基于有限反馈的LTE-A下行系统码本设计及关键算法研究
摘要
随着第四代移动通信技术的兴起,学术界对LTE-Advanced的研究也不断增长,近年来,基于有限反馈的MIMO增强技术受到很大的关注。3GPP协议指出LTE-A系统下行峰值速率目标为1Gbps。而如此高的下行峰值速率要求LTE-A下行系统的天线数目必须扩展到8根,但目前3GPP LTE Release 8标准的码本只有4天线配置,因此有必要为LTE-A系统重新设计8天线码本。本文提出了一种适用于LTE-A下行系统的8天线码本方案。该方案使用酉矩阵和旋转矩阵,结合DFT码本以及LTE Release 8码本,不仅保持后向兼容性,而且继承了LTE Release 8码本的优良特性。理论分析和模拟仿真证实了本方法的有效性。
本文首先介绍了有关码本技术背景,并结合码本介绍了有限反馈在无线通信系统中的应用。这些应用有协方差量化、波束赋形、空间复用线性预编码等。其次基于LTERelease 8版本的物理层协议,进行了链路级仿真平台PDSCH发送模块的搭建工作。接着对包括码本设计在内的预编码模型进行了介绍。然后根据具有代表性的LTERelease 8码本和三星码本,对大家比较公认的码本设计原则进行了说明。最后介绍本文提出的码本算法的主要思想：结合8x8维度的DFT码本在非相关信道的优势,在LTERelease 8码本设计的基础上,特别针对双极化信道状态矩阵的块对角化特征,设计了对应的旋转块对角化矩阵算法来生成LTE-A码本。这样设计的优点：继承LTE Release8码本的恒模特性、8-psk有限字符表特性、嵌套特性等优良特性,而且具有LTE-A系统的后向兼容性,特别是在双极化信道下本文设计的码本性能表现优秀。对具有代表性的LTE Release 8码本和三星码本进行理论反馈开销和复杂度分析,并在双极化信道、非相关信道和相关信道环境进行仿真,仿真结果进一步证明了本文提出的码本算法性能优良,能够有效提高系统的吞吐量和降低系统误块率,所以是一种适用于LTE-Advanced高效的码本设计方案。
With the rising of the fourth generation of mobile communication technology, academic research on the LTE-Advanced is also growing. In recent years, MIMO enhancements technology based on the limited feedback is concerned.3GPP protocol 36.913 points out that LTE-A system should target a downlink peak data rate of 1 Gbps, so it requires the number of antenna must be extended to eight in downlink transmission system of LTE-A. At present, the codebook of 3GPP LTE Release 8 standard codebook only supports four antennas, therefore, the design and research for a codebook based on limited feedback supporting eight antennas and its key algorithm is necessary in LTE-A downlink system. This thesis proposes a codebook method designed for eight antennas in dowenlink system of LTE-A. The proposed method uses the rotation of the DFT-based codebook, and reuses the LTE Release 8 codebook, not only to maintain backward compatibility, but also inherit the good characteristics of LTE Release 8 codebook. Theoretical analysis and computer simulation confirm the validity of the method.
Firstly this thesis describes the technical background about the codebook, and describes the application about codebook of limited feedback in wireless communication system. The application contains quantitative covariance, beamforming, spatial multiplexing with linear precoding. Secondly, based on the LTE Release 8 of the physical layer protocols, part of PDSCH sending module of the link level simulation platform is built. Then including codebook, precoding model is described. According LTE codebook and Samsung codebook, the recognized design principles of codebook are described. Finally, we introduce our idea of the proposed codebook:with combining the advantages of 8x8 DFT codebook in non-correlated channel, based on LTE Release 8 codebook, we design of the corresponding rotation block diagonalization matrix for dual-polarized channel to generate the LTE-A codebook. This has the advantages that it can not only maintain the backward compatibility of LTE-A, but also inherit many good features of the LTE codebook. We analysis the feedback overhead and the complexity of representative LTE Release 8 codebook and Samsung codebook in theoretical, and simulate them in the correlated channel, non-correlated channel and dual-polarized channel respectively. The simulation results show that the performance of proposed codebook algorithm are excellent, it can effectively reduce the block error rate, and also improve the system throughput, so that it is a suitable design and efficient codebook for LTE-A system.
