PROFESSIONAL
`
`I
`
`General Packet Radio Service
`
`Putting the pieces of GPRS together -
`using hundreds of diagrams
`
`Overlaying data on existing cellular networks
`
`Mobile user market drivers
`
`GPRS interaction with IP, X.25, and Frame Relay
`
`GPRS and VPNs
`
`REGIS J. 11BUD" BATES
`
`Samsung, Exh. 1003, p. 1
`
`

`
`Samsung, Exh. 1003, p. 2
`
`E£
`
`“F
`
`4 ?
`
`Samsung, Exh. 1003, p. 2
`
`

`
`GPRS
`
`((3%;-:11er21} §Packet
`Ra.<jl:'i_o Ezkxrvtice)
`
`Samsung, Exh. 1003, p. 3
`
`Samsung, Exh. 1003, p. 3
`
`

`
`MCGRAW-HILL
`TELECOMMUNICATIONS
`
`Bates Broadband Telecommunications Handbook
`Bates Optical Switching and Networking Handbook
`Bates Wireless Broadband Handbook
`Bates GPRS
`
`Samsung, Exh. 1003, p. 4
`
`

`
`GPRS
`
`Regis J. (Bud) Bates
`
`McGraw-Hill
`New York Chicago San Francisco Lisbon
`London Madrid Mexico City Milan New Delhi
`San Juan Seoul Singapore Sydney Toronto
`
`Samsung, Exh. 1003, p. 5
`
`

`
`McGraw-Hill
`~
`A Division ofTheMcGraw·HillCompanies
`
`Copyright© 2002 by The McGraw-Hill Companies, Inc. All rights reserved.
`Printed in the United States of America. Except as permitted under the United
`States Copyright Act of 1976, no part of this publication may be reproduced or
`distributed in any form or by any means, or stored in a data !base or retrieval
`system, without the prior written permission of the publisher.
`1 2 3 4 5 6 7 8 9 0 AGM/AGM 9 8 7 6 5 4 3 2 1
`
`ISBN 0-07-138188-0
`
`The sponsoring editor for this book was Steve Chapman and the production
`supervisor was Pamela Pelton. It was set in Century Schoolbook by MacAllister
`Publishing Services, LLC.
`
`Printed and bound by Quebecor/Martinsburg.
`
`Throughout this book, trademarked names are used. Rather than put a trademark
`symbol after every occurrence of a trademarked name, we use names in an editorial
`fashion only, and to the benefit of the trademark owner, with no intention of infringe(cid:173)
`ment of the trademark. Where such designations appear in this book, they have been
`printed with initial caps.
`
`Information contained in this work has been obtained by The McGraw-Hill
`Companies, Inc. ("McGraw-Hill") from sources believed to be reliable. However,
`neither McGraw-Hill nor its authors guarantees the accuracy or completeness
`of any information published herein and neither McGraw-Hill nor its authors
`shall be responsible for any errors, omissions, or damages arising out of use of
`this information. This work is published with the understanding that McGraw(cid:173)
`Hill and its authors are supplying information but are not attempting to ren(cid:173)
`der engineering or other professional services. If such services are required, the
`assistance of an appropriate professional should be sought.
`
`0
`
`This book is printed on recycled, acid-free paper containing a minimum of
`50 percent recycled de-inked fiber.
`
`Samsung, Exh. 1003, p. 6
`
`

`
`-
`
`-
`
`ABOUT THE AUTHOR -
`Regis J. (Bud) Bates Jr., President
`TC International Consulting, Inc.
`Phoenix, Arizona
`1-800-322-2202
`
`-
`
`-
`
`Regis (Bud) Bates has more than 35 years of experience in telecommuni(cid:173)
`cations and management information systems (MIS). He oversees the
`operation of TC International Consulting, Inc., a full service management
`consulting organization. He has been involved in the design of major net(cid:173)
`works including LANs and WANs. His clients span the range of Fortune
`100-500 companies. Many of his projects deal with multiple sites and
`countries using Frame Relay, ATM, and Optical architectures. He has also
`done a significant amount of work in the wireless communications area.
`Bud also develops and conducts various public and in-house seminars
`ranging from a managerial overview to very technical instruction on
`voice, data, LAN, WAN, and broadband communications. For the past two
`years, he has devoted much of his development and training activities on
`the convergence of voice and data communications. Included in these
`developments, Bud has been training numerous CLECs on the integra(cid:173)
`tion of voice and data. He has recommended and implemented several
`training programs (in-house) using all the technologies that are converg(cid:173)
`ing as a base model. Included in this list are several training programs
`that carry the organization's internal certification. His many topics
`include both basic and advanced courseware on voice, data, LAN, WAN,
`ATM, SONET, Tl/T3, VoIP, and Voice over Data Protocols (FR, ATM, and
`so on).
`
`Samsung, Exh. 1003, p. 7
`
`

