第三代移动通信系统中信道估计技术的研究
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摘要
本文以第三代移动通信系统主流空中接口方案WCDMA系统为背景，主要研究了WCDMA上行链路RAKE接收机中的symbol级算法——信道估计技术。由于WCDMA系统上行链路采用的是基于相干解调的RAKE接收方案，故要求对信号在多径衰落信道中所经历的衰落作出准确实时的估计，以便在RAKE接收机中实现相位纠偏和相干接收。本文以WCDMA系统上行专用信道所采用的间断导频发送方式为背景，对几类实用的间断导频信道估计算法进行了研究，而且针对衰落信道的特征，对各类算法的性能作出了理论分析。并且，本文还就DFALP(基于判决反馈的自适应前向预测)算法的结构提出了一种改进算法DFALP-RAKE，该算法通过增加预判值的多径平均单元，改善了DFALP算法在低信噪比环境下的接收性能。最后，本文对讨论的几类算法进行了系统链路级仿真，通过仿真结果进一步验证了各种算法在不同信道环境下的接收性能；同时，仿真结果也表明，DFALP-RAKE改进算法的确能够使系统的接收性能在低信噪比环境下得到明显的改善。
The subject of this paper is channel estimation technology of the RAKE receiver in WCDMA system, which is the chief solution of the 3rd generation mobile communication. Since WCDMA up-link adopt the RAKE receiver using coherent detection system, the exact and Real-time channel fading estimation of the transmitted signal is needed to realize the phase correction and coherent reception. In this paper we bring out several applied channel estimation algorithm using time multiplexed pilot assisted transmission format. And we also analyze the performance of every algorithm under various fading conditions. In addition, this paper put forward a modified algorithm DFALP-RAKE. By adding a multipath averaging unit, the DFALP-RAKE algorithm improve the performance of the RAKE receiver. At last the paper include system simulation of all algorithms, and the result of simulation under different fading condition verify that the conclusion of analysis is reasonable. Also do the simulation results show the performance improvement of the modified DF ALP-RAKE algorithm in low SIR condition.
The subject of this paper is channel estimation technology of the RAKE receiver in WCDMA system, which is the chief solution of the 3rd generation mobile communication. Since WCDMA up-link adopt the RAKE receiver using coherent detection system, the exact and Real-time channel fading estimation of the transmitted signal is needed to realize the phase correction and coherent reception. In this paper we bring out several applied channel estimation algorithm using time multiplexed pilot assisted transmission format. And we also analyze the performance of every algorithm under various fading conditions. In addition, this paper put forward a modified algorithm DFALP-RAKE. By adding a multipath averaging unit, the DFALP-RAKE algorithm improve the performance of the RAKE receiver. At last the paper include system simulation of all algorithms, and the result of simulation under different fading condition verify that the conclusion of analysis is reasonable. Also do the simulation results show the performance improvement of the modified DF ALP-RAKE algorithm in low SIR condition.
引文
[1] 3GPP TS 25.211: "Physical channels and mapping of transport channels onto physical channels (FDD)".
[2] 3GPP TS 25.213: "Spreading and modulation (FDD)".
[3] 3GPP TS 25.104: "UTRA (BS) FDD: Radio transmission and Reception".
[4] 曾兴雯，刘乃安，通信中的扩展频谱技术，西安电子科技大学出版社，1996。
[5] 郭梯云，杨家玮，李建东，数字移动通信，人民邮电出版社，1995。
[6] 胡捍英，杨峰义，第三代移动通信系统，人民邮电出版社，2001。
[7] Tero Ojanpera, Ramjee Prasad, 宽带CDMA：第三代移动通信技术，人民邮电出版社。1998。
[8] 吴伟陵，移动通信中的关健技术，北京邮电大学出版社，2000。
[9] Harri Holma, Antti Toskala, WCDMA FOR UMTS-Radio Access For Third Generation Mobile Communications, JOHN WILEY & SONS.LTD, 2000.
