Turbo均衡中的符号方差反馈均衡器

武岩波; 房小芳; 朱敏

doi:10.11999/JEIT150825

Turbo均衡中的符号方差反馈均衡器

doi: 10.11999/JEIT150825

基金项目:

国家自然科学基金(61471351)，国家863计划(2009AA 093301)

计量
- 文章访问数: 1646
- HTML全文浏览量: 232
- PDF下载量: 408
- 被引次数: 0
出版历程
- 收稿日期: 2015-07-09
- 修回日期: 2015-12-08
- 刊出日期: 2016-03-19

Symbol-variance Feedback Equalizer for Turbo Equalization

Funds:

The National Natural Science Foundation of China (61471351), The National 863 Program of China (2009AA 093301)

摘要

摘要: 为了降低Turbo均衡中均衡器的复杂度，该文提出了符号方差反馈均衡算法(SVFE)。该算法是对精确的线性最小均方误差估计值(LMMSE)进行Taylor展开得到的。在该算法中，先利用时不变均衡器得到初步符号估计值，再根据先验符号方差对估计值加权，最后进行时不变滤波得到更佳的符号估计值。由于用到了时变的先验符号方差信息，其性能更接近精确的LMMSE均衡器。将所提算法用于Proakis C信道下的Turbo均衡处理，和时不变均衡算法进行仿真对比，所提算法将信噪比损失从0.83 dB降到了0.17 dB，并且仍可通过快速傅里叶变换降低为对数复杂度。
- Turbo均衡 /
- 软输入软输出均衡 /
- 最小均方误差线性均衡器
Abstract: A novel Symbol-Variance Feedback Equalizer (SVEF) algorithm is proposed to reduce the computational complexity of the equalizer in Turbo equalization. The derivation of the algorithm is based on the Taylor expansion of the Linear Minimum Mean Squared Error (LMMSE) estimation function. In the proposed scheme, the initial estimates are obtained from the time-invariant equalizer, then the estimates are weighted by the a priori symbol variances and finally filtered by a time-invariant filter to obtain better estimates. As the time-variant a priori symbol variances are utilized, the performance of the proposed equalizer is much closer to that of the exact MMSE linear equalizer. Simulation results show that the Signal-to-Noise Ratio (SNR) loss of the proposed scheme in Proakis C channel is reduced to 0.17 dB from 0.83 dB compared to the various time-invariant MMSE Turbo equalization, and its computational complexity can be reduced to logarithmical order by implementation based on the fast Fourier transform.
- Turbo equalization /
- Soft-Input Soft-Output (SISO) equalizer /
- Minimum Mean Squared Error (MMSE) linear equalizer

HTML全文

参考文献(26)

DOUILLARD C, JEZEQUEL M, BERROU C, et al. Iterative correction of intersymbol interference: Turbo- equalization[J]. European Transactions on Telecommunications and Related Technologies, 1995, 6(5): 507-511. doi: 10.1002/ett.4460060506.

TUCHLER M, KOETTER R, and SINGER A C. Turbo equalization: principles and new results[J]. IEEE Transactions on Communications, 2002, 50(5): 754-767. doi: 10.1109/TCOMM.2002.1006557.

TUCHLER M, SINGER A C, and KOETTER R. Minimum mean squared error equalization using a priori information[J]. IEEE Transactions on Signal Processing, 2002, 50(3): 673-683. doi: 10.1109/78.984761.

LOPES R R. Iterative estimation, equalization and decoding[D]. [Ph.D. dissertation], Georgia Institute of Technology, 2003.

TUCHLER M and SINGER A C. Turbo equalization: An overview[J]. IEEE Transactions on Information Theory, 2011, 57(2): 920-952. doi: 10.1109/TIT.2010.2096033.

GUO Q and HUANG D. Concise representation for the soft-in soft-out LMMSE detector[J]. IEEE Communications Letters, 2011, 15(5): 566-568. doi: 10.1109/LCOMM.2011. 032811.102073.

LAOT C, GLAVIEUX A, and LABAT J. Turbo equalization: adaptive equalization and channel decoding jointly optimized[J]. IEEE Journal on Selected Areas in Communications, 2001, 19(9): 1744-1752. doi: 10.1109/ 49.947038.