`
`vi
`
`About the Author
`
`Bud has written numerous books on the technologies, many of which
`have been best sellers for McGraw-Hill. Moreover, his Voice and Data
`Communications Handbook has led McGraw-Hill's sales for three con(cid:173)
`secutive years, with a new revision released in August 2001. His recent
`publication Broadband Telecommunications Handbook (December 1999)
`has been an equal seller. Some of his other titles include, Introduction to
`Tl IT3 Networking; Disaster Recovery for LANs: A Planning and Action
`Guide; Telecommunications Disaster Recover; Wireless Networked Com(cid:173)
`munications: Concepts, Systems, and Implementation; Optical Switching
`and Networking; Nortel Networks Layer 3 Switching; and Wireless Broad(cid:173)
`band Handbook.
`Bud also works with venture capitalists for various analyses and stud(cid:173)
`ies. One of his recommendations got the investors to increase the recom(cid:173)
`mended funding from $100 million to more than $400 million. He has
`consistently been on the mark with his projections.
`
`Samsung, Exh. 1003, p. 8
`
`

`
`-
`
`CONTENTS
`
`Chapter 1
`
`Introduction to GSM
`
`Objectives
`History of Cellular Mobile Radio and GSM
`Benchmarks in GSM
`~M~~G
`Cell Structure
`Types of Cells
`Macrocells
`Microcells
`Selective Cells or Sectorized Cells
`Tiered Cells
`Umbrella Cells
`Analog to Digital Movement
`TeleseNices
`Bearer SeNices
`Supplementary SeNices
`GSM Architecture
`Mobile Equipment or Mobile Station
`Subscriber Identity Module
`The Mobile Station Function
`The Base Transceiver Station (BTS)
`The Base Station Controller (BSC)
`Base Station Subsystem
`The Transcoder and Adaptation Unit (TRAU)
`Locating the TRAU
`Mobile Switching Center
`The Registers Completing the NSS
`The Cell
`Location Area
`MSCNLR SeNice Area
`Public Land Mobile Network (PLMN)
`OSI Model-How GSM Signaling Functions in the OSI Model
`Layer Functionality
`Mobile Station Protocols
`The Mobile Station to BTS Protocols
`BSC Protocols
`MSC Protocols
`
`2
`2
`3
`5
`5
`8
`8
`9
`1 0
`1 O
`1 O
`1 2
`13
`1 3
`I 4
`1 6
`1 7
`18
`1 8
`19
`20
`2 I
`22
`22
`22
`24
`26
`26
`26
`26
`27
`28
`29
`30
`30
`31
`
`Samsung, Exh. 1003, p. 9
`
`

`
`viii
`
`Contents
`
`Defining the Channels
`Frequencies Allocated
`Primary GSM
`Radio Assignment
`Frequency Pairing
`Extended GSM Radio Frequencies
`Modulation
`Amplitude Shift Keying (ASK)
`Frequency Shift Keying (FSK)
`Phase Shift Keying (PSK)
`Gaussian Minimum Shift Keying (GMSK)
`Access Methods
`FDMA
`TOMA
`CDMA
`TOMA Frames
`Time Slot Use
`GSM FDMA!TDMA Combination
`Logical Channels
`The Physical Layer
`Speech Coding on the Radio Link
`Channel Coding
`Convolutional Coding
`
`Chapter 2
`
`GPRS Introduction
`
`Objectives
`Introduction to the Internet and Wireless Wave
`The New Wave of Internet User
`General Packet Radio Service (GPRS)
`The GPRS Story
`What Is GPRS?
`Market Timeline for GPRS
`Motivation for GPRS
`Evolution of Wireless Data
`Wireless Data Technology Options
`GPRS Roaming
`The GSM Phase II Overlay Network
`Circuit-Switched or Packet-Switched Traffic
`GPRS Radio Technologies
`Cells and Routing Areas
`
`31
`32
`32
`34
`34
`34
`35
`35
`36
`36
`37
`38
`39
`39
`40
`42
`42
`42
`43
`43
`44
`45
`45
`
`47
`
`48
`48
`50
`52
`53
`54
`57
`57
`58
`59
`61
`62
`63
`65
`66
`
`Samsung, Exh. 1003, p. 10
`
`

