互质阵列空洞中内插阵元的DOA估计算法

DOA estimation algorithm with interpolated array elements for coprime array holes

针对互质阵列差联合构造的虚拟阵元中空洞不可用而导致阵列最大可用自由度减少的问题,提出了一种新的互质阵列中添加天线的方法。该方法中内插最少的天线数使虚拟阵列达到最大可利用自由度,且内插天线数并不改变互质阵列的原始孔径大小,在相同信噪比情况下,实现更为精准的波达方向(DOA)估计。先找出虚拟阵元中空洞所处位置的规律,根据其规律,针对部分虚拟阵元空洞位置,在与之对应的互质阵列位置内插阵元天线,使得虚拟阵元中空洞均被填充,最终获取最大自由度的虚拟均匀连续阵元。采用ESPRIT算法,仿真结果表明:算法在DOA估计数、估计分辨率以及估计精度都得到了明显的改善。

In order to solve the reduction of maximum freedom degree,which was result by the holes-existing in the virtual arrays constructed with co-prime arrays differential combination were unavailability,a new method for adding antennas in the co-prime arrays was proposed.In this method,interpolated minimum antennas number and freedom maximization in the virtual arrays,and the number of interpolated antennas did not change the original aperture size of the co-prime arrays.In same SNR,the direction of arrival(DOA) estimation was more accurate.The scheme first found the regular pattern of the holes position in virtual array elements,according to the regular pattern,for some holes-existing in the virtual arrays and interpolated array element antenna in the corresponding position of the coprime arrays,until the holes-existing in the virtual arrays were filled.Therefore,maximum freedom degree in virtual uniform and uninterrupted array element was gained.The ESPRIT algorithm was used in this paper,and the simulation results showed that the algorithm had improved the DOA estimation,estimation resolution and estimation accuracy.