天波信道下OFDM系统信道估计与迭代均衡技术研究
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摘要
短波通信在远程通信中起着举足轻重的作用,随着通信技术的不断发展,寻求一种方便可靠的高速远程短波通信手段是我们不断努力的方向。对于短波通信而言,多径时延扩展以及多普勒频偏等复杂时变的信道特性已经成为制约短波通信传输速率提高的一个主要瓶颈。正交频分复用(OFDM)技术由于其高效的频谱利用率和有效的抗多径能力,在短波通信系统的应用中受到了越来越多的关注,成为提高短波通信传输速率的一个重要的研究方向。
在OFDM系统中,由于多径和其它各种因素的影响,接收信号需要通过信道估计和均衡来补偿信道特性不理想所造成的性能损失,这就对系统的信道估计和均衡技术提出了一定的要求。本文以短波OFDM通信系统中的这两个关键技术为研究重点,对其开展了详细的研究。本文的章节内容安排如下：
第一章对短波通信和OFDM技术的特点及其发展概况进行了简要的阐述,介绍了基于OFDM技术的短波通信系统的研究现状,给出了本文的主要工作安排。
第二章主要介绍了短波信道的特性和OFDM系统基本原理,讨论了短波信道模型,同时给出了短波OFDM系统模型,分析了短波信道对OFDM系统的影响,引出了短波OFDM系统需要解决的几个关键技术,即信道估计和信道均衡技术。
第三章重点研究了短波OFDM系统中的信道估计技术,对几种基本的信道估计算法进行了详细的介绍,然后从短波天波信道的模型及特性出发,提出了一种适用于短波天波信道的信道估计技术,并在此基础上给出了其改进方案。
第四章讨论了短波OFDM系统中的信道均衡技术,对基本的信道均衡算法加以详细介绍。并在Turbo均衡技术的基础上,提出了一种短CP情况下的OFDM均衡技术,仿真分析了CP的长短和信道估计结果对提出的算法性能的影响。
第五章主要研究了短波多天线OFDM系统中的Turbo均衡技术。首先对单发多收和多发多收OFDM系统的信号模型、基本结构进行阐述,然后将Turbo均衡技术应用到短波多天线OFDM系统中,提出应用于短波多天线系统的Turbo均衡技术,给出了Turbo均衡在多天线系统中的理论推导,并对其性能进行仿真。
The High-Frequency communication plays an important role in remote communication. With the development of communication technology, seeking a convenient and reliable means of high-speed HF communication is our goal. In HF communication, the domain obstacle to further increase the data rate of transmission is the channel distortion caused by multipath delay spread and Doppler shift. Because of the efficient spectrum utilization and the effective anti-multipath capability, the usage of OFDM in HF communication has received extensive attention.
Because of the selective fading caused by multipath and various other factors, OFDM need channel estimation and equalization to compensate the channel characteristic so that the performance loss of demodulation could be minimized. This thesis is focus on these two key techniques for OFDM system used in HF communication, and carries out a detailed study. This thesis is organized as follows:
Chapter one gives an overview of HF communication and OFDM technology, and introduces the researches of the OFDM-based HF communication systems.
Chapter two gives the HF channel model and HF OFDM system model. Through the analyzing of the channel effect in OFDM system, leads to several key technologies need to be solved, which are channel estimation and channel equalization technologies.
In Chapter three, we focus on the channel estimation techniques in the HF OFDM system. Several basic channel estimation algorithms are described in detail. Then from the HF channel characteristics, we design a channel estimation technique which is suitable for HF channel, and discuss the improvement scheme based on this technique.
Chapter four discusses the channel equalization techniques in the HF OFDM system. We design an iterative equalization algorithm for the OFDM systems with short CP. The length of the CP and the channel estimation results on the performance of the proposed algorithm are analyzed by simulation.
Chapter five proposes the iterative equalization techniques with theoretical derivation in the multi-antenna HF OFDM systems, and gives the performance simulation results.
