虚拟极化在雷达目标检测的得益研究

Investigation of Virtual Polarization Gain from Radar Targets Detection

为了定量研究虚拟极化在雷达目标检测的得益,在实测数据基础上分别基于参数估计法和搜索法计算极化状态,提出虚拟极化得益有别于极化分集的得益,给出了虚拟极化得益的评估方法。实验结果表明虚拟极化的得益最大为3 dB,虚拟极化的得益与接收双通道SNR的差值的大小成反比例关系:接收双通道的SNR差值为0 dB～6 dB时,虚拟极化得益为1 dB～3 dB;接收双通道SNR差值>6 dB时,虚拟极化得益<1 dB,此时虚拟极化合成没有意义。此外,从时间成本和效果上评估,优选参数估计法计算极化状态。从应用角度上分析,虚拟极化在小SNR目标检测具有潜力,而对于大SNR的目标检测可以增加探测距离。

In order to quantitative investigation of virtual polarization gain（VPG） of radar targets detection,parameter estimation method and searching method are applied for calculating polarization state on the basis of actual data,VPG is different from the gain of polarization diversity,appraising method of VPG is proposed.Experiment results show that the maximum VPG is 3 dB,VPG is inversely-proportional to SNR difference of double receiving systems（DDRS）： while SNR of DDRS is 0 dB^6 dB,VPG is 1 dB^3 dB;while SNR of DDRS6 dB,VPG1 dB,it is useless.Besides,parameter estimation method is preferred to calculate polarization state in time cost and effect evaluation.In application,virtual polarization has potentiality in small SNR radar targets detection and increase the detection range for large SNR radar targets detection.