基于正定优化的分布式阵列舰载米波雷达的高分辨角度估计

High resolution DOA estimation based on SDP for distributed subarray antenna shipborne VHF radar

针对米波雷达波长较长及在舰载平台上安装大孔径均匀阵列天线工程上难以实现且不利于自身的隐身的问题,提出了分布式阵列天线结构和基于正定优化的分布式阵列天线米波雷达高分辨角度估计算法。该算法从分布式阵列天线的空域相关阵出发,利用矩阵完型理论,由矩阵直接增广法得到同孔径均匀阵列的增广相关阵,再利用正定优化算法将增广相关阵修正为正定厄密的Toeplitz相关阵,实现了分布式阵列的流形解模糊及信号相参处理,从而达到了分布式阵列的孔径扩展。仿真结果验证了分布式阵列及基于SDP的修正算法的正确性与有效性,也验证了经过SDP修正后分布式阵列的高分辨性能。

Due to the longer wavelength of VHF radar and limited surface available on many shipborne platforms,the large uniform antenna array is practically prohibited and is not conducive to own stealthy performance,a novel distributed subarray antenna（ DSA） is proposed. For distributed subarray antenna VHF radar,an high resolution direction of arrival estimation algorithm based on Semidefinite Programming（ SDP） is also proposed. The algorithm from spatial autocorrelation matrix of the DSA is rooted matrix completion,which firstly attains an augmented matrix of the same aperture uniform array antenna as DSA through direct augmented approach（ DDA）. Then the augmented matrix is revised to a positive definite Hermitian Toeplitz autocorrelation matrix. So the ambiguity of the DSA manifold is resolved,and coherent signal processing and aperture extension of DSA are accomplished. Simulation results demonstrate the validity and effectiveness of the revised algorithm based on SDP,also demonstrate the high resolution performance of DSA.