Smart Antennas for Wireless Communications IS-95 and Third Generation CDMA Applications

by Liberti, Joseph; Rappaport, Theodore S.

• ISBN13: 9780137192878
• ISBN10: 0137192878
• Edition: 1st
• Format: Paperback
• Copyright: 1999-04-12
• Publisher: Prentice Hall

Summary

71928-6 IS-95 and Third Generation CDMA Applications. The one-stop source for engineering CDMA adaptive antennas. New adaptive ("smart") antenna arrays can enhance the performance of virtually any CDMA system, including IS-95, IMT-2000 and Wideband CDMA. Smart Antennas for Wireless Communications is the first book that brings together all the real-world data and expertise communications engineers need to develop smart antennas for CDMA. Start out with a detailed overview of IS-95 PCS and Cellular CDMA, including uplink and downlink signal formats and link budgets. Next, understand the full range of smart antenna technology, from simple beamforming networks to advanced multi-user spatial processing systems. Learn how adaptive antenna systems can change patterns dynamically, adjusting to noise, interference, and multipath as they track mobile users. Learn the key elements of smart antenna development, including vector channel impulse response, spatial signatures, spatial diversity, diversity combining, sectoring, and transmission beamforming. Understand important CDMA-related issues, including non-coherent and coherent CDMA spatial processors, dynamic re-sectoring, and the use of spatial filtering to increase range and capacity. Master all these fundamental design techniques: Characterization of spatio-temporal radio channels. The geometrically-based single bounce elliptical model. Optimal spatial filtering and adaptive algorithms. Direction-Of-Arrival estimation algorithms. This book reflects the latest developments in CDMA and smart antennas, including the IS-95 and J-STD-008 CDMA standards, 14.4K vocoders, andtechniques for designing RF location systems that meet the FCC's stringent E-911 requirements. Whether you're designing for today's CDMA systems or tomorrow's, you'll find it invaluable.

Author Biography

JOSEPH C. LIBERTI, JR. holds a Ph.D. in electrical engineering from Virginia Tech. He is currently a Research Scientist with Bellcore in Red Bank, New Jersey, where he is working on smart antenna technology and radio channel characterization for a variety of applications including CDMA, PACS, and other forward looking wireless systems.

THEODORE S. RAPPAPORT is the James S. Tucker Professor of Engineering at Virginia Tech, founder of the university's Mobile & Portable Radio Research Group, and Chairman of Wireless Valley Communications. He holds three patents and has authored, co-authored or co-edited 12 books, including Wireless Communications: Principles and Practice (Prentice Hall PTR).