在OFDM系统中,由于多径和其它各种因素的影响,接收信号需要通过信道估计和均衡来补偿信道特性不理想所造成的性能损失,这就对系统的信道估计和均衡技术提出了一定的要求。本文以短波OFDM通信系统中的这两个关键技术为研究重点,对其开展了详细的研究。本文的章节内容安排如下：
第一章对短波通信和OFDM技术的特点及其发展概况进行了简要的阐述,介绍了基于OFDM技术的短波通信系统的研究现状,给出了本文的主要工作安排。
第二章主要介绍了短波信道的特性和OFDM系统基本原理,讨论了短波信道模型,同时给出了短波OFDM系统模型,分析了短波信道对OFDM系统的影响,引出了短波OFDM系统需要解决的几个关键技术,即信道估计和信道均衡技术。
第三章重点研究了短波OFDM系统中的信道估计技术,对几种基本的信道估计算法进行了详细的介绍,然后从短波天波信道的模型及特性出发,提出了一种适用于短波天波信道的信道估计技术,并在此基础上给出了其改进方案。
第四章讨论了短波OFDM系统中的信道均衡技术,对基本的信道均衡算法加以详细介绍。并在Turbo均衡技术的基础上,提出了一种短CP情况下的OFDM均衡技术,仿真分析了CP的长短和信道估计结果对提出的算法性能的影响。
第五章主要研究了短波多天线OFDM系统中的Turbo均衡技术。首先对单发多收和多发多收OFDM系统的信号模型、基本结构进行阐述,然后将Turbo均衡技术应用到短波多天线OFDM系统中,提出应用于短波多天线系统的Turbo均衡技术,给出了Turbo均衡在多天线系统中的理论推导,并对其性能进行仿真。
The High-Frequency communication plays an important role in remote communication. With the development of communication technology, seeking a convenient and reliable means of high-speed HF communication is our goal. In HF communication, the domain obstacle to further increase the data rate of transmission is the channel distortion caused by multipath delay spread and Doppler shift. Because of the efficient spectrum utilization and the effective anti-multipath capability, the usage of OFDM in HF communication has received extensive attention.
Because of the selective fading caused by multipath and various other factors, OFDM need channel estimation and equalization to compensate the channel characteristic so that the performance loss of demodulation could be minimized. This thesis is focus on these two key techniques for OFDM system used in HF communication, and carries out a detailed study. This thesis is organized as follows:
Chapter one gives an overview of HF communication and OFDM technology, and introduces the researches of the OFDM-based HF communication systems.
Chapter two gives the HF channel model and HF OFDM system model. Through the analyzing of the channel effect in OFDM system, leads to several key technologies need to be solved, which are channel estimation and channel equalization technologies.
In Chapter three, we focus on the channel estimation techniques in the HF OFDM system. Several basic channel estimation algorithms are described in detail. Then from the HF channel characteristics, we design a channel estimation technique which is suitable for HF channel, and discuss the improvement scheme based on this technique.
Chapter four discusses the channel equalization techniques in the HF OFDM system. We design an iterative equalization algorithm for the OFDM systems with short CP. The length of the CP and the channel estimation results on the performance of the proposed algorithm are analyzed by simulation.
Chapter five proposes the iterative equalization techniques with theoretical derivation in the multi-antenna HF OFDM systems, and gives the performance simulation results.
引文
[1]Weinstein, S.; Ebert, P., "Data Transmission by Frequency-Division Multiplexing Using the Discrete Fourier Transform", IEEE Transactions on Communication Technology, Vol. 19, Issue 5, pp.628-634, Oct.1971.
[2]Radio Broadcasting Systems; Digital Audio Broadcasting (DAB) to mobile, portable and fixed receivers [S], European Standard (Telecommunications Series), ETSI EN 300 401, 1995.
[3]Digital Radio Mondiale (DRM), Systems speeification [S], ETSI TS 201 980,2001.
[4]Digital Video Broadcasting (DVB); framing structure, channel coding and modulation for digital terrestrial television (DVB-T) [S], European Standard (Telecommunications Series), ETSI EN 300 744,1997.
[5]王庆,“短波OFDM系统的同步与均衡技术研究[D]”,中国人民解放军信息工程大学,2007.
[6]Coutolleau, M.; Vila, P.; Merel, D.; Pirez, D; Mouy, B., "New studies about a high data rate HF parallel modem", Proceedngs of IEEE Military Commun., Vol.2, pp.381-385, Oct. 1998.
[7]胡中豫,”现代短波通信技术”,国防工业出版社,2003.
[8]沈琪琪；朱德生,“短波通信”,西安电子科技大学出版社,2001.
[9]Watterson, C.C.; Juroshek, J.R.; Bensema, W.D., "EXPERIMENTAL VERIFICATION OF AN IONOSPHERIC CHANNEL MODEL", DTIC Research Report AD0699486, Jul 1969.
