强相干干扰下基于二阶锥规划的圆弧阵宽带二维成像

摘要

To sol ve the problem that in two-dimensional imaging the target under water is easily hidden by the strong coherent interference, and high side lobe of arc array beam pattern causes more false alarm, an optimized two-dimensional imaging method based on second-order cone programming is proposed. Not only the strong coherent interference is suppressed, but also the side lobe is controlled well with the method. The issue that the sliding window in time domain leads to the difference between the steering vector and array manifold is analyzed, which causes the mismatch between the weights computed by the second-order cone programming and steering vector, and the failure to satisfy the side lobe control and null design requirement. To solve the issue, the method using the theoretical steering vector calculated by the sliding window in time domain instead of the array manifold to design the second-order cone programming weights is proposed, and the optimizations of the beam pattern and the arc array two-dimensional imaging are combined by the improved second-order cone programming weights .The validity of the proposed method is demonstrated by computer simulation and the pool experiment.%该文针对水下目标2维成像在强相干干扰情况下，目标亮点容易被淹没的问题，以及圆弧阵波束的高旁瓣给图像检测带来较多虚警的缺陷，提出基于二阶锥规划的宽带2维成像优化方法。该方法在对相干干扰抑制的同时，很好地控制了波束的旁瓣。分析了2维成像算法流程中由于时域滑窗导致阵列的接收信号矢量与阵列流形不同，造成二阶锥规划设计的权值与阵列的接收信号矢量失配，旁瓣控制和零陷设计无法满足设计的要求。针对该问题提出利用计算出的滑窗理论阵列的接收信号矢量代替阵列流形来进行二阶锥权值设计的方法，通过改进的二阶锥权值，将波束优化与圆弧阵的2维成像优化相结合。计算机仿真和水池实验都验证了该方法的有效性。