基于最大似然的同频混合信号联合定时估计算法  

ML-based joint timing estimation algorithm for co-frequency signals

作　　者：廖灿辉[1,2] 周世东[1] 朱中梁[2] 

机构地区：[1]清华大学微波与数字通信国家重点实验室,北京100084 [2]信号盲处理国防科技重点实验室,四川成都610041

出　　处：《系统工程与电子技术》2010年第6期1121-1124,共4页Systems Engineering and Electronics

基　　金："十一五"总装预研基金;国防科技重点实验室基金资助课题

摘　　要：针对同频干扰下的混合信号时延估计问题进行研究,提出了一种基于最大似然准则的联合定时估计算法。该算法在推导似然函数的基础上,采用分级搜索方法估计信号时延,能同时实现干扰信号与有用信号的联合定时。相比传统的单信号时延估计,该算法需要有更长的观测数据长度;算法对频偏误差不敏感,在归一化频偏(相对于符号速率)小于2%时性能损失很小。仿真结果验证了算法的有效性。A maximum-likelihood（ML） based algorithm for joint timing estimation of both useful signal and co-channel interference is proposed.The likelihood function is first derived,and then the timings of two signals are identified in the two-dimensional timing space by using a scale searching method.Compared with the traditional algorithm for single-signal timing estimation,the proposed algorithm requires more observation data.The algorithm is little sensitive to frequency offsets and shows small performance attenuations for a frequency shift of 2% of the symbol rate.The simulation results verify the effectiveness of the proposed algorithm.

关 键 词：定时估计 同频干扰 最大似然 分级搜索 

分 类 号：TN911.7[电子电信—通信与信息系统]