DESIGN AND PERFORMANCE OF 3G WIRELESS NETWORKS AND WIRELESS LANS DESIGN AND PERFORMANCE OF 3G WIRELESS NETWORKS AND WIRELESS LANS MOOICHOO CHUAH Lehigh University QINQING ZHANG Bell Laboratories, Lucent Technologies Springer Mooi Choo Chuah Lehigh University USA Qinqing Zhang Bell Laboratories, Lucent Technologies USA Design and Performance of 3G Wireless Networks and Wireless LANs ISBN 0-387-24152-3 e-ISBN 0-387-24153-1 ISBN 978-0387-24152-4 Printed on acid-free paper © 2006 Springer Science-l-Business Media, Inc All rights reserved This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, Inc., 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden The use in this publication of trade names, trademarks, service marks and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights Printed in the United States of America springeronline.com SPIN 11053408 This book is dedicated to our families Contents Preface xv Acknowledgments xvii Author Biographies xix Chapter INTRODUCTION TO WIRELESS COMMUNICATIONS 1 INTRODUCTION 1.1 Technology Evolution 1.1.1 Basic Principles 1.1.2 Multiple Access Technique 1.1.3 System Implementations 1.2 Techniques in Wireless Communications 1.2.1 Power Control 1.2.2 SoftHandoff 1.2.3 Adaptive Modulation and Coding 1.2.4 Space-Time Coding and Multiuser Diversity 1.3 Summary 1.4 References 1 2 6 10 10 11 Chapter INTRODUCTION TO WIRELESS SYSTEMS 13 13 14 15 INTRODUCTION 2.1 Generic Wireless System Architecture 2.1.1 Registration and Call Initiation viii Contents 2.1.2 Mobility Management 2.1.3 Call Delivery 2.1.4 Handoff 2.2 Traffic Routing in Wireless Networks 2.3 First- and Second-Generation Cellular Radio Network 2.4 Deficiencies of First- and Second-Generation Wireless Systems 2.5 Second-Generation Cellular Networks Offering Wireless Data Services 2.6 Third-Generation Wireless Networks and Wireless LANs 2.7 Transport Choices for Wireless Backhaul Networks 2.8 End-to-End Protocol Stack 2.8.1 Circuit Switched Service 2.8.2 Packet Data Service 2.9 RLC/MAC Functions 2.10 Review Exercises 2.11 References 16 16 17 17 18 20 21 22 24 28 28 29 30 35 36 Chapter INTRODUCTION TO TRAFFIC ENGINEERING 39 39 40 41 43 43 43 44 44 47 50 52 59 59 INTRODUCTION 3.1 QoS Requirements of Internet AppUcations 3.2 UMTS QoS Classes 3.2.1 Conversational Class 3.2.2 Streaming Class 3.2.3 Interactive Class 3.2.4 Background Class 3.3 QoS Engineering 3.4 Traffic Modeling 3.4.1 Traffic Model Framework 3.4.2 Methodology for Traffic Characterization 3.5 Review Exercises 3.6 References Chapter OVERVIEW OF CDMA2000/UMTS ARCHITECTURE 61 61 62 63 INTRODUCTION 4.1 Evolution of CDMA2000 Standards 4.2 Overview of CDMA2000 3Glx Network Architecture 4.3 Overview of CDMA2000 xEV-DO Network Contents Architecture 4.4 Overview of 3GPP Standards Evolution 4.5 Overview of UMTS R99/4 Network Architecture 4.5.1 UTRAN Components 4.5.2 General Protocol Model for UTRAN Terrestrial Interfaces 4.5.3 Core Network Components 4.5.4 General Protocol Model for CN Interfaces 4.6 Mobility Management 4.6.1 Circuit-Switched Services 4.6.2 Packet Services 4.7 Review Exercises 4.8 References ix 66 67 68 70 72 80 83 84 85 86 88 89 Chapter AIR INTERFACE PERFORMANCE AND CAPACITY ANALYSIS 91 91 CAPACITY ANALYSIS