`
`Contents
`
`Attaching to the Serving GPRS Support Node
`Packet Data Protocol (PDP) Contexts
`Data Transfer
`GSM and NA-TDMA Evolution
`GPRS Terminals
`Mobile Station Classes for Multislot Capabilities
`Applications for GPRS
`Chat
`Textual and Visual Information
`Still Images
`Moving Images
`Web Browsing
`Document Sharing/Collaborative Working
`Audio
`Job Dispatch
`Corporate E-mail
`Internet E-mail
`Vehicle Positioning
`Remote LAN Access
`File Transfer
`Home Automation
`
`Chapter 3
`
`System Architecture
`
`Objectives
`Network Architecture
`GPRS Subscriber Terminals
`GPRS BSS
`GPRS Network
`Databases (VLR and HLR)
`Data Routing
`Data Packet Routing
`GPRS Mobility Management
`Network Architecture-New Interfaces
`The Different Backbones Used
`Initial Implementations
`TDMA-GPRS Physical Channel Capacity
`GPRS Logical Channels
`Packet Broadcast Control Channel (PBCCH)
`Packet Common Control Channel (PCCCH)
`Packet Data Traffic Channel (PDTCH)
`
`67
`68
`69
`71
`71
`72
`74
`74
`74
`75
`75
`76
`76
`76
`77
`77
`78
`78
`78
`79
`79
`
`81
`
`82
`82
`83
`83
`84
`85
`86
`86
`88
`90
`91
`92
`93
`94
`94
`94
`95
`
`Samsung, Exh. 1003, p. 11
`
`

`
`x
`
`Contents
`
`Packet-Dedicated Control Channel (PDCCHJ
`Mapping Logical Channels onto Physical Channels
`
`Chapter 4
`
`Function of GPRS Elements
`
`Objectives
`Impact on the Base Station Subsystem (BSS)
`The Packet Control Unit Support Node (PCUSN)
`Channel Codec Unit (CCU)
`Data Link Layer-Layer 2
`lAPD Data Link Layer
`Impact on BSC: A New lAPD
`Agprs OML BSC-PCU
`Agprs GSL BTS-PCU (Through the BSC)
`Agprs RSL BSC-PCU
`Function of the PCUSN
`Serving GPRS Support Node (SGSN) Functions
`
`Gateway GPRS Support Node fGGSN)
`Home Location Register (HLR)
`The Visitor Location Register (VLR)
`Other Network Elements
`SS? /IP Gateway Functions
`Domain Name System (DNS)
`Figuring Out Which Server Knows What
`Domain Name Space
`DNS and lnter-PLMN Network
`Dynamic Host Configuration Protocol f DHCP)
`How the Protocol Works (Basic)
`Charging Gateway Function
`The Operations and Maintenance Center f OMC)
`and the Network Management Center (NMC)
`OMC Communication GPRS Domain Managers
`PCUSN OAM Server
`OMC-D Architecture
`
`Chapter 5 Main GPRS Procedures
`
`Objectives
`Mobility Management (MM)
`GPRS Attach
`GPRS Attach Scenario
`
`96
`96
`
`99
`
`100
`IOI
`102
`103
`104
`104
`105
`106
`106
`106
`107
`108
`J 10
`111
`112
`113
`114
`116
`119
`120
`122
`122
`123
`124
`
`126
`127
`127
`128
`
`131
`
`132
`132
`134
`135
`
`Samsung, Exh. 1003, p. 12
`
`

`
`Contents
`
`Mobile Station-Initiated GPRS Detach
`Detach Type-GPRS-Only, IMSl-Only, or Combined
`Network-Initiated GPRS Detach
`Activating a PDP Context for Packet Routing and Transfer
`GPRS Context Activation-Scenario
`Mobile-Initiated PDP Data Protocol Context Activation
`Network-Initiated Packet Data Protocol Context Activation
`GPRS Data Transfer from the Mobile Station
`GPRS Data Transfer to the Mobile
`Mobile-Initiated Packet Data Protocol Context Deactivation
`Network-Initiated Packet Data Protocol Context Deactivation
`Security Functions
`Authentication
`Ciphering
`Web Access
`
`Chapter 6 Radio and MS-PCUSN Interfaces
`
`Objectives
`Radio Link Control/Medium Access Control and
`Radio Frequency Layers
`Packet Logical Channels
`Packet Logical Channels-POCH Allocation
`Packet Logical Channels-Multiframe Structure
`Packet Broadcast Control Channel (PBCCH)
`System Information Type 13 (SJ 13)
`SI 13 Message Contains One of the Two Indications
`Network Control
`How the Mobile Knows the POCH Configuration
`Example of PBCCH I PCCCH Configuration
`Packet Traffic Channels
`One-Phase and Two-Phase Access
`Packet Uplink Assignment
`Access Request
`Access Answer
`Resource Request
`Resource Assignment
`Static Uplink (UL) Allocation
`Temporary Block Flow
`Dynamic Uplink (UL) Allocation
`
`137
`137
`I 38
`I 39
`140
`14 I
`I 44
`145
`146
`I 48
`148
`149
`I 50
`I 5 I
`I 5 I
`
`153
`
`154
`
`154
`155
`161
`162
`164
`165
`165
`166
`167
`169
`170
`172
`173
`174
`174
`175
`175
`176
`177
`179
`
`Samsung, Exh. 1003, p. 13
`
`