本文首先介绍了有关码本技术背景,并结合码本介绍了有限反馈在无线通信系统中的应用。这些应用有协方差量化、波束赋形、空间复用线性预编码等。其次基于LTERelease 8版本的物理层协议,进行了链路级仿真平台PDSCH发送模块的搭建工作。接着对包括码本设计在内的预编码模型进行了介绍。然后根据具有代表性的LTERelease 8码本和三星码本,对大家比较公认的码本设计原则进行了说明。最后介绍本文提出的码本算法的主要思想：结合8x8维度的DFT码本在非相关信道的优势,在LTERelease 8码本设计的基础上,特别针对双极化信道状态矩阵的块对角化特征,设计了对应的旋转块对角化矩阵算法来生成LTE-A码本。这样设计的优点：继承LTE Release8码本的恒模特性、8-psk有限字符表特性、嵌套特性等优良特性,而且具有LTE-A系统的后向兼容性,特别是在双极化信道下本文设计的码本性能表现优秀。对具有代表性的LTE Release 8码本和三星码本进行理论反馈开销和复杂度分析,并在双极化信道、非相关信道和相关信道环境进行仿真,仿真结果进一步证明了本文提出的码本算法性能优良,能够有效提高系统的吞吐量和降低系统误块率,所以是一种适用于LTE-Advanced高效的码本设计方案。
With the rising of the fourth generation of mobile communication technology, academic research on the LTE-Advanced is also growing. In recent years, MIMO enhancements technology based on the limited feedback is concerned.3GPP protocol 36.913 points out that LTE-A system should target a downlink peak data rate of 1 Gbps, so it requires the number of antenna must be extended to eight in downlink transmission system of LTE-A. At present, the codebook of 3GPP LTE Release 8 standard codebook only supports four antennas, therefore, the design and research for a codebook based on limited feedback supporting eight antennas and its key algorithm is necessary in LTE-A downlink system. This thesis proposes a codebook method designed for eight antennas in dowenlink system of LTE-A. The proposed method uses the rotation of the DFT-based codebook, and reuses the LTE Release 8 codebook, not only to maintain backward compatibility, but also inherit the good characteristics of LTE Release 8 codebook. Theoretical analysis and computer simulation confirm the validity of the method.
Firstly this thesis describes the technical background about the codebook, and describes the application about codebook of limited feedback in wireless communication system. The application contains quantitative covariance, beamforming, spatial multiplexing with linear precoding. Secondly, based on the LTE Release 8 of the physical layer protocols, part of PDSCH sending module of the link level simulation platform is built. Then including codebook, precoding model is described. According LTE codebook and Samsung codebook, the recognized design principles of codebook are described. Finally, we introduce our idea of the proposed codebook:with combining the advantages of 8x8 DFT codebook in non-correlated channel, based on LTE Release 8 codebook, we design of the corresponding rotation block diagonalization matrix for dual-polarized channel to generate the LTE-A codebook. This has the advantages that it can not only maintain the backward compatibility of LTE-A, but also inherit many good features of the LTE codebook. We analysis the feedback overhead and the complexity of representative LTE Release 8 codebook and Samsung codebook in theoretical, and simulate them in the correlated channel, non-correlated channel and dual-polarized channel respectively. The simulation results show that the performance of proposed codebook algorithm are excellent, it can effectively reduce the block error rate, and also improve the system throughput, so that it is a suitable design and efficient codebook for LTE-A system.