AND EVALUATION 5.1 Queuing Analysis in a Wireless Communication System 5.1.1 Call Arrival Process 5.1.2 Birth-Death Process 5.1.3 Lost Call Cleared and Lost Call Held 5.2 Erlang Capacity for Circuit-Switched Services 5.2.1 Capacity Analysis on Reverse Link 5.2.2 Capacity Analysis on Forward Link 5.3 Capacity for Packet Switched Services 5.4 Simulation Methodologies for Capacity Evaluation 5.4.1 System Level Simulation Assumptions for Forward Link 5.4.2 System Level Simulation Assumptions for Reverse Link 5.4.3 Performance Criteria and Output Metrics 5.5 Comparison of Analytical Models with Simulations 5.5.1 Comparison of Analytical and Simulation Results on Reverse Link 5.5.2 Comparison of Analytical and Simulation Results on Forward Link 5.6 Review Exercises 5.7 References 91 91 93 94 96 96 105 Ill 112 112 115 118 119 120 124 127 127 X Contents Chapter DESIGN AND TRAFFIC ENGINEERING OF A BASE STATION 129 BASE STATION DESIGN 129 6.1 UMTS Base Station Design 130 6.1.1 CPU Budget for Various Component Cards in NodeB 130 6.1.2 lub Interface Capacity 141 6.2 Capacity Evaluation and Resource Management of IxEV-DO Base Stations 148 6.2.1 IxEV-DO Base Station Architecture 148 6.2.2 Processor Occupancy Analysis 149 6.2.3 Processor Performance Enhancements 155 6.3 Review Exercises 158 6.4 References 158 Chapter RNC AND RADIO ACCESS NETWORKS DESIGN AND TRAFFIC ENGINEERING : 159 INTRODUCTION 7.1 RNC Design 7.1.1 Overview of Generic RNC Hardware Architecture 7.1.2 RNC Capacity 7.1.3 Traffic Model Revisited 7.1.4 Impacts of RAB Inactivity Timer Value on Signaling Traffic and Power Consumption 7.1.5 Radio Resource Management 7.2 Techniques for Improving OPEX/CAPEX of UMTS RAN 7.3 Review Exercises 7.4 References 159 159 160 160 162 172 174 181 188 189 Chapter CORE NETWORK DESIGN AND TRAFFIC ENGINEERING 191 191 INTRODUCTION 8.1 Registering and Activating the Circuit/Packet Switched Service 8.1.1 Routing Area Update 8.1.2 Activating a Packet Data Session 8.1.3 Receiving a CS Domain Call 8.2 SGSN 8.3 GGSN 8.4 GPRS/UMTS GTP Tunnel 192 194 195 196 196 200 200 Contents 8.5 Capacity Sizing of SGSN/GGSN 8.5.1 Signaling Load Estimate 8.6 Overload Control Strategy 8.7 Scheduling/Buffer Strategies 8.7.1 Scheduling Algorithms 8.7.2 Buffer Management Schemes 8.7.3 Performance Evaluations of Different Scheduling/Buffer Management Schemes 8.8 Distributed/Centralized Core Network Design 8.9 Review Exercises 8.10 References xi 202 203 208 211 211 213 215 219 222 223 Chapter END-TO-END PERFORMANCE IN 3G NETWORKS 225 225 225 227 229 237 INTRODUCTION 9.1 Call Setup Delay for Circuit Switched Service 9.1.1 Delay Analysis of the Call Setup Procedure 9.1.2 End-to-End Delay Analysis for Voice Bearer 9.2 End-to-End TCP Throughput in 3G Networks 9.2.1 Simple Analytical Model for Studying RLC Performance 9.2.2 Analytical Model of RLC 9.2.3 Simulation Studies of RLC/MAC Performance 9.2.4 Deadlock Avoidance in RLC 9.3 Recommendations of TCP Configuration Parameters over 3G Wireless Networks 9.4 Some Proposed Techniques to Improve TCP/IP Performance in 3G Networks 9.5 Review Exercises 9.6 References 241 242 246 248 250 252 254 254 Chapter 10 OVERVIEW OF WIRELESS LAN 257 10 INTRODUCTION 10.1 Overview of 