基于稀疏表示的宽带DOA估计

Wideband DOA estimation based on sparse representation

提出一种基于空频域稀疏表示的宽带DOA估计方法。首先,用空间频率代替频率和方位角的二维组合构建过完备字典,字典的长度仅相当于窄带信号DOA估计的字典长度,却能实现宽带DOA估计。然后,对频域协方差矩阵进行特征分解,利用主特征向量建立稀疏模型进行DOA估计,提高了算法在低信噪比下的性能。理论分析和实验,证明了该方法可以对宽带范围内的多个窄带和宽带信号进行高精度的DOA估计,同时不需要进行任何处理即可直接应用于相干信号。

A novel wide-band DOA（direction of arrival） estimation method based on space-frequency sparse repre-sentation is proposed.Firstly,the over-complete dictionary is constructed by using space-frequency to replace the 2D combination of frequency and azimuth.Although the length of constructed dictionary equates to the length of narrow sig-nal DOA estimation＇s dictionary,it could cover the whole wideband.Then the large eigenvectors of frequency covariance matrix were used to construct the sparse DOA estimation model to improve the performance in the low SNR（signal to noise ratio）.The theory analysis and experiment results indicate that the proposed method is correct and effective to esti-mate the frequency and DOA of multi narrow signals and wideband signals with wide-band receiver.And this method can adapt to coherent signals without further processing.