`
`Xii
`
`Contents
`
`Temporary Block Flow (TBF) for Dynamic Allocation
`RLC/MAC Block Structure
`Temporary Block Flow-Uplink (UL) Data Transfer
`Downlink (DL) Resource Allocation
`Timing Advance Updating Procedure
`Initial Timing Advance Estimation (During Access Phase)
`Continuous Update Procedure (During Transfer State)
`Identifiers Limitations
`The Temporary Flow Identifier
`The Timing Advance Index
`The Uplink State Flag
`RLC/MAC Block
`Activity at the BSS
`Medium Access Control (MAC) Layer
`Key Identifiers for the MAC Layer
`Channel Allocation and the MAC Layer
`The MAC Header
`Radio Link Control (RLC) Layer
`Mobile-Originated Access Message Sequence
`The Radio Resource [RR) State Model
`BSS GPRS Protocol (BSSGP) Layer
`Channel Coding
`Interleaving Speech Channels
`Interleaving For the GSM Data TCH Channels
`Channel Coding in GPRS
`Coding Scheme- I (CS- I)
`Coding Scheme-2 (CS-2)
`Coding Scheme-3 (CS-3)
`Coding Scheme-4 (CS-4)
`Normal Burst
`Access Burst
`RLC Layer Segmentation
`Quality of Service (QoS)
`
`Chapter 7
`
`X.25, lnternets, lntranets, and Extranets
`
`Objectives
`Modes of Switching
`Circuit Switching
`Packet Switching Defined
`The Packet Concept
`
`I 79
`180
`I 82
`183
`184
`186
`186
`187
`187
`187
`188
`I 88
`I 89
`189
`190
`I 92
`192
`I 94
`194
`I 96
`197
`I 98
`200
`200
`20 I
`203
`203
`204
`204
`205
`206
`206
`207
`
`209
`
`210
`210
`210
`211
`212
`
`Samsung, Exh. 1003, p. 14
`
`

`
`Contents
`
`xiii
`
`Overhead
`The Packet Network
`The User Connection
`Benefits of Packets
`Other Benefits
`Advantages of Packet Switching
`Other Components of Packet Switching
`Other Forms of Packet
`The internet
`Protocols and Technologies Enabled the Internet
`What Then Is the Internet?
`lntranets
`Extra net
`The World Wide Web
`Transmission Control Protocol/Internet Protocol (TCP/IP)
`Internet Protocols (IPs)
`TCP
`Address Resolution Protocols (ARPs)
`IP Addressing
`IP Subnetworking and Masking
`Internet Routing
`ICMP
`IRDP
`Transport Layer
`Transmission Control Protocol (TCP)
`TCP Segment Format
`User Datagram Protocol (UDP)
`Upper-Layer Protocols
`The IP Header
`Implementing Extranets
`TCP Filtering
`
`Chapter 8 Mobile Station to SGSN Interface
`
`Objectives
`Logical Link Control (LLC) Layer
`What LLC Does
`Subnetwork-Dependent Convergence Protocol [SNDCP)
`GPRS Mobility Management/Session Management
`(GMM/SM)
`Short Message Service [SMS)
`
`2 J 2
`2 J 4
`2 J 5
`2 J 9
`2 I 9
`221
`222
`223
`225
`226
`226
`228
`229
`229
`230
`232
`234
`235
`237
`238
`239
`241
`241
`242
`242
`242
`243
`243
`244
`246
`246
`
`249
`
`250
`250
`2 5 1
`251
`
`252
`252
`
`Samsung, Exh. 1003, p. 15
`
`