[10]Watterson, C.C.; Juroshek, J.R.; Bensema, W.D., " EXPERIMENTAL CONFIRMATION OF AN HF CHANNEL MODEL[J]", IEEE Transactions on Communication Technology, Vol.18, Issue 6, pp.792-803, Dec 1970.
[11]ITU, "Recommendation 520-2 Use of high frequency ionospheric channel simulators", Recommendations and Reports of the CCIR, Vol. Ⅲ, pp.57-58,1986.
[12]Shaver, H.; Tupper, B.; Lomax, J., "Evaluation of a Gaussian HF Channel Model", IEEE Transactions on Communication Technology, Vol.15, Issue 1, pp.79-88, Feb 1967.
[13]David, E.; Franco, A.; Sherman, H.; Shucavage, L., "Correlation Measurements on an HF Transmission Link", IEEE Transactions on Communications Technology, Vol.17, Issue 2, pp.245-256, Apr 1969.
[14]Armel Picquenard, "Radio Wave Propagation", New York, Wiley,1974.
[15]Nissen, C.A.; Bello, P.A., "Measured channel parameters for the disturbed wide-bandwidth HF channel", Radio Sci,38(2), pp.1023-1029, Apr 2003.
[16]Serrat-Fernandez, J.; Delgado-Penin, JA.; Munday, E., "Measurement and Verification of an HF Channel Model", IEE Third Intl. Conf. on HF,1985.
[17]Le Roux, Y.M.; Niberon, M.; Fleury, R.; Menard, J.; Jolivet, J.P.; "HF Channel Modelling and Simulation", Fifth International Conference on Radio Receivers and Associated Systems, pp.72-76, Jul 1990.
[18]Lacaze, B., "Modeling the HF channel with Gaussian random delays", Signal Processing, Vol.64, Issue 2, pp.215-220, Jan 1998.
[19]ITU-R Recommendation, F.1487, "Testing of HF modems with bandwidths of up to about 12kHz using ionospheric channel simulators",2000.
[20]Valenti, M.C.; Woerner, B.D., "Iterative Channel Estimation and Decoding of Pilot Symbol Assisted Turbo Codes Over Flat-Fading Channels", IEEE Journal on Selected Areas in Communiacations, Vol 19, Issue 9, pp.1697-1705, Sep 2001.
[21]Bolcskei, H., "Blind estimation of symbol timing and carrier frequency offset in pulse shaping OFDM systems", IEEE International Conference on Acoustics, Speech, and Signal Processing,1999, Vol 5, pp.2749-2752,1999.
[22]Wei Kang; Champagne B., "Subspace-Based Blind Channel Estimation:Generalization and Performance Analysis", IEEE Transactions on signal processing, Vol 53, Issue 3, pp. 1151-1162, Mar 2005.
[23]Chao-Cheng Tu; Champagne, B., "Subspace-based Blind Channel Estimation for Mimo-OFDM Systems:Reducing the Time Averaging Interval of the Correlation Matrix", IEEE International symposium on personal, Indoor and mobile radio communications, PIMRC 2007, pp.1-5, Sept 2007.
[24]陈建鑫；刘宏立；刘述钢,“基于高阶累积量的信道估计及数字调制识别方法”,计算机系统应用,pp.172-175,2009.
[25]Xiaoqiang Ma; Hisashi Kobayashi; Stuart C. Schwartz, "EM-based channel estimation algorithms for OFDM", EURASIP Journal on Applied Signal Processing, Vol 1, pp. 1460-1477, Jan 2004.
[26]Mazet, L.; Buzenac-Settineri, V.; de Courville, M.; Duhamel, P., "An EM based Semi-blind channel estimation algorithm designed for OFDM systems", Conference Record of the Thirty-Sixth Asilomar Conference on Signals, Systems and Computers,2002, Vol 2, pp.1642-1646, Nov 2002.
[27]Negi, R.; Cioffi, J., "Pilot tone selection for channel estimation in a mobile OFDM system", IEEE Transactions on Consumer Electronics, Vol 44, Issue 3, pp.1122-1128, Aug 1998.
[28]Simeone, O.; Bar-Ness, Y.; Spagnolini, U., "Pilot-based channel estimation for OFDM systems by tracking the delay-subspace", IEEE Transactions on Wireless Communications, Vol 3, Issue 1, pp.315-325, Jan 2004.
[29]Ye Li, "Pilot-symbol-aided channel estimation for OFDM in wireless systems", IEEE Transactions on Vehicular Technology, Vol 49, Issue 4, pp.1207-1215, Jul 2000.