802.11 Wireless LAN 10.1.1 Wireless LAN Architecture and Configurations 10.1.2 802.11b 10.1.3 802.11a 10.1.4 802.11g 10.2 802.11 Physical Layer 10.3 Capacity and Performance of 802.11 System 10.3.1 Coverage and Throughput Performance 10.3.2 Impact of Co-Channel Interference on 257 259 259 260 262 264 266 267 267 334 Introduction to Probabilities and Random Process The conditional density of j ; assuming x = x is of particular interest It can be proved that We have the following probabilities of the conditional density functions > fÄy\A=^-M my)-^-M fx{x) (A-26) fy{y) If the random variables x and y are independent, we have f{x,y) = f{x)f{y) fy{y\x) = f{y) mdf,{x\y) = f{x) f{x,y) = f{y\x)f{x) (A-27) (A-28) Bayes' theorem f{y) Conditional expected values The conditional mean and variance of y are //„ = E{y I x} = [^yf{y \ x)dy < =E[(y-Mj I x} = l^y-^ij (A-30) f{y I x)dy 12.5.1.1 FunctCalculation of the mean and variance f random variables forms a new random variable with outcomes consisting of the events determined by the function itself (A-31) Introduction to Probabilities and Random Process 335 Let us assume that jc is a random variable and y = g{x) is a function of jc Then j ; is defined as a new random variable with its domain including the range of the random variable jc The distribution function of y can be expressed by the distribution function of jc and the function g{x) Fy{y) = P{y0 (A-60) A.3.7 Rayleigh Distribution A random variable jc is Rayleigh distributed if its probability density function is represented by 342 Introduction to Probabilities and Random Process f{x)^^e-^'"-\x>Q a (A-61) Suppose a complex signal is the sum of two quadrate Gaussian signals as z = re^^ =x-\-jy (A-62) where x and y are i.i.d Gaussian random variables with zero mean and variance of cr^ The envelope of the signal r = ^Jx^ + 7^ is a random variable with density function / ( r ) Since x and j are i.i.d., we have f{x,y) = f{x)f{y) (A-63) Since df{r)^df{r)dr^df{r)x dr dx dx dr r Taking differentiation on (A-63) with respect to x, we have -r{r) = r{x)f{y) (A-64) = ^r{x)f{y) X (A-65) or -r{r) r Similarly, we have \nr) = ^^f{x)r{y) (A-66) From (A-65) and (A-66), we show that the probability density function/fr) is circular symmetric Introduction to Probabilities and Random Process 343 The mean and variance of a Rayleigh distributed random variable are given by 7.=^{^} = ^ | ö - (jl=E[r'\-E'ir\42~ E[r^}-E^{r} (A-67) a^ (A-68) Rayleigh distribution is widely used to model the wireless fading channel [Rap][Jak74] The received signal over the air usually does not have a direct line-of-sight to the transmitter The transmitted signal is scattered by randomly placed obstructions and results signals with different attenuations and phases This is so called multipath propagation As a consequence, the received signal is the sum of the signals from multiple paths Each scattered wave is a complex signal with a random amplitude and a phase Let a/ and Oi denote the amplitude and phase of the zth wave respectively, the received signal from n waves is thus received -re^' ^Y.