[10] Theodore S.Rappaport, Wireless communication principles & practice, 电子工业出版社，1998。
[11] John G.Proakis, Digital Communication(Third Edition), 电子工业出版社，1995。
[12] 董霄剑，尤肖虎，WCDMA中一种新的信道估计方法，电子学报，2000，Vol．28 No7。
[13] 杨馨，赵新胜，尤肖虎，WCDMA下行信道RAKE接收机的性能分析，电子学报，2000，Vol．28 No11A。
[14] 董霄剑，蒋良成，尤肖虎，Rake接收机中信道最大多普勒频移估计的一种新方法及其在信道估计中的应用，电路与系统学报，2000，Vol．5 No3。
[15] J.K.caver, An Analysis of Pilot Symbol Assisted Modulation for Rayleigh Fading Channels, IEEE Trans. Veh, Vol.40 No4.
[16] Peter Schramm, Analysis and Optimization of Pilot-Channel-Assisted BPSK for DSCDMA Systems, IEEE Trans. on Comm, 1998 Vol.46 No9.
[17] H.Andoh,Mamoru SAWAHASHI, Channel Estimation Filter Using Time-Multiplexed Pilot Channel for Coherent RAKE Combining in DS-CDMA Mobile Radio, IEICE Trans. on Comm, 1998 Vol.E81-B No7.
[18] Chia-Liang Liu, Kamilo Feher, Pilot-Symbol Aided Cohenrent M-ary PSK in Frequency-Selective Fast Rayleigh Fading Channels, IEEE Trans, on Comm, 1994 Vol.42 No 1．
[19] Zhou Chunhui,Meng Lin, et al. An Order-adaptive Filter for Channel Estimation in DS-CDMA Mobile Systems, State Key Lab on Microwave and Digital Communications Department of Electronic Engineering, Tsinghua University.
[20] Sadayuki ABETA, Mamoru SAWAHASHI, Fumiyuki ADACHI, Adaptive Channel Estimation for Coherent DS-CDMA Mobile Radio Using Time-Multiplexed Pilot and Parallel Pilot Structures, IEICE Trans, on Comm, 1999 Vol.E82-B No9．
[21] Sadayuki ABETA, Mamoru SAWAHASHI, Fumiyuki ADACHI, Performance Comparison between Time-Multiplexed Pilot Channel and Parallel Pilot Channel for Coherent Combining in DS-CDMA Mobile Radio, IEICE Trans, on Comm, 1998 Vol.E81-B No7．
[22] Yong Liu, Steven D.Blostein, Identification of Frequency Non-selective Fading Channels Using Decision Feedback and Adaptive Linear Prediction. IEEE Trans, on Comm, 1995 Vol.43, No2/3/41．
[23] Bent Lindoff, CHANNEL ESTIMATION FOR THE W-CDMA SYSTEM, PERFORMANCE AND ROBUSTNESS ANALYSIS FROM A TERMINAL PERSPECTIVE, Ericsson Mobile Communications AB.
[24] Fumiyuki ADACHI, Adaptive Maximum Likelihood Detection of MPSK Signals in Frequency Nonselective Fast Rayleigh Fading, IEICE Trans, on Comm, 1997 Vol.E80-B No7．
[25] Mao-Ching Chiu ,Chi-chao Chao, Analysis of LMS-Adaptive MLSE Equalization on Multipath Fading Channels, IEEE Trans, on Comm, 1996 Vol.44, Nol2．
[26] Robert K.Morrow, Accurate CDMA BER Calculations with Low Computational Complexity, IEEE Trans, on Comm, 1998 Vol.46, No11．
[2] 3GPP TS 25.213: "Spreading and modulation (FDD)".
[3] 3GPP TS 25.104: "UTRA (BS) FDD: Radio transmission and Reception".