引文
[1]3GPP TR 36.913 v10.0.0,3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Requirements for further advancements for Evolved Universal Terrestrial Radio Access (E-UTRA),2011年4月
[2]David J.Love, Robert W.Heath Jr, Vincent K.N.Lau, David Gesbert, Bhaskar D.Rao, Matthew Andrews, "An overview of limited feedback in wireless communication systems",2008
[3]吴敏、沈超、裘正定,时间相干信道下波束赋形系统的有限反馈方法,电子与信息学报,2009年10月
[4]A.Paulraj, R.Nabar, and D.Gore, Introduction to Space-Time Wireless Communications, Cambridge Univ.Press,2003
[5]R.S.Blum, " MIMO with limited feedback of channel state information, " inProc.IEEE Int.Conf.Acoust, Speech and Sig.Proc,vol.4,April 2003,pp.89-92
[6]V.Lau, Y.Liu, and T.-A.Chen, "On the design of MIMO block- fading channels with feedback-link capacity constraint", IEEE Trans.Commun.,vol.52,no.l,pp.62-70,Jan.2004
[7]A.D.Dabbagh and D.J.Love, "Feedback rate-capacity loss tradeoff for limited feedback MIMO systems," IEEE Trans.Inform.Theory,vol.52,no.5,pp.2190-2202,May 2006
[8]H.Zhang, S.Wei, G.Ananthaswamy, and D.L.Goeckel, "Adaptive signaling based on statistical characterizations of outdated feedback in wireless communications", Proc. IEEE,vol.85,no.12, pp.23372353, Dec.2007
[9]3GPP TS 36.211 V10.0.0,Evolved Universal Terrestrial Radio Access (E-UTRA):Physical Channels and Modulation,2010年12月
[10]Samsung, R1-091246, "Codebook Design for 8-Tx Transmission in LTE-A",3GPP TSG RAN WG1 Meetting #56b,2009
[11]J. Hayes, "Adaptive feedback communications," IEEE Trans. Commun.,vol.16, no.1, pp.29-34, Feb.1968
[12]J.Schalkwijk, "Coding scheme for additive noise channels with feedback-Part Ⅱ:Band-limited signals," IEEE Trans. Inform. Theory, vol.12, pp.183-189, April 1966
[13]J.Schalkwijk and T.Kailath, "A coding scheme for additive noise channels with feedback-Part Ⅰ:No bandwidth constraint," IEEE Trans.Inform.Theory, vol.12, pp.172-183, April 1966
[14]GL.Turin, "Signal design for sequential detection systems with feedback," IEEE Trans. Inform.Theory, vol.11, pp.401-408, July 1965
[15]G.Turin, "Comparison of sequential and nonsequential detection systems with uncertainty feedback," IEEE Trans. Inform. Theory, vol.12, pp.5-8, Jan.1966
[16]A.Goldsmith, S.A.Jafar, N.Jindal, and S.Vishwanath, "Capacity limits of MIMO channels," IEEE J. Select. Areas Commun.,vol.21, no.5, pp.684-702, June 2003
[17]M.Skoglund and GJongren, "On the capacity of a multiple-antenna communication link with channel side information," IEEE J. Select. Areas Commun., vol.21, no.3, pp.395-405, April 2003
[18]B Mondal, "Channel adaptive quantization for limited feedback MIMO beamforming systems," IEEE Trans. Signal Processing, vol.54, no.12, pp.4717-4729, Dec.2006
[19]R.Samanta and R.W.Heath Jr., "Codebook Adaptation for Quantized MIMO Beamforming Systems," in Proc.IEEE Asilomar Conf. on Signals, Systems, and Comp.,Oct./Nov.2005, pp. 376-380
[20]D.J.Love and R.W.Heath,Jr., "Equal gain transmission in multiple-input multiple-output wireless systems," IEEE Trans.Com-mun.,vol.51, no.7, pp.1102-1110,July 2003
[21]Y.Li, N.B.Mehta, A.F.Molisch, and J.Zhang, "Optimal signaling and selection verification for single transmit-antenna selection," IEEE Trans.Commun., vol.55, no.4, pp.778-789, April 2007