[30]Richad van Nee, "OFDM wireless multimedia communications",2000.
[31]Meng-Han Hsieh; Che-Ho Wei, "Channel estimation for OFDM systems based on comb-type pilot arrangement in frequency selective fading channels", IEEE Transactions on Consumer Electronics, Vol 44, Issue 1, pp.217-225, Feb 1998.
[32]Hoeher, P.; Kaiser, S.; Robertson, P., "Two-dimensional pilot-symbol-aided channel estimation by Wiener filtering",1997 IEEE International Conference on Acoustics, Speech, and Signal Processing,1997, Vol 3, pp.1845-1848, Apr 1997.
[33]Nilsson, R.; Edfors, O.; Sandell, M.; Borjesson, P.O., "An analysis of two-dimensional pilot-symbol assisted modulation for OFDM",1997 IEEE International Conference on Personal Wireless Communications, pp.71-74, Dec 1997.
[34]Yan Sun; Xiaowen Wang; Liu, K.J.R., "A Joint Channel Estimation and Unequal Error Protection Scheme for Video Transmission in OFDM Systems",2002 International Conference on Image Processing, Vol 1, pp.549-552,2002.
[35]Yuping Zhao; Aiping Huang, "A Novel Channel Estimation Method for OFDM Mobile Communication Systems Based on Pilot Signals and Transform-Domain Processing", IEEE 47th Vehicular Technology Conference,1997, Vol 3, pp.2089-2093, May 1997.
[36]Chee Wah Wong; Choi Look Law; Yong Liang Guan, "Channel Estimator for OFDM Systems with 2-Dimensional Filtering in the Transform Domain", IEEE 53rd Vehicular Technology Conference,2001, Vol 1, pp.717-821, May 2001.
[37]Coleri, S.; Ergen, M.; Puri, A.; Bahai, A., "Channel estimation techniques based on pilot arrangement in OFDM systems", IEEE Transactions on Broadcasting, Vol 48, Issue 3, pp. 223-229, Sep 2002.
[38]Edfors, O.; Sandell, M.; van de Beek, J.-J.; Wilson, S.K.; Ola Borjesson, P., "OFDM channel estimation by singular value decomposition", IEEE Transactions on Communications, Vol 2, pp.923-927, Apr 1996.
[39]Edfors, O.; Sandell, M.; van de Beek, J.-J.; Wilson, S.K.; Ola Borjesson, P., "Analysis of DFT-based channel estimators for OFDM", Wireless Personal Communications, pp. 55-70,2000.
[40]van de Beek, J.-J.; Edfors, O.; Sandell, M.; Wilson, S.K.; Borjesson, P.O., "On channel estimation in OFDM systems", IEEE 45th Vehicular Technology Conference,1995, Vol 2, pp.815-819, Jul 1995.
[41]张迪,“基于OFDM的多载波扩频技术的研究”,浙江大学硕士论文,2008.
[42]Morelli, M.; Mengali, U., "A comparison of pilot-aided channel estimation methods for ofdm systems", IEEE Transactions on Signal Processing, Vol 49, Issue 12, pp.3065-3073, Dec 2001.
[43]J. G. Proakis, Ed.,“数字通信(第四版)”,电子工业出版社,2003.
[44]Catherine Douillard; Michel Jezequel; Claude Berrou; Departement Electronique; Annie Picart; Pierre Didier; Alain Glavieux, "Iterative Correction of Intersymbol Intererence: Turbo Equalization", European Transactions on Telecommunications, Vol 6, Issue 5, pp. 507-511, Sep 1995.
[45]Houman Khorram; Gerhard Bauch; Joachim Hagenauer, "Iterative equalization and decoding in mobile communications systems", the Second European Personal Mobile communications Conference,1997.
[46]Laot, C.; Glavieux, A.; Labat, J., "Turbo equalization:adaptive equalization and channel decoding jointly optimized", IEEE Journal on Selected Areas in Communications, Vol 19, Issue 9, pp.1744-1752, Sep 2001.
[47]Ariyavisitakul, S.; Ye Li, "Joint coding and decision feedback equalization for broadband wireless channels",48th IEEE Vehicular Technology Conference,1998, Vol 3, pp. 2256-2261, May 1998.
