收稿日期: 2016-05-12
修回日期: 2016-11-14
网络出版日期: 2017-03-30
基金资助
安徽省自然科学基金（No.1308085QF99）资助
Blind Equalization with Adaptive Variable Step Sizes Based on Parallel Laguerre Filter
Received date: 2016-05-12
Revised date: 2016-11-14
Online published: 2017-03-30
深衰落信道会引起抽头系数长和误码率高等问题.在分析现有滤波器结构及盲均衡算法的基础上，提出了自适应变步长并行Laguerre盲均衡算法.该算法采用Laguerre序列代替传统抽头延迟，缩短了抽头系数，并借助判决引导算法和分数间隔思想，加快了算法收敛速度.鉴于步长因子对盲均衡器收敛速度、剩余码间干扰影响较大，对不同自适应步长算法进行了分析和比较.在此基础上提出了适用于高速通用数据链信号盲均衡的步长修正方案.实验表明该算法较传统算法在收敛速度、误码性能方面均有所提升.
关键词： 盲均衡; Laguerre滤波器; 通用数据链; 变步长
崔琳, 杨俊安, 王伟, 刘辉 . 自适应变步长并行Laguerre盲均衡算法研究[J]. 应用科学学报, 2017 , 35(2) : 207 -216 . DOI: 10.3969/j.issn.0255-8297.2017.02.007
A blind equalization algorithm with adaptive variable step sizes based on parallel Laguerre filter is proposed to overcome problems such as long tap coefficients, and high bit error rate (BER) caused by deep fading channels. By analyzing existing filter structures and blind equalization algorithms, the proposed algorithm replaces traditional tapped delay with Laguerre sequence to make tap coefficients shorter. Meanwhile, convergence is accelerated by using a decision-directed algorithm and a fractionally spaced structure. Since the step size has a great effect on convergence speed and residual error, different algorithms with variable step sizes are compared. Based on the comparison, a revised equalization algorithm structure is devised to achieve the most suitable step sizes for high-speed common data link (CDL). Compared with traditional blind equalization algorithms, experimental results show that the proposed method improves equalization performance and reduces BERs remarkably.
Key words： blind equalization; variable step size; common data link; Laguerre filter
[1] Keller J. Air force eyes network-centric warfare common data link of the future[J]. Military and Aerospace Electronics, 2013, 24(3):6-8.
[2] Bianchi P, Loubaton P. On the blind equalization of continuous phase modulated signals using the constant modulus criterion[J]. IEEE Transactions on Signal Processing, 2007, 55(3):1047-1061.
[3] Shi Q H. Blind equalization and characteristic function based robust modulation recognition[C]//14th International Conference on Advanced Communication Technology, 2012:660-664.
[4] Benevenuto N, Ciccotosto S, Tomasin S. Iterative block fractionally spaced nonlinear equalization for wideband channels[J]. IEEE Wireless Communication Letters, 2015, 4(5):489-492.
[5] Zeolla D, Antonino A, Bosco G. DFE versus MLSE electronic equalization for gigabit/s SI-POF transmission systems[J]. IEEE Photonics Technology Letters, 2011, 23(8):510-512.
[6] Cheng H Y, Chu C Y, Cheng Y L. Robust decision feedback equalizer scheme by using sphere-decoding detector[C]//IEEE International Conference on Acoustic, Speech and Signal Processing, 2014:5074-5077.
[7] Benjangkaprasert C, Sirithummachak P. Adaptive equalizer for DS-CDMA multi-user communication system based on Laguerre filter structure with sign-algorithm[C]//Information Science, Electronics and Electrical Engineering, 2014:1100-1103.
[8] Ebrahimi R, Seydnejad S R. Wideband Laguerre adaptive array with pre-steering constraints[J]. IET Signal Processing, 2015, 9(7):529-536.
[9] Haykin S. Adaptive filter theory[M]. 5th ed. Englewood Cliffs:Prentice-Hall, 2013.
[10] Ng W C, Nguyen A T, Ayotte S. Impact of sinusoidal tones on parallel decision-directed phase recovery for 64-QAM[J]. IEEE Photonics Technology Letters, 2014, 26(5):486-489.
[11] Rotaru M, Albu F, Coanda H. A variable step size modified decorrelated NLMS algorithm for adaptive feedback cancellation in hearing aids[C]//International Symposium on Electronics and Telecommunications. IEEE, 2012, 13(1):263-266.
[12] 郭业才,纪娟娟. 基于正交小波包变换的变步长双模式盲均衡算法[J]. 系统仿真学报,2011, 23(2):335-338. Guo Y C, Ji J J. Variable step-size dual-mode blind equalization algorithm based on orthogonal wavelet packet transform[J]. Journal of System Simulation, 2011, 23(2):335-338. (in Chinese)
[13] Hamidia M, Amrouche A. Improved variable step-size NLMS adaptive filtering algorithm for acoustic echo cancellation[J]. Digital Signal Processing, 2015, 49(C):44-55.
[14] Gao Y, Qiu X Y. A new variable step size CMA blind equalization algorithm[C]//Control and Decision Conference, 2012, 23(1):315-317.
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