相控阵天线幅相控制仿真

相控阵天线的幅度方向性函数及方向图是其重要的特性参数，为了实现相控阵天线扫描方向图的仿真，利用方向性函数与离散傅里叶逆变换（IDFT）之间的相似性，建立以快速傅里叶逆变换（IFFT）为核心的扫描算法，实现了一维直线相控阵天线发射的扫描方向图幅相控制仿真，包括小角度精确移相、小角度均匀误差移相、小角度非均匀误差移相、大角度移相以及窗函数幅相控制移相等情况下的扫描方向图仿真，仿真结果表明：当精确移相时，方向图能够实现准确扫描；当移相有误差时，小角度非均匀误差移相的扫描角优于均匀误差移相的方向图；当大角度（68°左右）扫描时，方向图出现明显栅瓣；采用窗函数幅度加权获得了探测精度高的低旁瓣方向图。

Simulation of Amplitude Control and Phase Shifting of Phased Array Antennas

The amplitude directive function and its patterns are important characteristic parameters of phased array antenna （PAA）. In order to simulate scanning direetivity patterns of PAA, the similarity be tween amplitude directive function and inverse discrete Fourier transform （IDFT） is utilized to establish a set of scanning arithmetic in which inverse fast Fourier transform （IFFT） is the key. The simulations of scanning directivity patterns of onedimensional linear PAA are carried out by controlling amplitude and phase, which include accurate phase shift at small angles, linear error phase shift at small angles, random error phase shift at small angles, wide angle phase shift and window function amplitude control phase shift. The simulation results indicate that the scanning directivity patterns can he achieved by shifting phases ac curately ; that the scanning directivity patterns at small angles of shifting phases with random errors are bet ter than those of shifting phases with linear errors; that some obvious grating lobes appear in the scanning directivity patterns at wide scanning angles （around 68 °） ; and that the directivity patterns which have low side lobes so as to improve detection accuracy are obtained by weighted amplitudes with different window functions.