高速移动环境下低复杂度OTSM迭代rake均衡方法

Iterative rake equalization method for low-complexity OTSM in high-speed mobile environment

针对现有正交时序复用(OTSM)均衡方法抗噪性能不佳、计算复杂度高的问题,提出了一种基于最大比合并(MRC)的低复杂度迭代rake均衡器。其主要思想是利用MRC在时延-时域中迭代提取并相干合并发射符号的接收多径分量,以提高合并信号的信噪比。为加快MRC迭代算法收敛,设计了一种单抽头时频均衡器为其提供初始估计,随后结合外部纠错码进一步提高误码性能。仿真结果表明,基于MRC的迭代rake均衡器性能显著优于LMMSE线性均衡器,与目前广泛使用的高斯-赛德(GS)迭代均衡器相比,性能和计算复杂度都有较大提升。

Aiming at the problems of poor anti-noise performance and high computational complexity of the existing orthogonal time sequency multiplexing(OTSM)equalization methods,a low-complexity iterative rake equalizer based on maximum ratio combining(MRC)was proposed.The main idea was to use MRC to iteratively extract and coherently combine the received multipath components of the transmitted symbols in the delay-time domain to improve the signal-to-noise ratio of the combined signal.In order to speed up the convergence of the MRC iterative algorithm,a single-tap time-frequency equalizer was designed to provide an initial estimate,and then combined with an external error correction code to further improve the bit error performance.The simulation results show that the performance of the iterative rake equalizer based on MRC is significantly better than that of the LMMSE linear equalizer,and the performance and computational complexity are greatly improved compared with the currently widely used Gauss-Seidel(GS)iterative equalizer.