多项式聚焦矩阵到达角估计法的阵元间距限制

摘要

Arithmetic for direction of arrival (DOA) estimation of wide-band signal always needs beforehand estimation except the method based on polynomial focusing matrix.But the application condition and estimation performance hasn't been reported yet.Therefor,computer simulation of DOA estimation based on polynomial focusing matrix was put forward.The simulation result showed that,the method of polynomial focusing matrix had advantages of less calculation,good noise immunity.And it could also be applied to DOA estimation of coherent wide-band signals.Of this method,the array element distance had to be far less than the signal's half wave-length,or it would cause estimation error.Theoretical analysis showed that,the reason of error was approximation of polynomial focusing matrix.%宽带信号的到达角估计方法的角度信息一般需要对信号到达角进行预估计.多项式聚焦矩阵的方法不需要对到达角进行预估计,但是关于该方法的适用条件和估计性能尚未见报道.为此,对基于多项式聚焦矩阵的宽带信号到达角估计方法进行仿真.发现多项式聚焦矩阵具有计算量小、抗噪性好、能对相干信号进行到达角估计的优点,但需要满足阵元间距远小于信号半波长的条件.当阵元间距不满足该条件时,会引入较大的估计误差.理论分析表明,产生误差的原因是由于多项式聚焦矩阵进行了近似所引入的.