一种稳健的未知信源数目的DOA估计算法

现有的DOA估计算法都是基于较为理想的模型提出的,在实际工程中,这些算法的性能受快拍数少、阵列误差的影响会严重恶化.针对这一问题,文中提出一种稳健的未知信源数目的 DOA估计算法.该算法先利用投影变换技术对阵列接收数据进行预处理,抑制模型误差并降低数据维数,从而提高算法的稳健性并减少计算量,然后根据变换后的m-Capon算法空间谱函数估计DOA.仿真结果表明:该方法在快拍数少、系统误差不大(小于10%)的情况下依然具有一定的方位"超分辨"能力,而且有较强的稳健性,性能远优于现有的MUSIC算法和对角加载m-Capon算法.

A Robust DOA Estimation Algorithm Under the Condition of Unknown Number of Signal Sources

As the existing DOA(Direction of Arrival) estimation methods are all based on ideal circumstances,their performance may highly degrade when they are applied to practical situations with small snapshot number and certain array error.In order to solve this problem,this paper proposes a robust DOA estimation algorithm under the condition of unknown signal source number.In this algorithm,the data received by the array are pretreated via the projection transformation to inhibit model errors and reduce data dimension,thus improving the robustness and lightening the computation load.Then,the DOA is estimated according to the transformed m-Capon spatial spectrum function.Simulated results indicate that the proposed algorithm outperforms the MUSIC algorithm and the dia-gonal loading m-Capon algorithm because it is of certain super-resolution ability and strong robustness even in the direction finding with short snapshot and small system error(being less than 10%).