[48]Laot, C.; Le Bidan, R.; Leroux, D., "Low-Complexity MMSE Turbo Equaliation:A Possible Solution for EDGE", IEEE Transactions on Wireless Communications, Vol 4, Issue 3, pp.965-974, May 2005.
[49]Tuchler, M.; Koetter, R.; Singer, A.C., "Turbo Equalization:Principles and New Results", IEEE Transactions on Communications, Vol 50, Issue 5, pp.754-767, May 2002.
[50]Benvenuto, N.; Tomasin, S., "Iterative design and detection of a DFE in the frequency domain", IEEE Transactions on Communications, Vol 53, Issue 11, pp.1867-1875, Nov 2005.
[51]Melsa, P.J.W.; Younce, R.C.; Rohrs, C.E., "Impulse response shortening for discrete multitone transceivers", IEEE Transactions on Communications, Vol 44, Issue 12, pp. 1662-1672, Dec 1996.
[52]Djokovic, I., "MMSE equalizers for DMT systems with and without crosstalk", Conference Record of the Thirty-First Asilomar Conference on Signals, Systems & Computers, Vol 1, pp.545-549, Nov 1997.
[53]Zhe Chen; Yongyu Chang; Fang Liu; Jing Zhou; Dacheng Yang, "A Turbo FDE Technique for OFDM System without Cyclic Prefix", IEEE 70th Vehicular Technology Conference Fall, pp.1-5, Sept 2009.
[54]Wei-Chieh Huang; Yi-Syun Yang; Chih-Peng Li; Hsueh-Jyh Li, "Superimposed Training for Data Detection and Channel Estimation in OFDM Systems without Cyclic Prefix", IEEE 70th Vehicular Technology Conference Fall, pp.1-5, Sept.2009.
[55]Dukhyun Kim; Stuber, G.L., "Residual ISI Cancellation for OFDM with Applications to HDTV Broadcasting", IEEE Journal on Selected Areas in Communnications, Vol 16, Issue 8, pp.1590-1599, Oct 1998.
[56]Foschini G.J.; Gans M.J., "On Limits of Wireless Communications in a Fading Environment when Using Multiple Antennas", Wireless Personal Communication, Vol 6, pp.311-315,1998.
[57]Alamouti S.M., "A simple transmit diversity technique for wireless communications", IEEE Journal on Selected Areas Communications, Vol 16, Issue 8, pp.1451-1458, Oct 1998.
[58]Gesbert, D.; Shafi, M.; Da-shan Shiu; Smith, P.J.; Naguib, A., "From Theory to Practice:An Overview of MIMO Space-Time Coded Wireless Systems", IEEE Journal on Selected Areas Communications, Vol 21, Issue 3, pp.281-302, Apr 2003.
[59]Alister Burr; Yuriy Zacharov; Hendrik Troeger; etc, "IST-2001-32125 FLOWS D14: Selected MIMO Techniques and their Performance", Jan 2004.
[60]Tarokh, V.; Jafarkhani, H.; Calderbank, A.R., "Space-time block codes from orthogonal designs", IEEE Transactions on Information Theory, Vol 45, Issue 5, pp.1456-1467, Jul 1999.
[61]Tarokh, V.; Jafarkhani, H.; Calderbank, A.R., "Space-time codes for high data rate wireless communication:Performance results", IEEE Journal on Selected Areas Communications, Vol 17, Issue 3, pp.451-460, Mar 1999.
[62]Tarokh, V.; Seshadri, N.; Calderbank, A.R., "Space-time codes for high data rate wireless communication:Performance criterion and code construction", IEEE Transactions on Information Theory, Vol 44, Issue 2, pp.744-765, Mar 1998.
[63]Ye Li, "Simplified Channel Estimation for OFDM System With Multiple Transmit Antennas", IEEE Transactions on Wireless Communications, Vol 1, Issue 1, pp.67-75, Jan 2002.
[2]Radio Broadcasting Systems; Digital Audio Broadcasting (DAB) to mobile, portable and fixed receivers [S], European Standard (Telecommunications Series), ETSI EN 300 401, 1995.
[3]Digital Radio Mondiale (DRM), Systems speeification [S], ETSI TS 201 980,2001.
[4]Digital Video Broadcasting (DVB); framing structure, channel coding and modulation for digital terrestrial television (DVB-T) [S], European Standard (Telecommunications Series), ETSI EN 300 744,1997.
[5]王庆,“短波OFDM系统的同步与均衡技术研究[D]”,中国人民解放军信息工程大学,2007.