`
`xiv
`
`Contents
`
`LLC Support
`LLC Service Access Point Identifiers (SAPls)
`LLC Identifiers
`LLC Layer Structure
`Mapping the LLC Frame
`GPRS Ciphering Environment
`Authentication
`Ciphering
`GPRS Mobility Management (GMM)
`Temporary Logical Link Identifier (TLLI)
`How the TLLI Is Used
`How the TLLI Is Transmitted
`Mobility Management (MM)
`GPRS Attach Procedure
`Cell Update in Packet Idle Mode
`Cell Update in the Packet Transfer Mode
`Routing Area Updates (lntra-SGSN)
`RA Updates (lnter-SGSN)
`SNDCP Layer
`SNDCP Identities
`SNDCP Service Functions
`SNDCP Layer-NSAPls
`SNDCP Compression and Segmentation
`
`Chapter 9
`
`PCUSN-to-SGSN Interface f Gb)
`
`Objectives
`High-Level Characteristics of the Gb Interface
`Position of BSSGP Within the Protocol Stack
`on the Gb Interface
`The Protocol Stack for Gb Interface
`Frame Relay Networks
`The FRAD
`The Protocol Data Unit (POU)
`Frame Relaying
`Benefits of Frame Relay
`Service Comparison
`Why Frame Relay Was Developed
`The Significance of Frame Relay
`The Basic Data Flow
`Data Link Connection Flow
`
`252
`253
`254
`254
`256
`257
`257
`257
`259
`260
`261
`262
`263
`263
`264
`265
`265
`266
`267
`268
`269
`270
`271
`
`275
`
`276
`276
`
`276
`277
`278
`278
`279
`280
`281
`282
`282
`284
`286
`288
`
`Samsung, Exh. 1003, p. 16
`
`

`
`Contents
`
`The FECN and BECN
`Frame Relay Speeds
`Provisioning PVCs and SVCs
`SVC UN/s and NN/s
`The Network-to-Network Interface (NNI)
`Frame Relay/ATM Interworking
`Network Service Sub/ayers
`Identifiers Managed by the NS Layer
`Network Service Control Procedures
`BSSGP Identifiers
`PDU Transmission
`BSSGP Virtual Connection Identifier (BVCI)
`Flow Control Procedures
`Mode of Operation
`Control of the Downlink Throughput by the SGSN
`
`Chapter 10 SGSN-to-GGSN (Gn) and GGSN-to-PDN (G;) Interface
`
`Objectives
`GPRS Tunneling Protocol (GTP)
`GTP Messages
`GPRS Tunneling Protocol (GTP) Layer
`GTP Identities
`Virtual Private Networks (VPNs)
`Authentication
`Security
`Roaming and Wireless VPNs
`What Makes GPRS VPNs Different?
`VPN-Service Provider Independent (SPI)
`VPN-IPSec End-to-End with PKI
`VPN-Service Provider Dependent (SPD)
`L2TP-Based Wireless VPN in a GPRS Infrastructure
`IPSec Gateways and Compulsory Tunneling W-VPN
`Multiple VPN Gateway Architecture
`Using the VPN Tunnel
`PDP Context SGSN Role
`Create PDP Context GGSN Role
`What Is a Directory?
`Transparent Access
`Transparent Mode
`Nontransparent Access
`
`289
`290
`292
`292
`292
`293
`294
`296
`297
`297
`298
`299
`300
`301
`301
`
`303
`
`304
`304
`306
`307
`308
`309
`312
`313
`315
`316
`316
`318
`319
`319
`321
`322
`323
`325
`326
`327
`328
`329
`330
`
`Samsung, Exh. 1003, p. 17
`
`

`
`Nontransparent Mode
`Virtual Dial-Up (Enhanced Nontransparent)
`
`Chapter 11 Future Enhancements and Services
`
`Objectives
`Mobile Evolution
`First Generation (I G)
`Second Generation (2G)
`Third Generation (3G)
`HSCSD
`Two Time Slots
`Enhanced General Packet Radio Service (E-GPRS)
`Enhanced Data Rates for GSM Evolution (EDGE)
`What Is Special about EDGE?
`The Third Generation
`UMTS Terrestrial Radio Access Network (UTRAN)
`Multimode Second-Generation/UMTS Terminals
`Open Interfaces
`UTRAN Architecture
`Node B
`Radio Network Controller (RNC)
`Radio Network Subsystem (RNS)
`Core Network (CN)
`Protocol Architecture
`UMTS
`User Benefits of UMTS
`Seamless Global Roaming
`High-Speed Data Services
`Multimedia Services
`New Innovative Applications
`Telematics
`Increased Integration Between Fixed and Mobile
`Telephony Services
`Increased Choice of Services
`UMTS Future Vision
`Spectrum for UMTS
`The cdma2000 Family of Standards
`
`Contents '
`
`330
`331
`
`333
`
`334
`334
`336
`337
`337
`337
`338
`339
`340
`342
`344
`344
`344
`345
`345
`346
`347
`347
`347
`348
`349
`351
`351
`352
`352
`352
`352
`
`353
`353
`353
`354
`355
`
`Samsung, Exh. 1003, p. 18
`
`

