和差天线空时自适应测角方法及性能分析

Angle Estimation Approach and Performance Analysis for STAP with Sum-Difference Antenna

雷达模拟和差天线技术通过射频功率合成器形成和差波束,在目标角度测量中应用广泛,然而运动平台雷达经过空时自适应处理(Space-Time Adaptive Processing,STAP)后难以还原鉴角曲线,即自适应处理后的等效鉴角曲线与静态鉴角曲线发生偏离.针对此问题,本文提出和差天线体制雷达空时自适应测角方法 .该方法通过和差STAP算法抑制杂波后实现角度估计,并且通过理论推导建立了角度估计与和通道输出信噪比、差通道剩余杂噪比之间的关系,重点分析了杂波剩余对角度估计的非一致性影响.仿真实验验证了本文方法的有效性.

Analog sum-difference antenna radar forms sum-difference beam through radio frequency power synthesizer, which is widely used in target angle estimation. However, after space-time adaptive processing(STAP), it is difficult for moving platform radar to restore the angle identification curve, that is, the equivalent angle identification curve after adaptive processing deviates from the static angle identification curve. To solve this problem, this paper proposes a spacetime adaptive angle estimation method for STAP with sum-difference antenna system. In this method, the angle estimation is realized after suppressing clutter by sum-difference STAP algorithm. The relationship between angle estimation and the output signal-to-noise ratio of the sum channel, residual clutter-to-noise ratio of the difference channel is established by theoretical deduction. This paper analyzes the influence of clutter residue on the inconsistency of angle estimation emphatically. Simulation results verify the effectiveness of the proposed method.