[6]Coutolleau, M.; Vila, P.; Merel, D.; Pirez, D; Mouy, B., "New studies about a high data rate HF parallel modem", Proceedngs of IEEE Military Commun., Vol.2, pp.381-385, Oct. 1998.
[7]胡中豫,”现代短波通信技术”,国防工业出版社,2003.
[8]沈琪琪；朱德生,“短波通信”,西安电子科技大学出版社,2001.
[9]Watterson, C.C.; Juroshek, J.R.; Bensema, W.D., "EXPERIMENTAL VERIFICATION OF AN IONOSPHERIC CHANNEL MODEL", DTIC Research Report AD0699486, Jul 1969.
[10]Watterson, C.C.; Juroshek, J.R.; Bensema, W.D., " EXPERIMENTAL CONFIRMATION OF AN HF CHANNEL MODEL[J]", IEEE Transactions on Communication Technology, Vol.18, Issue 6, pp.792-803, Dec 1970.
[11]ITU, "Recommendation 520-2 Use of high frequency ionospheric channel simulators", Recommendations and Reports of the CCIR, Vol. Ⅲ, pp.57-58,1986.
[12]Shaver, H.; Tupper, B.; Lomax, J., "Evaluation of a Gaussian HF Channel Model", IEEE Transactions on Communication Technology, Vol.15, Issue 1, pp.79-88, Feb 1967.
[13]David, E.; Franco, A.; Sherman, H.; Shucavage, L., "Correlation Measurements on an HF Transmission Link", IEEE Transactions on Communications Technology, Vol.17, Issue 2, pp.245-256, Apr 1969.
[14]Armel Picquenard, "Radio Wave Propagation", New York, Wiley,1974.
[15]Nissen, C.A.; Bello, P.A., "Measured channel parameters for the disturbed wide-bandwidth HF channel", Radio Sci,38(2), pp.1023-1029, Apr 2003.
[16]Serrat-Fernandez, J.; Delgado-Penin, JA.; Munday, E., "Measurement and Verification of an HF Channel Model", IEE Third Intl. Conf. on HF,1985.
[17]Le Roux, Y.M.; Niberon, M.; Fleury, R.; Menard, J.; Jolivet, J.P.; "HF Channel Modelling and Simulation", Fifth International Conference on Radio Receivers and Associated Systems, pp.72-76, Jul 1990.
[18]Lacaze, B., "Modeling the HF channel with Gaussian random delays", Signal Processing, Vol.64, Issue 2, pp.215-220, Jan 1998.
[19]ITU-R Recommendation, F.1487, "Testing of HF modems with bandwidths of up to about 12kHz using ionospheric channel simulators",2000.
[20]Valenti, M.C.; Woerner, B.D., "Iterative Channel Estimation and Decoding of Pilot Symbol Assisted Turbo Codes Over Flat-Fading Channels", IEEE Journal on Selected Areas in Communiacations, Vol 19, Issue 9, pp.1697-1705, Sep 2001.
[21]Bolcskei, H., "Blind estimation of symbol timing and carrier frequency offset in pulse shaping OFDM systems", IEEE International Conference on Acoustics, Speech, and Signal Processing,1999, Vol 5, pp.2749-2752,1999.
[22]Wei Kang; Champagne B., "Subspace-Based Blind Channel Estimation:Generalization and Performance Analysis", IEEE Transactions on signal processing, Vol 53, Issue 3, pp. 1151-1162, Mar 2005.
[23]Chao-Cheng Tu; Champagne, B., "Subspace-based Blind Channel Estimation for Mimo-OFDM Systems:Reducing the Time Averaging Interval of the Correlation Matrix", IEEE International symposium on personal, Indoor and mobile radio communications, PIMRC 2007, pp.1-5, Sept 2007.
[24]陈建鑫；刘宏立；刘述钢,“基于高阶累积量的信道估计及数字调制识别方法”,计算机系统应用,pp.172-175,2009.
[25]Xiaoqiang Ma; Hisashi Kobayashi; Stuart C. Schwartz, "EM-based channel estimation algorithms for OFDM", EURASIP Journal on Applied Signal Processing, Vol 1, pp. 1460-1477, Jan 2004.
[26]Mazet, L.; Buzenac-Settineri, V.; de Courville, M.; Duhamel, P., "An EM based Semi-blind channel estimation algorithm designed for OFDM systems", Conference Record of the Thirty-Sixth Asilomar Conference on Signals, Systems and Computers,2002, Vol 2, pp.1642-1646, Nov 2002.
