摘要
研究了宽带信号波达角的精确估计方法,提出了一种适合宽带信号的干涉法测向算法。该算法利用阵元间的延时估计波达角。先对信号作快速傅里叶变换(fast Fourier transform,FFT),选取信号在6 dB带宽内的谱线,每根谱线看作一个单频信号,采用窄带鉴相方法对各单频信号分别鉴相并估计该频率点上的延时,最后对各延时估计值进行加权平均。证明了信号在各频率点上的能量与频率平方的乘积是最佳加权系数。本算法具有计算量小、算法简单等优点。延时估计的仿真性能接近克拉美-罗限。
A method of wideband signal＇s direction of arrival （DOA） estimation is addressed, and an algorithm of direction-finding applicable for wideband signals is presented. The time-delay between two elements is estimated and the DOA is obtained afterwards. Firstly, the wideband signal is decomposed into multiple singletone signals through fast Fourier transform（FFT）. The spectrums of FFT within 6 dB bandwidth are used to estimate the phase delay respectively, and then the time-delays are attained. Finally, the accurate time-delay estimate is given by weighting these estimates. The optimum weighting coefficients are given. The algorithm has low computation load. The computer simulation results of time-delay estimate show that the performance is approximately to the Cramer-Rao lower hound.
出处
《系统工程与电子技术》
EI
CSCD
北大核心
2009年第3期523-526,共4页
Systems Engineering and Electronics
关键词
宽带信号
子频带分解
渡达角估计
加权平均
wideband signal
sub-bands decomposition
DOA estimation
weighted average
