高分辨无人机载SAR多模接收/激励子系统

为适应无人机载SAR侦察系统高分辨、大测绘带、微型化要求,接收/激励子系统采用了直接解调与去调频兼容工作方式,使系统基于100 MHz实时处理器实现最高达0.5 m分辨率多种工作模式,并具有大测绘带功能。采用了基于高速数字直读波形产生技术实现了发射信号和去调频信号的预失真补偿,结合接收通道失真的大闭环补偿,在大带宽时获得优于-40 dB距离峰值副瓣。采用了多重隔振和小型化结构设计实现了强环境适应性和振动条件下高频率稳定度。

Multi-modes Receiver and Exciter Subsystem for High Resolution UAV SAR

In order to fulfill the requirements of high resolution,wide swath and small size of the UAV SAR,direct demodulation and dechirp receiving mode are adopted simultaneously in the receiver and exciter subsystem,wherefore,up to 0.5 m resolution and wide swath are achieved based on 100 MHz real-time processor in the UAVSAR system.To implement the pre-distortion compensation of exciter and dechirp signal,high-speed direct readout digital waveform generation is adopted,Then sidelobe suppression level better than-40 dB in wideband mode is attained.Using multiple vibration isolation and miniature construction design technology,the system has high frequency stability and good environment adaptability in the condition of vibration.