^fi^'' (A-69) Further, we have ce,ve = ' ' ^ ' ' =Z«/Cos(Ö/) + ^•Z«-sin(Ö/)-^ + ^ /=1 (A-70) /=1 The amplitude of individual wave a, is random, and the phase ^ is uniformly distributed Since the number of scattered wave n is large, from the central limit theorem, x and y approach to Gaussian distribution with zero mean and same variance From (A-70), we conclude that the envelop of the received signal has a Rayleigh distribution as shown in equation (A-61) For a special case «=2 and y-4x in the Chi-square distribution, we obtain the Rayleigh distribution with the density function denoted by (A-61) 344 Introduction to Probabilities and Random Process A.3.8 Rician Distribution A random variable x is Rician distributed if its probability density function is represented by ""^ ; , x > a' (A.71) \0- where /Q (•) is the modified (/^ order Bessel function given by L ''ca\ I -, O OX XC CO OSS^^ J— p2^ \ fi" = — [ e " d9 (A-72) The Rician distribution is another widely used model for the wireless fading channels It is used to model the fading channel when there is a direct line-of-sight path The Rayleigh fading model characterizes the scenario of indirect multi-path propagation However, in some environment such as the indoor propagation, there is a direct path dominating over the indirect multiple paths Therefore the received signal is the sum of the scattered and direct signals, which is given by Srece>.ed-reJ'={x + a) + jy (A-73) Following the same procedures in deriving (A-61), we can obtain the probability density function of the received envelop as in (A-71) It should be noted that if a=0 in (A-73), we obtain the Rayleigh distribution If a/a is very large, the signal will be dominated by the in-phase part (x+a) The distribution of r will approach to the distribution of jc with a mean value of a A.4 Review Exercises Consider a random variable x = x^-{-X2-\ HJC„ Suppose that random variables Xi are i.i.d and uniformly distributed in the interval (0,1) Express the density function /^{x) with n=2 and n=5 Compare the density function with the normal distribution using the central limit theorem Prove the Bayes' theorem in equation (A-29) Introduction to Probabilities and Random Process 345 Prove that the mean and variance of a lognormal random variable are expressed as in equations (A-46) and (A-47) Derive the Rician distribution of the envelop of the received signal as inequation (A-71) A.5 References [Pap91] Athanasios PapouHs, Probability, Random Variables, and Stochastic Processes, Third Edition, McGraw-mil 1991 [Sch92] S C Schwartz, Y S Yeh, "On the Distribution Function and Moments of Power Sums With Log-Normal Components," The Bell System Technical Journal, Vol 61, No 7, pp 1441-1462, September 1992 [Rap] T, S Rappaport, T Rappaport, Wireless Communications: Principles and Practice (2""^ Edition), Prentice Hall, December 2001 [Jak74] W Jakes, Mobile Communications, CRC Press, 1974 Index IxEV-DO, ix, X, 67, 70, 71, 142, 161, 172 3Glx, ix, 52,54, 58, 68,69, 70, 71,159, 161,277 802.1 la, xii, 283, 286,287,288,289, 290,292,293,294,295,296,297, 298,299, 300, 302, 303, 305, 328, 329 802.1 Ib, xii, xiii, 283,284,285, 286, 287,288,289, 290,291,293, 294, 295,296,297, 298,299, 300, 301, 302,303,305,306,312,313,314, 315,317,320,324,325,329 802.1 le, xiii, 283, 306, 321, 322, 323, 324,328, 329 802.1 lg, xii, 