Table of Contents

Preface	xv
Introduction	1	(40)
The Cellular Radio Concept	2	(3)
Evolution of Wireless Communications	5	(12)
Key Terms and Concepts in Wireless Communications	8	(3)
Digital Cellular and PCS Technologies	11	(1)
CDMA Wireless Local Loop	12	(2)
MMDS and LMDS	14	(1)
Third Generation (3G) Wireless Systems	14	(3)
Spread Spectrum and Code Division Multiple Access	17	(13)
Direct-Sequence Spread Spectrum	17	(6)
Multiple Access Interference in DS-CDMA Systems	23	(4)
Power Control and the Near-Far Problem in CDMA	27	(2)
Frequency Hop Spread Spectrum	29	(1)
Antenna Systems	30	(2)
Basic Concepts in Radiowave Propagation	32	(2)
Path Loss in Real World Channels	34	(1)
Small Scale Fading	34	(1)
Large Scale Path Loss	35	(4)
Log-distance Path Loss Model	36	(1)
Log-normal Shadowing	37	(2)
Summary	39	(2)
IS-95 PCS & Cellular CDMA	41	(40)
Cellular and PCS Frequency Allocation	41	(2)
PCS Frequency Allocation	42	(1)
How IS-95 CDMA PCS Systems Work	43	(5)
Soft and Softer Handoff in IS-95 CDMA Systems	46	(2)
Typical Link Budgets for IS-95 PCS	48	(1)
IS-95 Forward Link Budget for 1900 MHz	49	(1)
IS-95 Reverse Link Budget at 1900 MHz	49	(1)
Reverse Traffic Channel Transmission for IS-95	49	(21)
Variable Rate Vocoders	50	(5)
Error Control - The Frame Quality Indicator and Convolutional Coding	55	(2)
Symbol Repetition and Block Interleaving	57	(1)
Walsh Functions and 64-ary Orthogonal Modulation	58	(1)
Data Burst Randomization and Gating	59	(3)
Long Code Spreading	62	(2)
Quadrature (Short Code) Spreading	64	(2)
Reverse Access Channels	66	(2)
Reverse Access - Interaction Between Signals at the Base Station	68	(2)
IS-95 Forward Channel Signals	70	(8)
Forward Channel Transmitter Structures	70	(1)
The Pilot Channel	70	(2)
The Sync Channel	72	(1)
Paging Channels	72	(1)
Forward Traffic Channels	73	(2)
The Power Control Subchannel	75	(3)
Downlink Power Control	78	(1)
IS-95 Evolution and cdma2000	78	(1)
Summary	79	(2)
Introduction to Smart Antennas: Spatial Processing for Wireless Systems	81	(36)
Key Benefits of Smart Antenna Technology	81	(2)
Introduction to Smart Antenna Technology	83	(5)
The Vector Channel Impulse Response and the Spatial Signature	88	(1)
Spatial Processing Receivers	89	(2)
Fixed Beamforming Networks	91	(2)
Switched Beam Systems	93	(2)
Adaptive Antenna Systems	95	(4)
Wideband Smart Antennas	99	(3)
Spatial Diversity, Diversity Combining, and Sectoring	102	(3)
Digital Radio Receiver Techniques and Software Radios for Smart Antennas	105	(6)
Transmission Beamforming	111	(3)
Array Calibration	114	(2)
Summary	116	(1)
Smart Antennas Techniques for CDMA	117	(14)
Non-Coherent CDMA Spatial Processors	117	(2)
Coherent CDMA Spatial Processors and the Spatial Processing Rake Receiver	119	(4)
Multi-User Spatial Processing	123	(1)
Dynamic Re-sectoring Using Smart Antennas	123	(2)
Downlink Beamforming for CDMA	125	(5)
Summary	130	(1)
CDMA System Range and Capacity Improvement Using Spatial Filtering	131	(30)
Range Extension In CDMA	131	(3)
Single Cell Systems with Spatial Filtering at the IS-95 Base Station	134	(6)
Reverse Channel Performance of Multi-cell Systems with Spatial Filtering at the Base Station	140	(9)
Reverse Channel Spatial Filtering at the WLL Subscriber Unit	149	(2)
Range and Capacity Analysis Using Smart Antennas - A Vector-Based Approach	151	(8)
Summary	159	(2)
Characterization of Spatio-Temporal Radio Channels	161	(32)
Wireless Multipath Channel Models, Environment, and Signal Parameters	162	(10)
The Macrocell Environment	167	(1)
The Microcell Environment	168	(1)
Angle Spread	168	(1)
Measuring Time Variation of the Channel	169	(3)
Spatio-Temporal Channel Models for Smart Antennas	172	(15)
Lee's Model	173	(1)
Stapleton's Extension of Lee's Model	174	(1)
Discrete Uniform Distribution	174	(1)
Geometrically Based Single Bounce Statistical Channel Models	175	(1)
