地面微动目标激励的雷达回波信号的微多普勒调制,反映了该目标的独有特征,因此可用于目标检测与识别。合成孔径雷达(synthetic aperture radar,SAR)对地面振动目标检测时,回波信号中不可避免地包含大量地杂波,给其微多普勒信息提取造成很大困难。为此,提出一种基于双通道SAR/DPCA杂波抑制的地面振动目标的微多普勒信息提取方法。首先利用双通道DPCA技术在复原始数据域对消地杂波以获取振动目标的回波信息,然后详细推导了杂波对消后微多普勒频率的参数化表达式。最后,通过数值仿真验证了该方法的有效性和正确性。
The micro-Doppler modulation induced by mechanical vibration or rotation of structures on a ground target is to be regarded as a unique signature of this target,which can be used for target detection and identification.It's well known that the returned radar signal not only includes the micro-motion target echo but also the strong ground clutter,so it's difficult to extract its micro-Doppler information.In order to solve this problem,the method of micro-Doppler extraction based on dual-channel SAR/DPCA technique is presented.First,the dual-channel DPCA technique is utilized to cancel the ground clutter in the raw-data domain and preserve the echo of the vibrating target,and then the mathematical expression of micro-Doppler frequency is deduced in detail.Finally,a computer simulation combined with the time-frequency analysis is given to verify the validity of the theoretical analysis and the proposed method.