基于LDPC码的联合半盲均衡与解码研究

摘要

在数字无线通信中,由于多径效应将导致信号在接收端产生严重的符号间干扰(inter-symbol interference,ISI),为克服ISI,在接收端一般通过均衡器来校正或补偿系统特性.传统的均衡器需使用大量的导频符号才能获得较好的均衡性能,提出的基于线性规划(linear programming,LP)的联合半盲均衡与译码算法,以较少的导频数目获得了较优异的性能,分析了该算法的不足,并提出一种优化算法.仿真结果表明,使用同样的导频数,该优化算法明显降低均衡器的复杂度,同时改善了系统性能.%In digital wireless communication system, signals at the receiver suffer serious inter-symbol interference ( ISI) caused by the multi-path effect. In order to overcome the ISI problem, an equalizer is implemented to correct or compensate the system. To get a better performance, traditional equalizers often require a substantial number of pilots. Recently the re-searchers investigate the joint semi-blind equalization and decoding algorithm, which improves the performance significantly with fewer pilot symbols. In this paper, we analyze the shortcomings of the current method and propose an optimization e-qualization algorithm. Simulation results show that this optimization approach exploits the same number of pilots to obtain a vast reduction of equalization complexity and improves the equalization performance significantly.