

QPSK Quadrature Phase Shift Keying

RA Reverse Active

RAB Reverse Active Bit

R-ACH Reverse Access Channel

RC Radio Configuration

R-CCCH Reverse Common Control Channel

R-DCCH Reverse Dedicated Control Channel

R-EAAH Reverse Enhanced Access Channel

RPC Reverse Power Control

R-PICH Reverse Pilot Channel

R-SCCH Reverse Supplemental Code Channel

R-SCH Reverse Supplemental Channel

R-TCH Reverse Traffic Channel

RTT Radio Transmit Technology

SCCP Signaling Connection and Control Part

STDL Shared Trunking Data Link

SSRG Simple Sequence Random Generator

TACS Total Access Communication System

TDD Time Division Duplex

TDM Time Division Multiplexing

TDMA Time Division Multiple Access

THSS Time Hopping Spread Spectrum

TIA Telecommunications Industries Association

UATI Unicast Access Terminal Identifier

UMTS Universal Mobile Telecommunications System

VHO Virtual Handoff





Figures

Figure 1 - CDMA2000 Technology Standards ..................................................16 Figure 2 - Spreading and De-spreading Process ..............................................18 Figure 3 - CDMA Spread Spectrum Communication Principles ...........................21 Figure 4 - Signal Waveform During Spreading and De-spreading.......................22 Figure 5 - Frequency Reuse in FDMA and TDMA..............................................27 Figure 6 - CDMA Frequency Reuse ................................................................28 Figure 7 - Delay Difference Between BSs .......................................................37 Figure 8 - Search Window and Pilot Signal .....................................................37 Figure 9 - Soft Handoff Flow ........................................................................39 Figure 10 - CDMA2000 1x Forward Channels..................................................42 Figure 11 - CDMA2000 1x Reverse Channels ..................................................43 Figure 12 - MOC Flow .................................................................................46 Figure 13 - MTC Flow..................................................................................48 Figure 14 - MS Originated Release Flow.........................................................49 Figure 15 - BSS Originated Release Flow .......................................................50 Figure 16 - MSC Originated Call Release Flow.................................................51 Figure 17 - MS Originated Data Service Call Flow............................................52 Figure 18 - MS Originated Call Release Flow...................................................54 Figure 19 - PDSN Inter-PCF Dormant Handoff ................................................55 Figure 20 - PDSN Inter-PCF Active Handoff ....................................................57 Figure 21 - CDMA2000 1x EV-DO NETWORK MODEL (Revision 0) ......................60 Figure 22 - CDMA2000 1x EV-DO Network Model (Revision A) ..........................60 Figure 23 – 2000 1x and 1x EV-DO Spectrum Features....................................61 Figure 24 - CDMA2000 1x EV-DO Forward Channels........................................62 Figure 25 - CDMA2000 1x EV-DO Reverse Channels ........................................63 Figure 26 - UATI Assignment Flow ................................................................67 Figure 27 - Session Negotiation Flow ............................................................68 Figure 28 - AT Originated Connection Establishment Flow ................................70 Figure 29 - AT Originated Connection Release Flow .........................................71 Figure 30 - AT Handoff from 1x network to 1x EV-DO Network In the dormant

State ................................................................................................72 Figure 31 - AT Handoff from 1x EV-DO network to 1x network in the dormant state

........................................................................................................73 Figure 40 - STML Transmission Link Protocol ..................................................76 Figure 41 - STDL Transmission Link Protocol ..................................................77 Figure 42 - Group Call Origination flow..........................................................79 Figure 43 - Group Call Termination flow ........................................................80 Figure 44 - PDS Group Call Release Origination Release Flow............................81 Figure 45 - Group Call Rejection Flow............................................................81 Figure 46 - Private Call Origination flow.........................................................83 Figure 47 - Private Call Termination Flow.......................................................84 Figure 48 - Talk Right Application Flow..........................................................85 Figure 49 – MS Originated Talk Right Release Flow .........................................86 Figure 50 - PDS Talk Right Release Flow........................................................87





Tables

Table 1 - Typographical Conventions..............................................................ix Table 2 - Mouse Operation Conventions.......................................................... x Table 3 - Safety Signs .................................................................................xi Table 4 - Air Interface Parameters of CDMA2000 1x System.............................42 Table 5 - Functions and Features of CDMA2000 1x Forward Channels ................43 Table 6 - Functions and Features of CDMA2000 1x Reverse Channels ................44 Table 7 - Data Service Requirements ............................................................60 Table 8 - Functions and Features of CDMA2000 1x EV-DO Forward Channels ......62 Table 9 - Functions and Features of CDMA2000 1x EV-DO Reverse Channels ......64 Table 10 - Comparisons Between 1x EV-DO and 1x.........................................73





Index

AAA .................. 54, 57, 59 ACK .......... 52, 68, 72, 74, 75 AN .. 49, 50, 51, 52, 53, 54, 55,

56, 57, 58, 59, 60, 61, 77 ANSI .................. 3, 62, 77 AT 25, 49, 50, 51, 52, 53, 54,

55, 56, 57, 58, 59, 60, 61, 62, 63, 77, 81

ATM .......................... 77 B 5, 21, 31, 34, 36, 37, 38, 39,

40, 42, 43, 46, 55, 56, 58, 59, 60, 61, 67, 68, 69, 70, 72, 73, 74, 75

Backward open-loop power control.................... 17

Backward outer-loop power control.................... 18

bandwidth .................... 17 BS ... 34, 35, 37, 40, 41, 44, 46 BSC .......... 24, 41, 54, 64, 73 BSS ............................