[27]Negi, R.; Cioffi, J., "Pilot tone selection for channel estimation in a mobile OFDM system", IEEE Transactions on Consumer Electronics, Vol 44, Issue 3, pp.1122-1128, Aug 1998.
[28]Simeone, O.; Bar-Ness, Y.; Spagnolini, U., "Pilot-based channel estimation for OFDM systems by tracking the delay-subspace", IEEE Transactions on Wireless Communications, Vol 3, Issue 1, pp.315-325, Jan 2004.
[29]Ye Li, "Pilot-symbol-aided channel estimation for OFDM in wireless systems", IEEE Transactions on Vehicular Technology, Vol 49, Issue 4, pp.1207-1215, Jul 2000.
[30]Richad van Nee, "OFDM wireless multimedia communications",2000.
[31]Meng-Han Hsieh; Che-Ho Wei, "Channel estimation for OFDM systems based on comb-type pilot arrangement in frequency selective fading channels", IEEE Transactions on Consumer Electronics, Vol 44, Issue 1, pp.217-225, Feb 1998.
[32]Hoeher, P.; Kaiser, S.; Robertson, P., "Two-dimensional pilot-symbol-aided channel estimation by Wiener filtering",1997 IEEE International Conference on Acoustics, Speech, and Signal Processing,1997, Vol 3, pp.1845-1848, Apr 1997.
[33]Nilsson, R.; Edfors, O.; Sandell, M.; Borjesson, P.O., "An analysis of two-dimensional pilot-symbol assisted modulation for OFDM",1997 IEEE International Conference on Personal Wireless Communications, pp.71-74, Dec 1997.
[34]Yan Sun; Xiaowen Wang; Liu, K.J.R., "A Joint Channel Estimation and Unequal Error Protection Scheme for Video Transmission in OFDM Systems",2002 International Conference on Image Processing, Vol 1, pp.549-552,2002.
[35]Yuping Zhao; Aiping Huang, "A Novel Channel Estimation Method for OFDM Mobile Communication Systems Based on Pilot Signals and Transform-Domain Processing", IEEE 47th Vehicular Technology Conference,1997, Vol 3, pp.2089-2093, May 1997.
[36]Chee Wah Wong; Choi Look Law; Yong Liang Guan, "Channel Estimator for OFDM Systems with 2-Dimensional Filtering in the Transform Domain", IEEE 53rd Vehicular Technology Conference,2001, Vol 1, pp.717-821, May 2001.
[37]Coleri, S.; Ergen, M.; Puri, A.; Bahai, A., "Channel estimation techniques based on pilot arrangement in OFDM systems", IEEE Transactions on Broadcasting, Vol 48, Issue 3, pp. 223-229, Sep 2002.
[38]Edfors, O.; Sandell, M.; van de Beek, J.-J.; Wilson, S.K.; Ola Borjesson, P., "OFDM channel estimation by singular value decomposition", IEEE Transactions on Communications, Vol 2, pp.923-927, Apr 1996.
[39]Edfors, O.; Sandell, M.; van de Beek, J.-J.; Wilson, S.K.; Ola Borjesson, P., "Analysis of DFT-based channel estimators for OFDM", Wireless Personal Communications, pp. 55-70,2000.
[40]van de Beek, J.-J.; Edfors, O.; Sandell, M.; Wilson, S.K.; Borjesson, P.O., "On channel estimation in OFDM systems", IEEE 45th Vehicular Technology Conference,1995, Vol 2, pp.815-819, Jul 1995.
[41]张迪,“基于OFDM的多载波扩频技术的研究”,浙江大学硕士论文,2008.
[42]Morelli, M.; Mengali, U., "A comparison of pilot-aided channel estimation methods for ofdm systems", IEEE Transactions on Signal Processing, Vol 49, Issue 12, pp.3065-3073, Dec 2001.
[43]J. G. Proakis, Ed.,“数字通信(第四版)”,电子工业出版社,2003.
[44]Catherine Douillard; Michel Jezequel; Claude Berrou; Departement Electronique; Annie Picart; Pierre Didier; Alain Glavieux, "Iterative Correction of Intersymbol Intererence: Turbo Equalization", European Transactions on Telecommunications, Vol 6, Issue 5, pp. 507-511, Sep 1995.
[45]Houman Khorram; Gerhard Bauch; Joachim Hagenauer, "Iterative equalization and decoding in mobile communications systems", the Second European Personal Mobile communications Conference,1997.
