本文针对矩形面阵的情况,讨论了面阵上不同阵元失效情况对阵列方向图、杂波特性及STAP性能的影响.可以发现,在加权的情况下失效阵元距阵面中心越接近,阵列方向图主瓣下降,副瓣升高越严重,子阵中失效阵元增多时,杂波自由度会随之增加,但当整个子阵失效时,杂波自由度反而会降低到接近原先无阵元失效的情况.文末讨论了阵元失效对目标信号相参积累的影响,对两种STAP算法在不同阵元失效情况下的性能进行了仿真分析,可以看出,阵元失效除了可能导致杂波自由度增加,还可能致使空域自适应方向图畸变,从而对自由度较匮乏的算法影响较大,最后针对空域自适应方向图畸变提出了一种空域深加权的改善方法,有一定的改善效果.
Effects of element failure in different cases are discussed on array pattern,clutter characteristic and space-time adaptive processing(STAP) performance in allusion to a rectangle array.When the array is weighted,the nearer the failing element is from the array center,the more the main lobe of array pattern descends and the side lobes ascend.Clutter rank increases as the number of the failing elements in sub-array increases,whereas when the sub-array fails,the clutter rank decreases to almost that of no element failure. In the end effects of element failure on signal coherent integration are analyzed, and two STAP algorithms are employed in computer simulation to illuminate the effects of element failure on STAP. Element failure can lead to space adaptive pattern aberrance besides increasing clutter rank, which affects the performance of algorithms with low degree of freedom (DOF) more. To solve the problem,an improved method of deeply-weighting is presented,and an improved performance is obtained.