差分酉空时协作系统的多符号裁减自动球形译码

Multiple-symbol pruning automatic sphere detectors for differential unitary space-time cooperative systems

鉴于差分协作系统中多符号差分检测(multiple-symbol differential detection,MSDD)算法计算复杂度高的缺点,引入裁减自动球形译码(pruning automation sphere detection,PASD)算法来降低差分酉空时协作系统的检测复杂度.PASD算法是在球形译码的基础上,结合自动球形译码和裁减球形译码的思想而提出的.通过对扩展节点所消耗的复杂度和系统的误码率两方面来分析译码算法的性能.仿真分析表明,在差分酉空时协作系统中,PASD算法在误码性能几乎不变的情况下,复杂度曲线比球形译码(sphere detection,SD)算法收敛迅速.其中在分组长度N=5、信噪比SNR=15dB的情况下,PASD、SD算法的扩展点数分别为14.138 6、78.950 5,大大降低了系统的复杂度;同时,当SNR>16dB时,协作节点的增加有利于提高系统的误码性能,系统的复杂度性能并没有很大的损失.

In view of the deficiency of the high calculating complexity for the differential cooperative systems in multiple-symbol differential detection algorithms,introduces a pruning automatic sphere decoding(PASD) algorithm to reduce the complexity of differential unitary space-time cooperative systems.The PASD algorithm was proposed on the basis of the sphere detection that combines automatic sphere decoding(ASD) and pruning sphere decoding.The performance of the decoding algorithm through both the complexity of consumption visited nodes and BER was analysed.The simulation analysis shows that in the differential unitary space-time cooperative system,the BER performance of PASD algorithm is almost the same,while the complexity of the curve converges more quickly than SD algorithm.While in the case of observe window size N was 5 and the signal to noise ratio was 15 dB,the visited nodes of PASD and SD algorithm is 14.138 6,78.950 5,respectively.It greatly reduces the complexity of the system.At the same time,when the SNR>16 dB,with the increase of cooperative nodes,the BER performance of the system will be improved.However there is no great loss on the complexity performance of the system.