关键词: 目标检测, 方位估计, 角度分辨率, 合成孔径, 最小方差无失真响应（MVDR）

Abstract: In the field of array signal processing, the detection of the number of signals and estimation of the Direction of Arrival（DOA） of signals are two important issues. They are generally solved separately with some algorithms dedicated to detection and other algorithms dedicated to DOA estimation. An integrated method called Synthetic Aperture Technique based Detection and Estimation（SATDE） is proposed for multi-target detection and DOA estimation by underwater moving array. The proposed method exploits the synthetic aperture technique to achieve high angular resolution and the energy detection idea embodied in Minimum Variance Distortionless Response（MVDR）spectrum function to determinate the number and DOA of signals at the same time. Simulations and experimental results show that the proposed method yields better detection performance than conventional detection methods such Akaike Information Criterion（AIC） and Minimum Descriptive Length（MDL） for closely-spaced coherent signals and produces correct DOA estimations at the same time.

Key words: target detection, DOA estimation, angular resolution, synthetic aperture, Minimum Variance Distortionless Response（MVDR）