[46]Laot, C.; Glavieux, A.; Labat, J., "Turbo equalization:adaptive equalization and channel decoding jointly optimized", IEEE Journal on Selected Areas in Communications, Vol 19, Issue 9, pp.1744-1752, Sep 2001.
[47]Ariyavisitakul, S.; Ye Li, "Joint coding and decision feedback equalization for broadband wireless channels",48th IEEE Vehicular Technology Conference,1998, Vol 3, pp. 2256-2261, May 1998.
[48]Laot, C.; Le Bidan, R.; Leroux, D., "Low-Complexity MMSE Turbo Equaliation:A Possible Solution for EDGE", IEEE Transactions on Wireless Communications, Vol 4, Issue 3, pp.965-974, May 2005.
[49]Tuchler, M.; Koetter, R.; Singer, A.C., "Turbo Equalization:Principles and New Results", IEEE Transactions on Communications, Vol 50, Issue 5, pp.754-767, May 2002.
[50]Benvenuto, N.; Tomasin, S., "Iterative design and detection of a DFE in the frequency domain", IEEE Transactions on Communications, Vol 53, Issue 11, pp.1867-1875, Nov 2005.
[51]Melsa, P.J.W.; Younce, R.C.; Rohrs, C.E., "Impulse response shortening for discrete multitone transceivers", IEEE Transactions on Communications, Vol 44, Issue 12, pp. 1662-1672, Dec 1996.
[52]Djokovic, I., "MMSE equalizers for DMT systems with and without crosstalk", Conference Record of the Thirty-First Asilomar Conference on Signals, Systems & Computers, Vol 1, pp.545-549, Nov 1997.
[53]Zhe Chen; Yongyu Chang; Fang Liu; Jing Zhou; Dacheng Yang, "A Turbo FDE Technique for OFDM System without Cyclic Prefix", IEEE 70th Vehicular Technology Conference Fall, pp.1-5, Sept 2009.
[54]Wei-Chieh Huang; Yi-Syun Yang; Chih-Peng Li; Hsueh-Jyh Li, "Superimposed Training for Data Detection and Channel Estimation in OFDM Systems without Cyclic Prefix", IEEE 70th Vehicular Technology Conference Fall, pp.1-5, Sept.2009.
[55]Dukhyun Kim; Stuber, G.L., "Residual ISI Cancellation for OFDM with Applications to HDTV Broadcasting", IEEE Journal on Selected Areas in Communnications, Vol 16, Issue 8, pp.1590-1599, Oct 1998.
[56]Foschini G.J.; Gans M.J., "On Limits of Wireless Communications in a Fading Environment when Using Multiple Antennas", Wireless Personal Communication, Vol 6, pp.311-315,1998.
[57]Alamouti S.M., "A simple transmit diversity technique for wireless communications", IEEE Journal on Selected Areas Communications, Vol 16, Issue 8, pp.1451-1458, Oct 1998.
[58]Gesbert, D.; Shafi, M.; Da-shan Shiu; Smith, P.J.; Naguib, A., "From Theory to Practice:An Overview of MIMO Space-Time Coded Wireless Systems", IEEE Journal on Selected Areas Communications, Vol 21, Issue 3, pp.281-302, Apr 2003.
[59]Alister Burr; Yuriy Zacharov; Hendrik Troeger; etc, "IST-2001-32125 FLOWS D14: Selected MIMO Techniques and their Performance", Jan 2004.
[60]Tarokh, V.; Jafarkhani, H.; Calderbank, A.R., "Space-time block codes from orthogonal designs", IEEE Transactions on Information Theory, Vol 45, Issue 5, pp.1456-1467, Jul 1999.
[61]Tarokh, V.; Jafarkhani, H.; Calderbank, A.R., "Space-time codes for high data rate wireless communication:Performance results", IEEE Journal on Selected Areas Communications, Vol 17, Issue 3, pp.451-460, Mar 1999.
[62]Tarokh, V.; Seshadri, N.; Calderbank, A.R., "Space-time codes for high data rate wireless communication:Performance criterion and code construction", IEEE Transactions on Information Theory, Vol 44, Issue 2, pp.744-765, Mar 1998.
[63]Ye Li, "Simplified Channel Estimation for OFDM System With Multiple Transmit Antennas", IEEE Transactions on Wireless Communications, Vol 1, Issue 1, pp.67-75, Jan 2002.