`
`-
`
`-
`
`ACKNOWLEDGMENTS
`Well, here I am again, finalizing the latest book for McGraw-Hill. This one
`is different because it focuses on a single subject! The idea for this book
`came earlier this year, but has blossomed quite a bit since then because
`of the progress being made in the industry.
`This book deals with the issues surrounding the data and wireless
`industry as the two converge. I hope that this material is comfortable for
`you, the reader, because there is so little published about GPRS for the
`novice and business professional.
`To be fair about this production, I owe a lot of credit to many people.
`Some of the people interacted with me regularly, others only occasionally.
`First, I must thank Steve Chapman, who is McGraw-Hill's executive edi(cid:173)
`tor on this book and a super person. Steve knew that the deadlines were
`approaching, but kept his cool and kept after me. Numerous other people
`aided in the editing and production of the book-far too many to name.
`They know who they are and can give themselves a pat on the back for
`their efforts. Also worth special mention is Molly Applegate who has
`worked with me on two other books. Keeping track of books from the same
`author has to be a challenge in itself, especially when many of the topics
`seem to run together. Molly's usual tenacity got the final production
`together. Then there are the vendors and manufacturers we talk to daily
`regarding products, services, and opportunities. All add to the knowledge
`in this book.
`Two people in my office deserve the lion's share of the credits for the
`ultimate graphical representation and production of this book. First is
`Gabriele, who is my wife and partner of more than three decades. She is
`the steady contributor to my production. Gabriele truly deserves to have
`her name on the cover of this book because she has been a partner in the
`production of the preceding 14 books and barely gets mention. Second is
`a young lady whose energy and enthusiasm I have mentioned before:
`Amber Hartmann (our specialty graphics person). Amber and Gabriele
`worked dauntlessly to keep the graphics accurate and readable while at
`the same time creating interesting renderings. All this, despite the tech(cid:173)
`nical aspects of the drawings, had to be maintained. On more than one
`occasion, these two ladies were cursing the technical drawings because of
`their complexity. Yet, they both came through in record time.
`This team of people all pulled together to make GPRS a reality. They
`all deserve the credit more than I.
`
`Samsung, Exh. 1003, p. 19
`
`

`
`xviii
`
`Acknowledgments
`
`As usual, I want to especially thank you, the reader, for giving up your
`time to read this book. I receive many calls and e-mails from readers who
`just want to let me know that they enjoyed my opinion or the way I pre(cid:173)
`sented an idea. I hope I can continue to win your support. My best wishes
`to you all!
`
`Samsung, Exh. 1003, p. 20
`
`

`
`Introduction
`toGSM
`
`Samsung, Exh. 1003, p. 21
`
`

`
`2
`
`-
`
`-
`
`Chapter 1
`
`Objectives
`When you complete the reading in this chapter, you will be able to
`
`liil Describe the main components of a GSM network.
`oo Describe the mobile services.
`lll Understand how a mobile performs an attach or detach procedure
`inGSM.
`l!'l Discuss the modulation techniques used for GSM.
`Ill Understand the access methods used.
`m Describe the overall cellular operation of a radio network.
`
`Welcome to an overview of the General Packet Radio Services (GPRS).
`GPRS is a radio service that was designed to run on Global Systems for
`Mobile (GSM), a worldwide standard for cellular communications. Data
`transmissions in the past were slow across the radio interfaces due to many
`propagation and reception problems. To create a broadband communica(cid:173)
`tions interface, GPRS was developed as a stepping-stone approach to other
`services like the Enhanced Data for a Global Environment (EDGE).
`Regardless of the names we place on these services, the real issues are how
`much (cost) and how fast (speed) we need to meet the demands for data
`transmission now and in the future.
`Before delving directly into the GPRS systems and services, it is prudent
`to have common ground on the use of the radio-based systems. Therefore, a
`review (or introduction) of GSM is appropriate. After all, if GPRS is an over(cid:173)
`lay to GSM, we should at least understand how and why GSM works.
`
`History of Cellular
`Mobile Radio and GSM
`
`The idea of cell-based mobile radio systems appeared at Bell Laboratories
`in the early 1970s. However, the commercial introduction of cellular sys(cid:173)
`tems did not occur until the 1980s. Because of the pent-up demand and
`newness, analog cellular telephone systems grew rapidly in Europe and
`North America. Today, cellular systems still represent one of the fastest
`growing telecommunications services. Recent studies indicate that three of
`four new phones are mobile phones. Unfortunately, when cellular systems
`
`Samsung, Exh. 1003, p. 22
`
`