[4] 曾兴雯，刘乃安，通信中的扩展频谱技术，西安电子科技大学出版社，1996。
[5] 郭梯云，杨家玮，李建东，数字移动通信，人民邮电出版社，1995。
[6] 胡捍英，杨峰义，第三代移动通信系统，人民邮电出版社，2001。
[7] Tero Ojanpera, Ramjee Prasad, 宽带CDMA：第三代移动通信技术，人民邮电出版社。1998。
[8] 吴伟陵，移动通信中的关健技术，北京邮电大学出版社，2000。
[9] Harri Holma, Antti Toskala, WCDMA FOR UMTS-Radio Access For Third Generation Mobile Communications, JOHN WILEY & SONS.LTD, 2000.
[10] Theodore S.Rappaport, Wireless communication principles & practice, 电子工业出版社，1998。
[11] John G.Proakis, Digital Communication(Third Edition), 电子工业出版社，1995。
[12] 董霄剑，尤肖虎，WCDMA中一种新的信道估计方法，电子学报，2000，Vol．28 No7。
[13] 杨馨，赵新胜，尤肖虎，WCDMA下行信道RAKE接收机的性能分析，电子学报，2000，Vol．28 No11A。
[14] 董霄剑，蒋良成，尤肖虎，Rake接收机中信道最大多普勒频移估计的一种新方法及其在信道估计中的应用，电路与系统学报，2000，Vol．5 No3。
[15] J.K.caver, An Analysis of Pilot Symbol Assisted Modulation for Rayleigh Fading Channels, IEEE Trans. Veh, Vol.40 No4.
[16] Peter Schramm, Analysis and Optimization of Pilot-Channel-Assisted BPSK for DSCDMA Systems, IEEE Trans. on Comm, 1998 Vol.46 No9.
[17] H.Andoh,Mamoru SAWAHASHI, Channel Estimation Filter Using Time-Multiplexed Pilot Channel for Coherent RAKE Combining in DS-CDMA Mobile Radio, IEICE Trans. on Comm, 1998 Vol.E81-B No7.
[18] Chia-Liang Liu, Kamilo Feher, Pilot-Symbol Aided Cohenrent M-ary PSK in Frequency-Selective Fast Rayleigh Fading Channels, IEEE Trans, on Comm, 1994 Vol.42 No 1．
[19] Zhou Chunhui,Meng Lin, et al. An Order-adaptive Filter for Channel Estimation in DS-CDMA Mobile Systems, State Key Lab on Microwave and Digital Communications Department of Electronic Engineering, Tsinghua University.
[20] Sadayuki ABETA, Mamoru SAWAHASHI, Fumiyuki ADACHI, Adaptive Channel Estimation for Coherent DS-CDMA Mobile Radio Using Time-Multiplexed Pilot and Parallel Pilot Structures, IEICE Trans, on Comm, 1999 Vol.E82-B No9．
[21] Sadayuki ABETA, Mamoru SAWAHASHI, Fumiyuki ADACHI, Performance Comparison between Time-Multiplexed Pilot Channel and Parallel Pilot Channel for Coherent Combining in DS-CDMA Mobile Radio, IEICE Trans, on Comm, 1998 Vol.E81-B No7．
[22] Yong Liu, Steven D.Blostein, Identification of Frequency Non-selective Fading Channels Using Decision Feedback and Adaptive Linear Prediction. IEEE Trans, on Comm, 1995 Vol.43, No2/3/41．
[23] Bent Lindoff, CHANNEL ESTIMATION FOR THE W-CDMA SYSTEM, PERFORMANCE AND ROBUSTNESS ANALYSIS FROM A TERMINAL PERSPECTIVE, Ericsson Mobile Communications AB.
[24] Fumiyuki ADACHI, Adaptive Maximum Likelihood Detection of MPSK Signals in Frequency Nonselective Fast Rayleigh Fading, IEICE Trans, on Comm, 1997 Vol.E80-B No7．
[25] Mao-Ching Chiu ,Chi-chao Chao, Analysis of LMS-Adaptive MLSE Equalization on Multipath Fading Channels, IEEE Trans, on Comm, 1996 Vol.44, Nol2．
[26] Robert K.Morrow, Accurate CDMA BER Calculations with Low Computational Complexity, IEEE Trans, on Comm, 1998 Vol.46, No11．