合成孔径雷达相干与非相干干扰性能分析

推导了合成孔径雷达(synthetic aperture radar,SAR)非相干干扰、一维卷积干扰和二维相干干扰成像前后的功率表达式,建立了成像处理增益(imaging processing gain,IPG)关于SAR系统参数和干扰区面积的关系模型和干信比(interference-signal power rate, ISR)方程。分析结果表明,在一定范围内,相干干扰的IPG随干扰区面积增大而减小,当一维卷积干扰的干扰区宽度大于SAR成像前距离分辨率时,其IPG与非相干干扰相同,当二维相干干扰的干扰区宽度和长度分别大于SAR成像前距离分辨率和方位分辨率时,其IPG与非相干干扰之比等于方位过采样率,3种干扰的ISR与IPG具有相同特性。仿真验证分析了所得出的结论。

Performance analysis of coherent jamming and non-coherent jamming against SAR

The theoretical expressions for the power before and after imaging processing of non-coherent jamming, 1D convolution jamming and 2D coherent jamming against synthetic aperture radar (SAR) is deduced, and the imaging process gain(IPG) model and the interference-signal power rate (ISR) about SAR system parameters and jamming areas are established. The theoretical analysis results demonstrate that to a certain extent, the IPG and ISR of coherent jamming decrease as the jamming area increases, and that if the interference region range width of the 1D convolution jamming is greater than the range resolution before SAR imaging, its IPG and ISR are the same as that of non-coherent jamming, and the results also show that if the interference region range width and azimuth length of the 2D coherent jamming are greater than the range resolution and azimuth resolution before SAR imaging, the ratio of IPG and ISR between it and non-coherent is equal to the azimuth over-sampling ratio. Simulation corroborates the availability of theoretical analysis results and conclusion.