基于自适应波形设计的天基雷达目标检测方法

针对天基雷达检测海面目标时杂波特性复杂、场景变化迅速和信杂比低的问题，文中提出一种基于波形自适应设计的目标检测方法。这种方法将每个驻留时间分拆为若干个子驻留，在第1个子驻留上发射线性调频脉冲，并进行预检测和杂波协方差估计。在后续子驻留中采用多粒子滤波技术对杂波协方差进行动态更新，以适应天基雷达杂波的快速变化。进而在后续子驻留中利用平均平方优化技术自适应的设计波形，并进行主成分分析和广义似然比检验，以提高信杂比和实现恒虚警率检测。最后，文中将海杂波建模为复合高斯过程、将目标建模为若干个具有确定但未知散射幅值的散射体，并进行仿真实验。结果表明，在尖峰性海杂波环境和天基监视雷达配置条件下，用这种目标检测方法实现可靠检测所需的信杂比降低约9dB，可有效改善对弱小目标的检测效果。

Target Detection Based on Adaptive Waveform Design for Space Based Radar

To resolve problems of complicated clutter, fast varying scenes, and low signal clutter ratio (SCR) in application of target detection on sea for space based radar (SBR), a target detection approach based on adaptive waveform design is proposed. First, complicated sea clutter is modeled as compound Gaussian process, and a target is modeled as some scatterers with deterministic unknown reflectivity. Second, every dwell duration of radar is divided into several sub dwells. Regular linear frequency modulated pulses are transmitted at sub\|dwell 1, and the received signal at this sub dwell is used to estimate clutter covariance matrices and pre detect targets. Estimated matrices are updated at every following sub dwell by using the multiple particle filtering technique to cope with fast varying clutter scenes of SBR. Furthermore, waveform of every following sub dwell is designed adaptively according to the mean square optimization technique. Finally, principal component analysis and generalized likelihood ratio test is used to improve SCR and implement property of constant false alarm rate respectively. Simulation results show that, considering configuration of SCR and condition of complicated clutter, SCR for requisite for reliable detection by use of this target detection approach reduced by about 9dB .Therefore, the work in this paper can markedly improve radar detection performance for weak targets.