[22]A.Narula, M.J.Lopez, M.D.Trott, and G.W.Wornell, "Efficient use of side information in mulitiple-antenna data transmission over fading channels," IEEE J. Select. Areas Commun., vol.16, no.8, pp.1423-1436, Oct.1998
[23]R.W.Heath, Jr. and A.Paulraj, "A simple scheme for transmit diversity using partial channel feedback," in Proc. IEEE Asilomar Conf. on Signals, Systems, and Comp., vol.2, Nov.1998, pp.1073-1078
[24]S.Thoen, L.Vander Perre, B.Gyselinckx, and M.Engels, "Perfor-mance analysis of combined transmit-SC/receive-MRC," IEEE Trans. Commun., vol.49, no.1, pp.5-8, Jan.2001
[25]D.J.Love, R.W.Heath Jr., and T.Strohmer, "Grassmannian beamforming for multiple-input multiple-output wireless systems," IEEE Trans.Inform. Theory,vol.49, no.10,pp.2735-2747, Oct. 2003
[26]T.Strohmer and R.W.Heath.Jr., "Grassmannian frames with applications to coding and communications," Applied and Computational Harmonic Analysis, vol.14, no.3, pp.57-275, May 2003
[27]P.Xia, S.Zhou, and GB.Giannakis, "Achieving the Welch bound with difference sets," IEEE Trans. Inform. Theory, vol.51, no.5, pp.1900-1907, May 2005
[28]J.C.Roh and B.D.Rao, "Transmit beamforming in multiple-antennasystems with finite rate feedback:A VQ-based approach," IEEE Trans.Inform. Theory, vol.52, no.3, pp.1101-1112, March 2006
[29]J.Zheng and B.D.Rao, "Analysis of multiple antenna systems with finite-rate channel information feedback over spatially correlated fading channels," IEEE Trans.Signal Processing, vol.55, no.9, pp.4612-4626, Sept.2007
[30]3GPP TS 36.212 V10.0.0,Evolved Universal Terrestrial Radio Access (E-UTRA):Multiplexing and channel coding,2010年12月
[31]3GPP TS 36.213 V10.0.1,Evolved Universal Terrestrial Radio Access (E-UTRA):Physical layer procedures,2010年12月
[32]王海洋,MIMO系统中的有限反馈技术研究,浙江大学,2008
[33]沈嘉、索士强等,3GPP长期演进(LTE)技术原理与系统设计,人民邮电出版社,pp.43-124,2008年11月
[34]Stefania Sesia等,LTE-UMTS长期演进理论与实践,pp.187-216,2009年12月
[35]D.J.Love, R.W.Heath, and T.Strohmer, "Grassmannian Beamforming for Multiple-Input Multiple-Output Wireless Systems," IEEE Trans.Inform.Theory, vol.49, no.10,pp.2735-2747, Oct. 2003
[36]B.Clerckx, Y.X.Zhou, and S.Kim, "Practical codebook design for limited feedback spatial multiplexing," in Proc. IEEE Int. Conf. on Commun., pp.3982-3987. May 2008
[37]V.Lau, Y.Liu and T.-A.Chen, "Capacity of memoryless channels and block-fading channels with designable cardinality-constrained channel state feedback, " IEEE Trans. Inform. Theory, vol.50,no.9, pp.2038 2049, Sept.2004
[38]Samsung, R1-090105, Codebook based Precoding for 8 Tx Transmission in LTE-A,3GPP TSG RAN WG1 Meetting #55b,2009
[39]Samsung, R1-091079,Codebook Design for 8 Tx Transmission in LTE-A,3GPP TSG RAN WG1 Meetting #56,2009
[40]Randall T.Becker, "3GPP LTE的预编码和空间多路复用MIMO技术”,电子产品世界,2009
[41]张萌,LTE系统中MIMO预编码技术研究,西南交通大学,2010
[42]方亮,LTE预编码技术,北京邮电大学,2010
[43]李斌,移动通信中MIMO预编码技术研究,北京邮电大学,2010
[44]吕铁军,“多天线MIMO预编码传输技术的研究”,北京邮电大学,2009
[45]黎威,MIMO系统中天线选择技术的研究,武汉理工大学,2009
[46]顿玉成、杜栓义,SCM与SCME信道模型比较,电子科技,2008
[47]Marvell, R1-090388, "Precoding options for 8-Tx antennas in LTE-A DL",3GPP TSG RAN WG1 Meetting #56,2009
[48]刘美,LTE-Advanced系统中Relay技术及其系统性能研究,武汉理工大学,2010
[49]金鑫,下行MIMO系统无线资源管理关键技术研究,中国科学院计算技术研究所,2010
[50]波尔拉,空时无线通信导论,清华大学出版社,pp.36-39,2005
