Abstract:

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 diagonal 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%).

Key words: DOA estimation, array signal processing, direction of arrival, m-Capon method, array error, snapshot number