`
`Introduction to GSM
`
`3
`
`were first being deployed, each country developed its own system, which
`was problematic because
`
`1!11 The equipment only worked within the boundaries of each country.
`m The market for mobile equipment manufacturers was limited by the
`operating system.
`
`Three different services had emerged in the world at the time. They were
`
`II Advanced Mobile Phone Services (AMPS) in North America
`II Total Access Communications System (TACS) in the United Kingdom
`1111 Nordic Mobile Telephone (NMT) in Nordic countries
`
`To solve this problem, in 1982 the Conference of European Posts and
`Telecommunications (CEPT) formed the Groupe Special Mobile (GSM) to
`develop a pan-European mobile cellular radio system (the acronym later
`became Global System for Mobile communications). The goal of the GSM
`study group was to standardize systems to provide
`
`11 Improved spectrum efficiency
`ii International roaming
`II Low-cost mobile sets and base stations
`1111 High-quality speech
`ii Compatibility with Integrated Services Digital Network (ISDN) and
`other telephone company services
`1111 Support for new services
`
`The existing cellular systems were developed on analog technology. How(cid:173)
`ever, GSM was developed using digital technology.
`
`Benchmarks in GSM
`
`Table 1-1 shows many of the important events in the rollout of the GSM
`system; other events were introduced, but had less significant impact on the
`overall systems.
`Commercial service was introduced in mid-1991. By 1993, 36 GSM net(cid:173)
`works were already operating in 22 countries. Today, you can be instantly
`reached on your mobile phone in over 171 countries worldwide and on 400
`networks (operators). Over 550 million people were subscribers to GSM
`
`-
`
`Samsung, Exh. 1003, p. 23
`
`

`
`4
`
`Table 1-1
`
`Major Events in
`GSM
`
`Chapter 1
`
`Year
`
`Events
`
`1982
`
`1985
`
`1986
`
`1987
`
`1988
`
`1989
`
`1990
`
`1991
`
`1992
`
`1993
`
`1995
`
`CEPT establishes a GSM group in order to develop the standards for a pan(cid:173)
`European cellular mobile system.
`
`A list ofrecommendations to be generated by the group is accepted.
`
`Field tests are performed to test the different radio techniques proposed for
`the air interface.
`
`Time Division Multiple Access (TDMA) is chosen as access method (with Fre(cid:173)
`quency Division Multiple Access [FDMA]). The initial Memorandum of Under(cid:173)
`standing (MoU) is signed by telecommunication operators representing 12
`countries.
`
`GSM system is validated.
`
`The responsibility of the GSM specifications is passed to the European
`Telecommunications Standards Institute (ETSI).
`
`Phase 1 of the GSM specifications is delivered.
`
`Commercial launch of the GSM service occurs.
`
`The addition of the countries that signed the GSM Memorandum of Under(cid:173)
`standing takes place. Coverage spreads to larger cities and airports.
`
`Coverage of main roads GSM services starts outside Europe.
`
`Phase II of the GSM specifications occurs. Coverage is extended to rural areas.
`
`mobile telecommunications. 1 GSM truly stands for Global System for
`Mobile telecommunications. Roaming is the ability to use your GSM phone
`number in another GSM network. You can roam to another region or coun(cid:173)
`try and use the services of any network operator in that region that has a
`roaming agreement with the GSM network operator in your home
`region/country. A roaming agreement is a business agreement between two
`network operators to transfer items such as call charges and subscription
`information back and forth as their subscribers roam into each other's
`areas.
`
`1 As of May 2001
`
`Samsung, Exh. 1003, p. 24
`
`

`
`Introduction to GSM
`
`5
`
`GSM Metrics
`The GSM standard is the most widely accepted standard and is imple(cid:173)
`mented globally, owning a market share of 69 percent of the world's digital
`cellular subscribers. TDMA, with a market share close to 10 percent, is
`available mainly in North America and South America. GSM, which uses a
`TDMA access, and North American TDMA are two of the world's leading
`digital network standards. Unfortunately, it is currently technically impos(cid:173)
`sible for users of either standard to make or receive calls in areas where
`only the other standard is available. Once interoperability is in place, users
`ofGSM and TDMAhandsets will be able to roam on the other network type
`-subject to the agreements between mobile operators. This will make
`roaming possible across much of the world because GSM and TDMA net(cid:173)
`works cover large sections of the global population and together account for
`79 percent of all mobile subscribers, as shown in Figure 1-1.
`
`Cell Structure
`
`In a cellular system, the coverage area of an operator is divided into cells. A
`cell is the area that one transmitter or a small collection of transmitters can
`cover. The size of a cell is determined by the transmitter's power. The con(cid:173)
`cept of cellular systems is the use of low-power transmitters in order to
`enable the efficient reuse of the frequencies. The maximum size of a cell is
`approximately 35 km (radius), providing a round-trip communications path
`
`-
`
`-
`
`-Figure 1-1
`
`Market penetrations
`of GSM and TDMA.
`
`Samsung, Exh. 1003, p. 25
`
`

