拖线阵机动时的自适应波束形成

提出了一种MVDR(最小方差无失真响应)的改进算法,用以解决常规MVDR算法由于阵形时变而出现的性能下降问题。在获得时变阵形估计数据的基础上,该算法以统计时段内的平均阵形为基准阵形,在每个扫描方向上根据实际阵形和基准阵形的差异对阵列互谱矩阵多样本进行相位补偿,从而实现统计时段内的互谱矩阵多样本相干累加和目标检测。数值仿真与海上实验数据处理结果表明:与传统MVDR算法相比,改进算法有效缓解了时变阵形下的目标测向角度模糊问题,可提高拖线阵目标左右舷分辨性能、增强弱目标检测能力。 

Adaptive beamforming of a time-varying towed array

During maneuvering,performance of the Minimum variance distortionless response(MVDR) beamforming will greatly degrade due to the shape error of a towed array.Under the assumption that the shape of a towed array changes in a known way during the observation interval,an improved MVDR method is proposed.A static array with average shape during the observation interval is taken as a reference array shape.The phase difference of cross spectral density matrix(CSDM) between the time-varying array and the reference one is compensated on each azimuth.The CSDM accumulation can be achieved in the end.The simulation and experimental results show that the improved method has better performance than conventional MVDR with time-varying array,especially in solving the left-right target ambiguity and detecting weak signals.