[51]金鑫,田霖,吴志龙等,重用LTE码本的八天线码本设计方法,中国科学院计算技术研究所,专利号CN201010293253.4,2010
[52]吴志龙,田霖,杨育波,庞迪,金鑫等,一种两级码本的构造与信道反馈方法,中国科学院计算技术研究所,专利号CN201010249761.2,2010
[2]David J.Love, Robert W.Heath Jr, Vincent K.N.Lau, David Gesbert, Bhaskar D.Rao, Matthew Andrews, "An overview of limited feedback in wireless communication systems",2008
[3]吴敏、沈超、裘正定,时间相干信道下波束赋形系统的有限反馈方法,电子与信息学报,2009年10月
[4]A.Paulraj, R.Nabar, and D.Gore, Introduction to Space-Time Wireless Communications, Cambridge Univ.Press,2003
[5]R.S.Blum, " MIMO with limited feedback of channel state information, " inProc.IEEE Int.Conf.Acoust, Speech and Sig.Proc,vol.4,April 2003,pp.89-92
[6]V.Lau, Y.Liu, and T.-A.Chen, "On the design of MIMO block- fading channels with feedback-link capacity constraint", IEEE Trans.Commun.,vol.52,no.l,pp.62-70,Jan.2004
[7]A.D.Dabbagh and D.J.Love, "Feedback rate-capacity loss tradeoff for limited feedback MIMO systems," IEEE Trans.Inform.Theory,vol.52,no.5,pp.2190-2202,May 2006
[8]H.Zhang, S.Wei, G.Ananthaswamy, and D.L.Goeckel, "Adaptive signaling based on statistical characterizations of outdated feedback in wireless communications", Proc. IEEE,vol.85,no.12, pp.23372353, Dec.2007
[9]3GPP TS 36.211 V10.0.0,Evolved Universal Terrestrial Radio Access (E-UTRA):Physical Channels and Modulation,2010年12月
[10]Samsung, R1-091246, "Codebook Design for 8-Tx Transmission in LTE-A",3GPP TSG RAN WG1 Meetting #56b,2009
[11]J. Hayes, "Adaptive feedback communications," IEEE Trans. Commun.,vol.16, no.1, pp.29-34, Feb.1968
[12]J.Schalkwijk, "Coding scheme for additive noise channels with feedback-Part Ⅱ:Band-limited signals," IEEE Trans. Inform. Theory, vol.12, pp.183-189, April 1966
[13]J.Schalkwijk and T.Kailath, "A coding scheme for additive noise channels with feedback-Part Ⅰ:No bandwidth constraint," IEEE Trans.Inform.Theory, vol.12, pp.172-183, April 1966
[14]GL.Turin, "Signal design for sequential detection systems with feedback," IEEE Trans. Inform.Theory, vol.11, pp.401-408, July 1965
[15]G.Turin, "Comparison of sequential and nonsequential detection systems with uncertainty feedback," IEEE Trans. Inform. Theory, vol.12, pp.5-8, Jan.1966
[16]A.Goldsmith, S.A.Jafar, N.Jindal, and S.Vishwanath, "Capacity limits of MIMO channels," IEEE J. Select. Areas Commun.,vol.21, no.5, pp.684-702, June 2003
[17]M.Skoglund and GJongren, "On the capacity of a multiple-antenna communication link with channel side information," IEEE J. Select. Areas Commun., vol.21, no.3, pp.395-405, April 2003
[18]B Mondal, "Channel adaptive quantization for limited feedback MIMO beamforming systems," IEEE Trans. Signal Processing, vol.54, no.12, pp.4717-4729, Dec.2006
[19]R.Samanta and R.W.Heath Jr., "Codebook Adaptation for Quantized MIMO Beamforming Systems," in Proc.IEEE Asilomar Conf. on Signals, Systems, and Comp.,Oct./Nov.2005, pp. 376-380
[20]D.J.Love and R.W.Heath,Jr., "Equal gain transmission in multiple-input multiple-output wireless systems," IEEE Trans.Com-mun.,vol.51, no.7, pp.1102-1110,July 2003
[21]Y.Li, N.B.Mehta, A.F.Molisch, and J.Zhang, "Optimal signaling and selection verification for single transmit-antenna selection," IEEE Trans.Commun., vol.55, no.4, pp.778-789, April 2007
