signal processing for mobile communications handbook - crc press - 2005

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signal processing for mobile communications handbook - crc press - 2005

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[...]... expression for the mth signal waveform in FSK modulations can be expressed in a general form as s m (t) = g (t) cos [2π f m t + θ] , m = 1, 2, , M 0≤t≤T (1.40) where g (t) is the signal pulse shape and f m = f c +m f ; m = 1, 2, , M, are the M possible equal-energy orthogonal frequencies with constant-phase angle θ that convey the transmitted information for M = 2k Copyright © 2005 by CRC Press. .. frequencies (in-phase and quadrature carriers), occupying identical frequency bands, are used to transmit data over a given physical channel The analytical expression for the mth signal waveform in the 4 http://www.qualcomm.com/cdma/3g.html Copyright © 2005 by CRC Press LLC (a) (b) FIGURE 1.6 8-QAM Constellations: (a) 4-4 ; (b) rectangular QAM technique can be expressed in a general form as s m (t)... transmitted signal In this case, the channel can be assumed to be static over one or several symbol durations r Doppler spread is smaller than the transmitted signal bandwidth r Channel varies slower than the baseband signal variations Copyright © 2005 by CRC Press LLC 1.2.2.3 Statistical Representation of the Small-Scale Propagation Channel For the signal processing applications and analyses, the mobile. .. the signal pulse shape, f c is the carrier mc ms frequency that conveys the transmitted signal information, and Amc and Ams are the information-bearing signal amplitudes of the quadrature carriers In Equation 1.38, for constant θm , s m (t) represents the PAM signal, while for constant Am it represents PSK signal By choosing the different amplitudes and phases, different constellations of QAM signals... parameters Copyright © 2005 by CRC Press LLC N-1 xN-1 Fade Amplitude N xu u x2 2 x1 1 Time P(u|1) P(v|u) P(u|u) P(1|1) P(2|1) P(u+1|u) P(u|u-1) u 1 P(1|2) P(u|u+1) P(u-1|u) P(u|v) P(1|u) FIGURE 1.2 Finite-state Markov-chain model of a non-interleaved fading channel As shown in Guan [Gua99], with the aid of probabilistic theory, the equilibrium channel state probability p(u) for state u, and the state... the baseband signal variations r In fast-flat fading channels the amplitude of the received signal varies faster than the rate of change of the transmitted baseband signal r In fast-frequency-selective channels the amplitudes, phases, and time delays of the multipath com- ponents vary faster than the rate of change of the transmitted signal 1.2.2.2.4 Slow Fading The received signal, in a mobile radio... modulating data signals shift the phase of the constant amplitude carrier signal between M number of phase angles The analytical expression for the mth signal waveform in PSK modulations has the general form s m (t) = g (t) cos [2π f c t + θm ], m = 1, 2, , M 0≤t≤T (1.35) where g (t) is the signal pulse shape and θm = 2π (m − 1)/M; m = 1, 2, , M are the M(M = 2 for binary PSK and M = 4 for quadrature... more signal power (Figure 1.5) Copyright © 2005 by CRC Press LLC s2 s3 s2 s1 s4 s1 (a) (b) FIGURE 1.4 Phase shift keying state diagrams: (a) BSPK, (b) QPSK 100 10−1 BER 10−2 64-QAM 64-PSK 10−3 4-QAM/PSK 10−4 16-QAM 16-PSK 10−5 10−6 0 5 10 15 SNR per bit 20 25 30 FIGURE 1.5 BER comparison between MQAM and MPSK techniques in the AWGN channel with optimum detection to achieve the same bit error rate performance... and Cimini [Cim99] to reduce the peak-to-average power ratio The successful use of the OFDM technique began in the sixties for high-frequency military systems (KINEOLEX, ANDEFT, KATHRYN) In the eighties the OFDM technique found application in highspeed modems, digital mobile communications, and high-density recording In the nineties the use of Copyright © 2005 by CRC Press LLC 1 0.8 0.6 0.4 0.2 0 −0.2... matrix is calculated using a ray-based approach, similar to geometrical optics The proposed Copyright © 2005 by CRC Press LLC model is shown to be valid for any Ricean factor, including the Rayleigh fading case This MIMO modeling approach accounts for the range dependency on a physical basis For more information on MIMO channel models see Chapters 13 to 15 of this book, and for further updates on other . infringe. Visit the CRC Press Web site at www.crcpress.com © 2005 by CRC Press LLC No claim to original U.S. Government works International Standard Book Number 0-8 49 3-1 657-X Library of Congress. of CRC Press LLC does not extend to copying for general distribution, for promotion, for creating new works, or for resale. Specific permission must be obtained in writing from CRC Press LLC for. class="bi x0 y0 w0 h0" alt="" CRC PRESS w York Washington, D.C. HANDBOOK Edited by Mohamed Ibnkahla SIGNAL PROCESSING FOR MOBILE COMMUNICATIONS This book contains information obtained from authentic

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Mục lục

  • Signal Processing for Mobile Communications Handbook

  • Copyright

  • Preface

  • Editor

  • Contents

  • Ch1 Signal Processing for Future Mobile Communications Systems: Challenges & Perspectives

    • Abstract

    • 1.1 Introduction

    • 1.2 Channel Characterizations

      • 1.2.1 Large-Scale Propagation Models

        • 1.2.1.1 Deterministic Approach

          • 1.2.1.1.1 Free-Space Propagation Model

          • 1.2.1.1.2 Log-Distance Path Loss Model

          • 1.2.1.2 Stochastic Approach

            • 1.2.1.2.1 Lognormal Shadowing Model

            • 1.2.2 Small-Scale Propagation Models

              • 1.2.2.1 Parameters of Mobile Multipath Channel

                • 1.2.2.1.1 Fading

                • 1.2.2.1.2 Doppler Shift

                • 1.2.2.1.3 Excess Delay

                • 1.2.2.1.4 Power Delay Profile,

                • 1.2.2.1.5 Delay Spread (Tm)

                • 1.2.2.1.6 Coherence Bandwidth (BWcoh)

                • 1.2.2.1.7 Doppler Spread (Bd)

                • 1.2.2.1.8 Coherence Time (Tcoh)

                • 1.2.2.2 Types of Small-Scale Fading

                  • 1.2.2.2.1 Flat Fading

                  • 1.2.2.2.2 Frequency-Selective Fading

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