基于实测和差波束天线方向图的ΣΔSTAP性能分析

Performance Analysis of ΣΔSTAP Based on Measured ΣΔ-Beam Antenna Pattern

基于实测和差波束天线方向图研究ΣΔSTAP的性能,文中详细推导了和差波束天线方向图的空时二维杂波协方差矩阵和ΣΔSTAP算法的最佳权矢量。理论分析和仿真计算结果表明,和差波束低副瓣增益有效抑制了旁瓣杂波,降低了杂波自由度。当杂波起伏或载机速度提高时,杂波自由度增加,ΣΔSTAP算法的系统改善因子凹口相应展宽,慢动目标检测性能下降。ΣΔSTAP算法能迅速应用于机载火控雷达,有效提高慢动目标检测性能。

The performance of ∑△STAP based on the measured ∑△-beam antenna pattern is analyzed. The clutter covariance matrix and the optimum weight vector for ∑△STAP under various situations are derived based on the measured ∑△-beam antenna pattern. Theoretical analysis and calculational results are presented to demonstrate that due to the low sidelobe gain of ∑△-beam, the degree-of-freedom （DOF） of the clutter is significantly decreased. Clutter fluctuation or increased platform speed can increase the clutter DOF, thus leading to the clutter spectrum widening and degrading the detecting performance of slow moving targets. This approach can be efficiently applied into airborne fire control radar and the moving target detection performance is improved.