一种新的快速零陷形成技术

A New Technology for Fast Nulling

分解大型阵列为关于阵列中心对称的两个子阵,对内子阵进行阵元位置微扰形成指定零陷。借助对微扰后方向图的泰勒展开进行线性化,以微扰后方向图形变最小化为目标,将指定方向控零的约束条件分实部、虚部分别约束微扰值,运用方向导数法快速求解出微扰值,实现了在指定方位快速控零,并提出引入小值控制零陷深度。方法不改变阵列孔径,在指定方向控零后能维持原主波束形状、副瓣水平不变,仿真表明本方法的有效性和优越性。

The technique is based on dividing a large array into two contiguous sub-arrays symmetrical to the array center. The element positions perturbation of the inner array is used to form the nulls in the antenna pattern. The technique linearizes the antenna pattern by using the Taylor expansion, then minimizes the change of the antenna pattern after perturbation, accompanies perturbation vector conformant to both of constraint term＇s real part and imaginary part, computes perturbation vector by means of directional differential coefficient, realizes the fast null steering in required angle area, and introduces small math value to control the null. The method changes the primary pattern to the least extent, with no change of array size. The simulation results verify its validity and advantages.