基于四阶累积量的非圆信号测向方法

A New Forth-Order Direction Finding Algorithm for Noncircular Signals

对通信系统中大量使用的BPSK等非圆信号测向,可以采用共轭扩展MUSIC(CE-MUSIC)算法,也可以采用基于四阶累积量的MUSIC-like算法。CE-MUSIC算法没有利用高阶信息,MUSIC-like算法没有利用信号的非圆信息,性能均受限。该文提出的四阶扩展MUSIC(FO-EMUSIC)算法利用了非圆信号在四阶累积量中的信息,分辨力和测角精度明显优于MUSIC-like算法,略优于CE-MUSIC算法,可测向阵元数大于CE-MUSIC算法和MUSIC-like算法。针对均布线阵。为减小计算量,还提出了FO-EMUSIC/ULA算法。仿真实验验证了FO-EMUSIC算法的优良性能。

Conjugate Extended MUSIC （CE-MUSIC） and MUSIC-like algorithm can be used to estimate the directions of arrival of noncircular signals （e,g, BPSK modulated signals） which are widely used in communication systems. The performance of these two algorithms is not so good because no high order information is used in CE-MUSIC algorithm and no noncircular information is used in MUSIC-like algorithm which is based on forth-order cumulants. In this paper, a new direction finding algorithm called Forth-Order Extended MUSIC （FO-EMUSIC） for noncircular signals is proposed. It can detect more noncircular signals than MUSIC-like and CE-MUSIC algorithms and has better performance （in terms of resolution and angular precision） than MUSIC-like algorithm, and a little better than CE-MUSIC）algorithm. A new FO-EMUSIC algorithm for Uniform Linear Array （ULA） called FO-EMUSIC/ULA which needs much less computation load than FO-EMUSIC is also proposed in this paper. Simulation results show the better performance of FO-EMUSIC than MUSIC-like and CE-MUSIC algorithms.