283,289,290, 292, 293, 294,295,299, 300, 301, 302, 303, 305,328 802.15.3, xiii, 306, 326, 327, 328 802.16, xii, 301, 302, 303 AAA server, 70 AAL5,81,150,222 Access technique, xvi, 2, 3,4, 5, 6, 7, 9, 12,22, 26, 28, 37,38,48, 51, 66, 71, 97,102,113,115,129,138,142,159, 161,162,275,287,302, 340, 348 acknowledged mode, 264 adaptive modulation, xvi, 10 ALCAP, 78, 143,144, 146, 148,149, 151,152, 181, 182,185,187 AMPS, 3,4, 6, 21,22,24,39 APN, 211 birth-death process, 99,100 bluetooth, 303 BTS, 28, 30, 68, 69,121,124 buffer management, 212,234, 238, 241,242 call arrival, 98,100,105,114,119 call setup delay, 248,252,278 capacity analysis, 102,119 CDMA, 2, 3, 6, 7,9,12, 22,26,28, 37, 38,51,66,71,97,102,113,115,129, 138,142,159, 161, 162,275, 340, 348 CDMA2000, ix, xiii, xv, xvi, 6, 7, 10,25, 40,41,65,66,67,68,69,70,122, 141,161,172,261,275,332,339, 341,342,356 CDPD, 15,23,24,39 Cell_DCH, 89, 90, 149, 183, 185,186, 191,193,195,196,205,206,207 CFP, 309, 310, 319, 321, 322, 326 CGF, 211,221 circuit switched, 31,55,64,108, 111, 116,119,127,130,179,180,211, 218,252 co-channel interference, 2, 7,291,296, 297,298,299, 303 connection estabUshment, 144,145, 179,181,182,249,251,252 CP, 309, 310, 318, 319,322 CPU budget, 141, 142, 143, 144,149, 153,172 CTS, 300, 301, 303, 306,309, 326 348 CWmax,307,308,313 CWmin, 307, 308, 313, 314, 321 DCF, xiii, 305, 306, 307, 309, 311,312, 321,325 deadlock avoidance, 274 DHCP, 71,211 DIPS, 306, 307, 309, 312, 326 DRNC, 75, 76, 83, 85, 183,259, 260, 347 DSCH, 349,350, 356 DSSS, 285,291, 308, 312, 313 EDCF, 306, 321, 322, 323 EMS, 68, 69 Erlang capacity, 97, 102,105, 106, 109, 114 FACH, 51, 89, 91, 183, 189, 193, 194, 195, 196, 197, 199, 200, 349, 350, 351,356 FDMA, xvi, 2, 7, 9, 97 Frame Protocol, 83, 84, 146, 148,154, 158 FSSS, 285 GGSN, xi, 43, 74, 85, 87, 88, 92, 93, 199, 211, 212, 216, 220, 221,222, 224, 225, 230, 233, 234, 238, 239, 242, 243, 244, 245, 255, 256, 258, 260, 345 GPRS, xi, 4, 5, 6, 12, 24, 33, 43, 73, 74, 82, 85, 86, 87, 88, 91, 92, 94, 95,211, 213, 215, 219, 221, 222, 223, 246, 279, 335 GSM, 3,4, 5, 6, 12,13, 22, 24,26,43, 48,73,91,261 GTP, xi, 33, 82, 87, 88,92, 211,216, 219,221, 222, 223,224,230,233,345 hardware architecture, 176,185 HLR, 17, 18,22, 73, 86, 87, 92, 93,211, 215,217,218,219,222 IMS, xiii, 331, 332, 333, 334, 335, 338, 356 inactivity period, 190 inter-cell interference, 8,103,109,110, 129,131,132 IR, 285, 291, 308 IS-136,5, 13,22 IS41,21,40 IS-95, 6, 66,122 lub interface, 73, 75, 82, 143, 144, 154, 155,157,158,177,200,207,250 Iu-CS,75,79,80,81 Index Iu-PS,75,81,219,229 lur, 74, 77, 78, 82, 83, 84, 85, 94, 95, 154, 172, 177, 209, 255, 259, 260, 347, 356 location updates, 179,181,183 lost call cleared, 100 lost call held, 100,101 mobile originated, 144,148,248,252 mobile switching center, 16, 26, 27, 93 mobile terminated, 252 mobility management, 5,17,24,26, 32, 69, 72, 85, 88, 89, 91, 92, 93, 94, 333 MTP3, 80, 81, 87, 214, 220, 226 multicastlDroadcast, 331, 339, 341 multiplexing gain, 158, 186, 193 Multi-user diversity, 11 NAS, 145, 146, 147,179, 182, 183, 251, 252 NBAP, 32, 78, 82, 95, 143, 146, 147, 148, 149, 150, 151, 152, 176, 181, 184 OFDM, 286,287, 288, 289, 292, 300, 302,305 OPEX,xi, xvi, 175,200 outage