The Geometrically Based Single Bounce Circular Model (Macrocell Model)	176	(1)
The Geometrically Based Single Bounce Elliptical Model (Microcell Model)	177	(1)
The Gaussian Wide Sense Stationary Uncorrelated Scattering (GWSSUS) Model	178	(2)
Gaussian Angle-Of-Arrival (GAA)	180	(1)
Time-Varying Vector Channel Model (Raleigh's Model)	180	(2)
Two GSM Simulation Models (TU and BU)	182	(1)
The Typical Urban (TU) Model	182	(1)
The Bad Urban (BU) Model	183	(1)
The Uniform Sectored Distribution Model	183	(1)
Modified Saleh-Valenzuela's Model	184	(1)
Extended Tap-Delay-Line Method	185	(1)
Elliptical Subregions Model (Lu, Lo, and Litva's Model)	185	(1)
Measurement Based Channel Model	186	(1)
Ray Tracing Models	186	(1)
Spatial Channel Measurements	187	(4)
Application of Spatial Channel Models	191	(1)
Summary	191	(2)
The Geometrically Based Single Bounce Elliptical Model	193	(22)
Simulation of Multipath Component Parameters in GBSBEM	200	(5)
Marginal Distribution of the Direction-Of-Arrival in the GBSBEM Model	205	(4)
Doppler Spectra and the Fading Envelope	209	(3)
Selection of the Maximum Path Delay, τm	212	(2)
Summary	214	(1)
Optimal Spatial Filtering and Adaptive Algorithms	215	(38)
Impact of Multipath on Optimal Spatial Filtering	219	(6)
Flat Fading Channels	222	(1)
Frequency Selective/Time Dispersive Channels	222	(1)
Array Performance in Multipath	223	(2)
Performance of Underloaded and Overloaded Adaptive Arrays	225	(2)
Adaptive Algorithms	227	(7)
Blind Adaptive Algorithms	229	(1)
The Least Squares Constant Modulus Algorithm	230	(4)
Adaptive Algorithms for CDMA	234	(6)
Multitarget Least Squares Constant Modulus Algorithm	235	(1)
Gram-Schmidt Orthogonalization	236	(1)
Phase Ambiguity	237	(1)
Sorting Procedure	238	(2)
Multitarget Decision-Directed Algorithm (MT-DD)	240	(1)
Least Squares De-spread Re-spread Multitarget Array (LS-DRMTA)	241	(7)
Derivation of LS-DRMTA	242	(5)
Advantages of LS-DRMTA	247	(1)
Least Squares De-spread Re-spread Multitarget Constant Modulus Algorithm	248	(3)
Derivation of LS-DRMTCMA	248	(3)
Advantages of LS-DRMTCMA	251	(1)
Summary	251	(2)
Direction-Of-Arrival Estimation Algorithms	253	(32)
Conventional Methods for DOA Estimation	253	(3)
Delay-and-Sum Method	254	(1)
Capon's Minimum Variance Method	255	(1)
Subspace Methods for DOA Estimation	256	(13)
The MUSIC Algorithm	257	(5)
Improvements to the MUSIC Algorithm	262	(1)
Root-MUSIC Algorithm	263	(1)
Cyclic MUSIC Algorithm	264	(1)
The ESPRIT Algorithm	265	(4)
Maximum Likelihood Techniques	269	(3)
DOA Estimation under Coherent Signal Conditions	272	(4)
Spatial Smoothing Techniques	273	(1)
Multidimensional MUSIC	274	(2)
The Iterative Least Squares Projection Based CMA	276	(1)
The Integrated Approach to DOA Estimation	277	(2)
Detection of Number of Sources in Eigen Decomposition	279	(5)
The SH, MDL and AIC Criteria	280	(1)
Order Estimation Using Transformed Gerschgorin Radii	281	(3)
Summary	284	(1)
RF Position Location Systems	285	(20)
Direction Finding PL Systems	287	(1)
True Ranging PL Systems	288	(2)
Elliptical PL Systems	290	(1)
Hyperbolic PL Systems	291	(1)
Hyperbolic versus DF PL Systems	292	(1)
TDOA Estimation Techniques	293	(8)
General Model for TDOA Estimation	293	(2)
Generalized Cross-Correlation Methods	295	(2)
Hyperbolic Position Location Estimation Technologies	297	(2)
Methods for Hyperbolic PL Estimation	299	(2)
Measures of Position Location Accuracy	301	(3)
MSE and the Cramer-Rao Lower Bound	301	(1)
Circular Error Probability	302	(1)
Geometric Dilution of Precision	303	(1)
Summary	304	(1)
Appendix A Multiple Access Interference and the Gaussian Approximation	305	(10)
Appendix B Q, erf, & erfc Functions	315	(6)
Appendix C Mathematical Tables	321	(8)
Appendix D Abbreviations and Acronyms	329	(16)
References	345	(22)
Index	367	(8)
The Authors	375

