一种同频重叠信号自适应盲分离算法  

Algorithm of blind separation of frequency over lapping signals

作　　者：李天赐[1] 臧广达 卢筑飞 潘国良[3] 支琤[1] 

机构地区：[1]上海交通大学上海市数字媒体处理与传输重点实验室,上海200240 [2]中国船舶重工集团第七一O研究所,湖北宜昌443000 [3]中国国际航空股份有限公司规划发展部,北京101312

出　　处：《信息技术》2014年第10期1-5,10,共6页Information Technology

基　　金：国家自然科学基金(61102051;61221001;61301117);863计划(2012AA011701;2012AA121601);上海交通大学科技创新基金(AF0300021);上海市数字媒体处理与传输重点实验室(12DZ2272600)

摘　　要：针对同频重叠信号的单通道盲分离问题,提出了一种自校正频偏和调整幸存路径数目的盲分离算法。针对两路QPSK信号同频重叠的且存在频率漂移等单通道信号盲分离,推导了基于过采样的信道参数估计模型,利用纠错编码的方法降低误码率,利用指数加权递归最小二乘法(RLS)估计信道参数,并利用估计出的信道参数校正频率漂移等带来的频率偏差,通过在逐幸存路径(PSP)算法调整幸存路径数目解决信道参数收敛和计算复杂度之间的矛盾,提高了频率漂移等变化信道下的参数估计性能,并降低了计算量。仿真结果表明,该算法能够较好地实现频偏自校正,弥补频率漂移带来的影响,同时可以大幅度降低计算量。This paper presents a blind separation algorithm of frequency tuning and survivor path adjustment in single channel of co-frequency overlapping signals. Considering the mixture of two QPSK signals in the single channel with frequency shift, it derives a formula of parameter-estimation under oversampling, using error correction coding aided to reduce bit error rate （BER）, utilizing the exponentially weighted recursive least squares （RLS）to estimate the channel parameters, using estimated the channel parameters to adjust frequency offset caused by frequency shift. It also solves the contradictions of channel parameters between convergence and computation by adjusting the survivor-path number in per-survivor processing（PSP） algorithm. And the algorithm brings the benefits of improving the performance of channel parameters estimated in dynamic channel with frequency shift and the reduction of computation. The simulations show that this algorithm is able of frequency tuning to improve the performance in frequency shift and decrease the total computation greatly.

关 键 词：频偏自校正 递归最小二乘法 幸存路径调整 单通道盲分离 

分 类 号：TN911[电子电信—通信与信息系统]