带有误差反馈结构的多天线变步长均衡算法

doi:10.3969/j.issn.1001-2400.2017.05.027

摘要/Abstract

摘要：

在多天线分集自适应判决反馈均衡器中，有限长均衡器输出的误差信号不具有尖锐的自相关特性，从而导致稳态误差的提高受到了一定的影响，针对该问题，在多天线分集自适应判决反馈均衡器中引入误差反馈结构，在最小均方准则下，通过消除误差信号的相关性来提高分集均衡输出信号的质量．但是，引入误差反馈结构降低了算法的收敛速度，通过重构步长与误差信号的非线性关系，对变步长技术采用的sigmoid函数进行修改，使算法在初始阶段步长较大．该算法适用判决反馈结构，并且明显提高了收敛速度．仿真结果表明，所提算法能够在只增加少量计算复杂度的情况下，同时实现收敛速度和均方误差性能的提升．

关键词: 空间分集, 判决反馈均衡, 误差反馈, 码间串扰, 变步长

Abstract:

Owning to the correlation of the error signal in multi-antenna diversity adaptive decision feedback equalization being not same with white noises', the equalization performance is constrained. This paper adds error feedback filters to the traditional multi-antenna diversity adaptive decision feedback equalizer. The proposed structure can decrease the correlation of the error signal to increase the performance under the mean square error criterion. However, the proposed structure lowers the algorithm's convergence speed. Consequently, a nonlinear function between step size and error signal by modifying the sigmoid function in order to make this variable step-size measure be adapted to decision feedback equalizers is proposed. The modified algorithm has a larger step size at beginning. Simulation results show that the proposed approach can increase the speed and lower mean square with only little increase in computation.

Key words: spatial diversity, decision feedback equalization, error feedback, Inter-symbol interference, variable step size

侯箫剑;许华;曾乐雅. 带有误差反馈结构的多天线变步长均衡算法[J]. 西安电子科技大学学报, 2017, 44(5): 158-164.

HOU Xiaojian;XU Hua;ZENG Leya. Variable step size multi-antenna diversity equalization algorithm using error feedback[J]. Journal of Xidian University, 2017, 44(5): 158-164.

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