针对当前机载雷达面临强杂波抑制和微弱目标检测等难点问题,提出了一种极化空时联合处理新方法.该方法充分利用了目标与杂波在极化域、空域和时域(Doppler域)的特征差异,提高了抑制杂波、增强目标的能力.本文首先建立了机载极化阵列雷达接收信号模型和滤波算法模型.其次,利用分辨格思想及特征值、特征向量和功率谱的关系,构建了完全极化情况下杂波协方差矩阵新的等价关系.在此基础上,详细推导了新方法的杂波抑制性能,得到了输出信干噪比(SINR)与空间匹配系数,Doppler匹配系数,极化匹配系数,杂波脊斜率,信噪比(SNR),杂噪比(CNR)等的定量解析表达式.并与空时自适应处理(STAP)进行比较,从理论上分析得到了极化空时处理性能优于空时处理.特别在检测慢速运动目标时,新方法具有较强的稳健性.最后,仿真算例验证了模型的正确性.%A new polarization-space-time joint domain processing (PST-JDP) method is proposed,because it is difficult to suppress clutter and to detect slowly moving target in airborne radar. The method uses adequately the three-domain information which includes the polarization, space and Doppler frequency information of radar echo. It is shown that polarization information together with space and Doppler frequency information can be used effectively to significantly enhance the performance of clutter suppression in airborne radar. Signal model and adaptive algorithm model are established. Some new techniques, (i. e. ,covariance matrix eigendecomposition, spectral analysis and resolution grid method), are utilized for deriving the performance of PST-JDP. The main factors which affect on the performance of clutter rejection are the spatial, Doppler and polarized matching coefficient, and slope of clutter ridge, signal-to-noise ratio (SNR), input clutter-to-noise ratio (CNR). The new PST-JDP method performed significantly better than the traditional optimum space-time processing technology, especially in the case of the target slowly moving. Simulations demonstrate the correctness of models.
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