[22]A.Narula, M.J.Lopez, M.D.Trott, and G.W.Wornell, "Efficient use of side information in mulitiple-antenna data transmission over fading channels," IEEE J. Select. Areas Commun., vol.16, no.8, pp.1423-1436, Oct.1998
[23]R.W.Heath, Jr. and A.Paulraj, "A simple scheme for transmit diversity using partial channel feedback," in Proc. IEEE Asilomar Conf. on Signals, Systems, and Comp., vol.2, Nov.1998, pp.1073-1078
[24]S.Thoen, L.Vander Perre, B.Gyselinckx, and M.Engels, "Perfor-mance analysis of combined transmit-SC/receive-MRC," IEEE Trans. Commun., vol.49, no.1, pp.5-8, Jan.2001
[25]D.J.Love, R.W.Heath Jr., and T.Strohmer, "Grassmannian beamforming for multiple-input multiple-output wireless systems," IEEE Trans.Inform. Theory,vol.49, no.10,pp.2735-2747, Oct. 2003
[26]T.Strohmer and R.W.Heath.Jr., "Grassmannian frames with applications to coding and communications," Applied and Computational Harmonic Analysis, vol.14, no.3, pp.57-275, May 2003
[27]P.Xia, S.Zhou, and GB.Giannakis, "Achieving the Welch bound with difference sets," IEEE Trans. Inform. Theory, vol.51, no.5, pp.1900-1907, May 2005
[28]J.C.Roh and B.D.Rao, "Transmit beamforming in multiple-antennasystems with finite rate feedback:A VQ-based approach," IEEE Trans.Inform. Theory, vol.52, no.3, pp.1101-1112, March 2006
[29]J.Zheng and B.D.Rao, "Analysis of multiple antenna systems with finite-rate channel information feedback over spatially correlated fading channels," IEEE Trans.Signal Processing, vol.55, no.9, pp.4612-4626, Sept.2007
[30]3GPP TS 36.212 V10.0.0,Evolved Universal Terrestrial Radio Access (E-UTRA):Multiplexing and channel coding,2010年12月
[31]3GPP TS 36.213 V10.0.1,Evolved Universal Terrestrial Radio Access (E-UTRA):Physical layer procedures,2010年12月
[32]王海洋,MIMO系统中的有限反馈技术研究,浙江大学,2008
[33]沈嘉、索士强等,3GPP长期演进(LTE)技术原理与系统设计,人民邮电出版社,pp.43-124,2008年11月
[34]Stefania Sesia等,LTE-UMTS长期演进理论与实践,pp.187-216,2009年12月
[35]D.J.Love, R.W.Heath, and T.Strohmer, "Grassmannian Beamforming for Multiple-Input Multiple-Output Wireless Systems," IEEE Trans.Inform.Theory, vol.49, no.10,pp.2735-2747, Oct. 2003
[36]B.Clerckx, Y.X.Zhou, and S.Kim, "Practical codebook design for limited feedback spatial multiplexing," in Proc. IEEE Int. Conf. on Commun., pp.3982-3987. May 2008
[37]V.Lau, Y.Liu and T.-A.Chen, "Capacity of memoryless channels and block-fading channels with designable cardinality-constrained channel state feedback, " IEEE Trans. Inform. Theory, vol.50,no.9, pp.2038 2049, Sept.2004
[38]Samsung, R1-090105, Codebook based Precoding for 8 Tx Transmission in LTE-A,3GPP TSG RAN WG1 Meetting #55b,2009
[39]Samsung, R1-091079,Codebook Design for 8 Tx Transmission in LTE-A,3GPP TSG RAN WG1 Meetting #56,2009
[40]Randall T.Becker, "3GPP LTE的预编码和空间多路复用MIMO技术”,电子产品世界,2009
[41]张萌,LTE系统中MIMO预编码技术研究,西南交通大学,2010
[42]方亮,LTE预编码技术,北京邮电大学,2010
[43]李斌,移动通信中MIMO预编码技术研究,北京邮电大学,2010
[44]吕铁军,“多天线MIMO预编码传输技术的研究”,北京邮电大学,2009
[45]黎威,MIMO系统中天线选择技术的研究,武汉理工大学,2009
[46]顿玉成、杜栓义,SCM与SCME信道模型比较,电子科技,2008
[47]Marvell, R1-090388, "Precoding options for 8-Tx antennas in LTE-A DL",3GPP TSG RAN WG1 Meetting #56,2009
[48]刘美,LTE-Advanced系统中Relay技术及其系统性能研究,武汉理工大学,2010
[49]金鑫,下行MIMO系统无线资源管理关键技术研究,中国科学院计算技术研究所,2010
[50]波尔拉,空时无线通信导论,清华大学出版社,pp.36-39,2005
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