.. 29, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 66, 67, 68, 69, 70, 72, 73, 74, 75, 77, 81

BSSB .......... 1, ii, iii, ix, 4 BTS .............. 17, 18, 24, 53 CAPS ......................... ix CDMAv, vi, 1, 2, 3, 5, 8, 9, 10,

11, 12, 15, 16, 17, 18, 20, 21, 24, 29, 33, 47, 63, 77, 81

CDMA2000 .......................1, iii, v, vi, 1, 3, 4, 9, 12, 16, 17, 29, 30, 31, 32, 33, 39, 47, 48, 49, 50, 51, 52, 60, 62, 63, 64, 81, 83

channel .................. 17, 18 CRC ...................... 12, 77 DC 1, 64, 65, 67, 68, 69, 70, 72,

73, 74, 75 DRC .......... 50, 52, 53, 58, 77 DROP ..................... 26, 27 DV 77 E 1, iii, 23, 32, 35, 37, 38,

40, 42, 44, 46, 55, 58, 59, 61, 63, 64, 65, 66, 67, 68, 69, 70, 72, 73, 74, 88

EACH ......................... 32 ETSI ....................... 2, 3 EV .. vi, vii, 4, 18, 47, 48, 49,

50, 51, 52, 53, 54, 56, 57, 60, 61, 62, 77, 81, 83

EVDO ........................ 62 EV-DOvi, vii, 4, 18, 47, 48, 49,

50, 51, 52, 53, 54, 56, 57, 60, 61, 62

EV-DO ....................... 77 EV-DO ....................... 81 EV-DO ....................... 81 EV-DO ....................... 81 EV-DO ....................... 81 EV-DO ....................... 81 EV-DO ....................... 81 EV-DO ....................... 81 EV-DO ....................... 83 EV-DO ....................... 83 EV-DO ....................... 83 FA .......................... 33 FCH ..................... 19, 78 FER ......................... 19 F-PCH ................... 31, 78 F-QPCH .................. 31, 78 frame ratio ................. 18 F-SCH ............... 63, 64, 78 F-SYNCH ..................... 78 GoTa ................ 63, 64, 66 GPS ...................... 3, 78 HLR ......................... 78 INFORMATION ................. ii IP .......... 29, 33, 41, 54, 62 IS C ................. 52, 58, 78 MODEL ................... 48, 81 MS . 16, 17, 18, 19, 20, 21, 23,

24, 25, 26, 27, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 78, 81

MSC ............................ 27, 34, 35, 36, 37, 38, 39, 40, 41, 42, 44, 46, 67, 68, 69, 70, 72, 73, 78, 81

N/A ........................ iii NETWORK ................. 48, 81 P 1, iii, vii, 1, 33, 37, 41,

42, 43, 44, 45, 46, 54, 57, 59, 60, 61, 64, 65, 66, 67, 68, 69, 70, 72, 73, 74, 75, 78, 81, 88

PCF ............................ 33, 41, 42, 43, 44, 45, 46, 47, 59, 78, 81

PCT ......................... 78



PDS .............................. 64, 65, 66, 67, 68, 69, 70, 72, 73, 74, 75, 78, 81

PDSN ............................. 33, 41, 42, 43, 44, 45, 46, 54, 57, 59, 60, 61, 78, 81

PER .......................... 78 PPP . 39, 41, 56, 58, 59, 60, 61,

64 PTT vii, 33, 63, 64, 65, 66, 71,

73, 74, 78, 79 R&D ......................... iii R1 ...................... ii, iii R-ACH .................... 32, 79 RAKE ................. vi, 23, 24 response time ................ 17

RF .............. 32, 47, 54, 62 RPC ..................... 50, 79 R-SCH ....................... 79 RTT ................ v, 3, 4, 79 SCCP ................ 38, 39, 79 SCH ......... 19, 63, 64, 78, 79 shadow effect ............... 17 SNR ........... 5, 7, 17, 18, 52 SOFT ........................ 27 SYNC ........................ 31 TD-SCDMA ..................... 3 transmitting power .......... 17 URL ...................... 1, 88 V 46 WCDMA ........................ 3 ZXC10 ........ 1, ii, iii, ix, 4

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