Excerpts

Smart Antennas for Wireless CommunicationsIS-95 and Third Generation CDMA ApplicationsPrefaceThis text has been created to satisfy the growing demand for knowledge in two emerging areas: adaptive antennas (also known as smart antennas) and Code Division Multiple Access. CDMA was commercialized in the early 1990s by Qualcomm, Inc., a San Diego, California, company that pioneered the use of a classic military concept for the burgeoning cellular telephone industry. Adaptive arrays, first conceptualized in the 1960s with the birth of digital signal processing, only recently have become practical for deployment; the intense growth rates of wireless services around the world are beckoning for their commercial use.This text has been developed through years of research by the authors and their colleagues at the Mobile and Portable Radio Research Group of Virginia Tech and at Bell Communications Research. Our goal in creating this text is to provide fundamental and practical information for practicing engineers, students, and researchers in industry as well as in academia. To complement the book, the second author was asked by the Institute of Electrical and Electronics Engineers (IEEE) to provide a compendium of selected readings of key journal papers dedicated to the topic of smart antennas. The compendium, when used in conjunction with this text, provides a convenient single source of literature for use in classrooms or industry short courses.The material and organization of this book stemmed from the first author's 1995 Ph.D. dissertation on the subject of CDMA and smart antennas. Since then, a great deal of work has transpired in the field, including the adoption of the IS-95 J-STD-008 CDMA standard, the new 14,400 bps voice coder for Rate Set 2 channels, new methods and models for implementation and modeling of smart antennas in CDMA, and the stringent wireless E-911 position location requirement 125m, 67% of the time imposed by the Federal Communications Commission. We have worked diligently to include up-to-the-minute information in this text. The text is arranged into 10 chapters. Chapter 1 provides an overview of CDMA and smart antennas; it includes a glossary of terms and a fundamental treatment of synchronous and asynchronous CDMA. Antenna and propagation fundamentals, as they relate to CDMA systems, are also presented. Chapter 2 provides valuable practical information on the IS-95 J-STD-008 standard, and it provides in-depth descriptions of all of the CDMA channels. Also included is an actual link budget design for a PCS CDMA system. Chapter 3 provides fundamental material on adaptive antenna arrays and array theory. The concepts of beamforming, weighting vectors, and fixed-beam vs. adaptive beam antennas are covered. Chapter 4 applies this material to specific CDMA implementations that may be used for today's IS-95 and future CDMA systems. Chapter 5 combines the concepts of CDMA and adaptive antennas to derive analytical expressions that allow wireless system designers to predict the coverage and capacity gains that adaptive antennas provide in a multi-cell CDMA system. This chapter derives classic results that have led to system capacity predictions using CDMA with and without adaptive antennas.Chapter 6 provides an overview of multipath and Direction-Of-Arrival models for wireless channels. A host of propagation models which are useful for analysis and simulation of adaptive array algorithms are presented. Chapter 7 then describes complete details of one multipath propagation model, the Geometrically Based Single Bounce Elliptical Model, which provides complete characterization of a multipath environment in microcell/picocell applications. Chapter 8 describes optimal spatial filtering approaches that use both adaptive arrays and characteristics of the CDMA signals. Building on the fundamentals provided in Chapter 3, this chapter presents optimal methods that null interference while maximizing the carrier-to-noise ra