STOJANOVIC M and PREISIG J. Underwater acoustic communication channels: propagation models and statistical characterization[J]. IEEE Communications Magazine, 2009, 47(1): 84-89. doi: 10.1109/MCOM.2009.4752682.

SINGER A C, NELSON J K, and KOZAT S S. Signal processing for underwater acoustic communications[J]. IEEE Communications Magazine, 2009, 47(1): 90-96. doi: 10.1109/ MCOM.2009.4752683.

许浩, 朱敏, 武岩波. 一种水声通信中的多阵元Turbo均衡算法[J]. 电子与信息学报, 2014, 36(6): 1465-1471. doi: 10.3724/SP.J.1146. 2013.01027.

XU Hao, ZHU Min, and WU Yanbo. An algorithm of multi-array Turbo equalization of underwater acoustic communication[J]. Journal of Electronics Information Technology, 2014, 36(6): 1465-1471. doi: 10.3724/SP.J.1146. 2013.01027.

LOU H A and XIAO C S. Soft-decision feedback Turbo equalization for multilevel modulations[J]. IEEE Transactions on Signal Processing, 2011, 59(1): 186-195. doi: 10.1109/TSP.2010.2083656.

VOGELBRUCH F and HAAR S. Low complexity Turbo equalization based on soft feedback interference cancelation [J]. IEEE Communications Letters, 2005, 9(6): 586-588. doi: 10.1109/LCOMM.2005.07016.

窦高奇, 高俊, 陶伟, 等. 基于序列检测的块判决辅助Turbo均衡器[J]. 电子与信息学报, 2009, 31(9): 2152-2156.

DOU Gaoqi, GAO Jun, TAO Wei, et al. Sequence-based block decision-aided equalizer for Turbo equalization[J]. Journal of Electronics Information Technology, 2009, 31(9): 2152-2156.

KIM K, KALANTAROVA N, KOZAT S S, et al. Linear MMSE-optimal Turbo equalization using context trees[J]. IEEE Transactions on Signal Processing, 2013, 61(12): 3041-3055. doi: 10.1109/TSP.2013.2256899.

杨晓霞, 王海斌, 汪俊, 等. 水声通信中基于信道辨识的盲Turbo均衡方法[J]. 应用声学, 2015, 34(2): 125-134.

YANG Xiaoxia, WANG Haibin, WANG Jun, et al. Blind Turbo equalization based on channel identification for underwater acoustic communications[J]. Journal of Applied Acoustics, 2015, 34(2): 125-134.

张冬玲, 杨勇, 李静, 等. 基于Turbo均衡和信道估计的单通道盲信号恢复算法[J]. 通信学报, 2014, 35(1): 47-61.

ZHANG Dongling, YANG Yong, LI Jing, et al. Blind data recovery of single-channel mixed signals based on Turbo equalization and channel estimation[J]. Journal of Chinese Institute of Communications, 2014, 35(1): 47-61.

PROAKIS J G and MANOLAKIS D G. Digital Signal Processing: Principles, Algorithms and Applications[M]. 4th ed, New Jersey: Prentice-Hall, 2007.

PROAKIS J G and SALEHI M. Digital Communications[M]. 5th ed, New York: McGraw-Hill, 2008: 640-672.

LEE S J, SINGER A C, and SHANBHAG N R. Linear Turbo equalization analysis via BER transfer and EXIT charts[J]. IEEE Transactions on Signal Processing, 2005, 53(8): 2883-2897. doi: 10.1109/TSP.2005.850375.

MOVAHEDIAN A and MCGUIRE M. On the capacity of iteratively estimated channels using LMMSE estimators[J]. IEEE Transactions on Vehicular Technology, 2015, 64(1): 97-107. doi: 10.1109/TVT.2014.2320928.

钟凯, 彭华, 葛临东. 基于Rimoldi分解的连续相位调制信号Turbo频域均衡算法[J]. 电子与信息学报, 2014, 36(5): 1190-1195. doi: 10.3724/SP.J.1146.2013.00990.

ZHONG Kai, PENG Hua, and GE Lindong. Turbo frequency domain equalization algorithm based on Rimoldi decomposition for continuous phase modulation signals[J]. Journal of Electronics Information Technology, 2014, 36(5): 1190-1195. doi: 10.3724/SP.J.1146.2013.00990.

施引文献

资源附件(0)

访问统计