基于ATI技术和Radon变换的振动目标微多普勒提取

Micro-Doppler Extraction of Vibrating Target Based on ATI Technique and Radon Transform in SAR

针对地杂波背景下地面振动目标的时变微多普勒特征提取问题,提出了一种基于距离向压缩数据域双通道ATI干涉和Radon变换的提取方法.ATI相位对消用于抑制地杂波,获取振动目标的干涉信号,其在距离向压缩数据域呈现为沿方位向的直线;Radon变换则用于检测这些微弱直线分量,并确定它们所在的距离单元.详细推导了目标沿不同方向振动引入的微多普勒参数化表达式.与单通道模式相比,该方法无需补偿雷达平动引起的多普勒频移,且可有效检测沿方位向振动的目标,其微多普勒谱的显著特征是呈非周期性变化.数值仿真验证了该方法的正确性和有效性.

Aiming at extracting the time-varying micro-Doppler feature of the vibrating target in ground clutter environment,the method of micro-Doppler extraction based on dual-channel ATI technique and Radon transform is presented.The ATI technique is utilized to suppress ground clutter and obtain the interferometric signal of the vibrating target,which is presented as a straight line along the azimuth direction in the range-compressed data domain.The Radon transform is utilized to detect the weak straight line and find out which range cell it locates at.And the mathematical expressions of micro-Doppler with different vibrating directions are derived and discussed in detail.Compared with the single-channel situation,it is no need to compensate for the Doppler shift caused by the radar＇s translation,and the target vibrating along the azimuth direction could be effectively detected,whose micro-Doppler presents remarkably nonperiodic feature.Simulated results verify the accuracy and availability of the proposed method.