均匀圆形阵列基于指数形式导数更新的STAP算法

Exponent-Derivative-Based Updating STAP Method for Uniform Circular Array

机载相控阵雷达采用均匀圆形阵列天线具有全方位扫描、同时实现仰俯-方位角估计和天线方向图好等优点;但圆形天线特殊的几何结构使得其各距离单元回波不是独立同分布的样本,造成了空时自适应处理技术性能急剧下降。本文提出了一种基于指数形式导数更新(Exponent derivative based updating,EDBU)的杂波抑制方法,该方法通过对样本数据进行指数形式扩展,减小均匀圆形天线机载雷达杂波的非均匀程度,提高统计型空时自适应处理(Space time adaptive processing,STAP)处理器的性能。仿真结果表明,该方法不仅明显好于局域处理和杂波距离依赖性补偿算法,而且也优于传统的基于导数更新法。

Airborne radar with uniform circular array （UCA） antennas has the merits of all-orientation space scanning, joint elevation-azimuth estimation, and good beamform when the beam center deviates from the normal of the array. But the clutter distribution of UCA varied with ranges and received data in different range cells are not independently identically distributed （IID） samples for its geometry special- ty, which results in the significant degradation in traditional space time adaptive processing （STAP） method. A new STAP method, namely exponent derivative based updating algorithm, is proposed. In the method, the change of adaptive weight is supposed as an exponential function and the range-depend- ency of UCA can be effectively reduced by extending the received data vectors. Simulation results verify that the proposed method outperforms significantly both localized processing and range-dependency com- pensation methods, as well as the traditional derivative-based updating algorithm.