probability, 104, 105, 107, 108, 109,110,111,112, 113,114,115, 116,117,118,119,127,129,130, 133,134, 135, 137, 138 outdoor 802.11-based, 325 overload control, 212,231,232,233 packet switched, 31, 55,118,119,127, 177,179,182,183,211,213,217, 233,333 path loss, 7,109,110,115,120, 124, 129,290, 292,293, 294, 302, 342, 349 PC, 64, 122,281,309,310,322 PCF, 68, 69, 70, 305, 306, 309, 310, 311, 317,320,321,325,329 PDP, 86, 92, 149,216,218,219, 224, 225,226, 227, 229, 230, 233, 246, 335,353 PDP context activation, 92,216,218, 225,226, 230, 246 PDSN, 68, 69, 70, 71, 340, 341 physical layer design, 291 PIFS, 309, 310, 311, 321, 322 PLMN,74,89,93,213 p-median, 243 Index PoC, xiii, 332, 351, 352, 353, 354, 355, 356 power control, xvi, 7, 8, 9,51, 66,67, 75,76,82,83,103,105,106,109, 111,114,122,126,129,130,131, 132,134,176,248,342,349,350 processor occupancy, 153,154,161, 163,164, 167, 168 protocol model, 77 protocol stack, 16,29,31,32, 71, 80, 81,82,83,88,154,159,165,170, 220,221,317 push-to-talk, 332 QoS, viii, xvi, 15,25, 28, 33,40,43,44, 45,46, 49, 50, 64, 67, 143, 154, 159, 200, 212, 234, 240, 242, 306, 321, 322, 326, 327, 328, 329 QoS engineering, 43,49 QoS mapping, 50 RA,92, 149, 183,184,216 RAB, xi, 82, 146, 147, 160, 189, 216, 225,226, 227, 229, 230, 246, 249, 250, 252 RANAP, 32, 76, 78, 80, 81, 86, 89,94, 144,146,147,149,176,181,217, 220,249 RAU,225,226 registration, xvi, 18,22,69, 83, 90,183, 189,213,219,335,341 RLC/MAC, viii, xii, 16,31, 34, 38, 55, 89,154, 238,247, 261, 263, 270,278 RNSAP, 78, 83, 84, 85, 95 routing, 19, 24, 27, 73, 86, 91,93, 149, 162,164,170,215,217,219,221, 222,225,226,228,230, 346 routing area, 86,91,149,215,219, 221, 225,226,228, 230 RRC, 32,75, 89, 90, 91, 144, 145, 146, 147, 148, 149, 179, 181, 182, 184, 215,216, 217,249,250,251, 252, 278,279, 347 RTS, 300, 301, 303, 306,309 scheduling, 50,67, 85,119,120,153, 154,212, 234, 235,238,242,248, 277,279, 322 SDU, 46,47, 262,274, 319 session set up, 338 349 SIFS, 307, 308, 309, 310, 312, 323, 325 signaling load, 190,225,226, 227,230, 246 spread spectrum, xvi, 6, 7,97,102,283, 291 SRNC, 33, 76, 83, 85, 90, 144, 145, 146, 147,148,183,184,185,217,248, 258, 260, 347 STTD, 350, 356 TCP configuration, 275 TCP fairness, 315,329 TDMA, xvi, 2, 3,4, 5, 7, 9, 22, 26, 37, 48,71,97,287,302 TFC, 262 timing adjust, 156,157,158,172 TMSI,89,214,215 traffic characterization, 58,62 traffic model, xvi, 52, 55, 56, 120, 127, 160, 177, 178, 179, 181, 182, 185, 186,198,207,224,227,229 transport format set, 159,201 TTI, 152, 154, 155, 159, 161, 197, 198, 199,200,262, 268,270,278, 350 UMTS QoS class, 45,46 unacknowledged mode, 31 URA, 89, 90, 91,149, 172, 177, 182, 183, 184, 185, 186, 187, 189, 190, 191,205,207,209 URA_PCH, 89, 90, 91,149, 172,183, 184,185, 186, 190, 191,205,207, 209 UTRAN, ix, 40, 72, 73, 74, 75, 76, 77, 79,83,86,89,90,91,94,95,158, 172,177,183,189,205,209,211, 233,256 VLR, 17,22, 74, 93,213, 214, 217 voice bearer delay, 278 voice services, 15,16,17,107, 217, 247,306,317,318,329,352 weighted round robin, 240,241 wireless backhaul, 15, 39 wireless LAN, xv, xvi, xvii, 25,281, 282,283,284, 286, 288,289,290, 292,293,294, 295, 296,297,299, 301,305,306,316,329 WLAN, xiii, 25, 41,281,285, 315, 317, 321,324,325