`
`6
`
`Chapter 1
`
`from the mobile to the cell site and back. If the transmitters are very pow(cid:173)
`erful, the frequencies cannot be reused for hundreds of kilometers, as they
`are limited to the coverage area of the transmitter. In the past when a
`mobile communications system was installed, the coverage blocked the
`reuse beyond the 25-mile coverage area, and created a corridor of interfer(cid:173)
`ence of an additional 75 miles. This is shown in Figure 1-2.
`The frequency band allocated to a cellular mobile radio system is dis(cid:173)
`tributed over a group of cells and this distribution is repeated in all of an
`operator's coverage area. The entire number ofradio channels available can
`then be used in each group of cells that form the operator's coverage area.
`Frequencies used in a cell will be reused several cells away. The distance
`between the cells using the same frequency must be sufficient to avoid
`interference. The frequency reuse will increase the capacity in the number
`of users considerably. The patterns can be a four-cell pattern or other
`choices. The typical clusters contain 4, 7, 12, or 21 cells.
`In order to work properly, a cellular system must verify the following two
`main conditions:
`
`lll The power level of a transmitter within a single cell must be limited in
`order to reduce the interference with the transmitters of neighboring
`
`-Figure 1-2
`
`The older way of
`handling mobile
`communications.
`
`Samsung, Exh. 1003, p. 26
`
`

`
`Introduction to GSM
`
`7
`
`cells. The interference will not produce any damage to the system if a
`distance of about 2.5 to 3 times the diameter of a cell is reserved
`between transmitters. The receiver filters must also conform.
`1111 Neighboring cells cannot share the same channels. In order to reduce
`the interference, the frequencies must be reused only within a certain
`pattern. The pattern may also be a seven-cell pattern, which is shown
`in Figure 1-3.
`
`In order to exchange the information needed to maintain the communi(cid:173)
`cation links within the cellular network, several radio channels are
`reserved for the signaling information. Sometimes we use a 12-cell pattern
`with a repeating sequence. The 12-cell pattern is really a grouping of three
`four-cell clusters, as shown in Figure 1-4. The larger the cell pattern, the
`more the coverage areas tend to work. In general, the larger cell patterns
`
`---(cid:173)
`
`Figure 1-3
`The seven-cell
`pattern.
`(Source: ETSI)
`
`---(cid:173)
`
`Figure 1-4
`The I 2-cell pattern.
`(Source: ETSI)
`
`Samsung, Exh. 1003, p. 27
`
`

`
`8
`
`Chapter I
`
`are used in various reuse patterns to get the most out of the scarce radio
`resources as possible. The 21-cell pattern is by far the largest repeating pat(cid:173)
`tern in use today. The cells are grouped into clusters. The number of cells in
`a cluster determines whether the cluster can be repeated continuously
`within the coverage area.
`The number of cells in each cluster is very important. The smaller the
`number of cells per cluster, the greater the number of channels per cell.
`Therefore, the capacity of each cell will be increased. However, a balance
`must be found in order to avoid the interference that could occur between
`neighboring clusters. This interference is produced by the small size of the
`clusters (the size of the cluster is defined by the number of cells per cluster).
`The total number of channels per cell depends on the number of available
`channels and the type of cluster used.
`
`-
`
`-
`
`Types of Cells
`The density of population in a country is so varied that different types of
`cells are used:
`
`Macrocells
`n Microcells
`II Selective or sectorized cells
`Umbrella cells
`11 N anocells
`11 Picocells
`
`Macrocells
`
`Macrocells are large cells for remote and sparsely populated areas. These
`cells can be as large as 3 to 35 km from the center to the edge of the cell
`(radius). The larger cells place more frequencies in the core, but because the
`area is rural, the macrocell typically has limited frequencies (channels) and
`higher-power transmitters. This is a limitation that prevents other sites
`from being closely adjacent to this cell. Figure 1-5 shows the macrocell.
`
`Samsung, Exh. 1003, p. 28
`
`

`
`Introduction to GSM
`
`---(cid:173)
`
`Figure 1-5
`The macrocel/.
`
`9
`
`Microcells
`
`These cells are used for densely