一站固定式双基FMCW SAR地面振动目标检测与特征提取

Vibrating Ground Target Detection and Feature Extraction of One-stationary Bistatic Frequency-modulated Continuous-wave Synthetic Aperture Radar

地面目标的微小运动是目标本身独有的特性,可用于目标的分类与识别。论文对一站固定式双基FMCW SAR地面振动目标检测与特征提取方法展开研究,采用相位中心偏置天线(DPCA)技术进行杂波抑制,进而检测出地面振动目标。对回波信号分析表明,经DPCA杂波抑制后回波信号中存在一个随慢时间变化的包络项,称为慢时间包络(STE),该项将影响振动目标微多普勒(m-D)时频曲线的能量分布,导致无法获取完整的振动目标mD时频曲线;进一步地,利用STE项与振动特征之间的关系,可实现振动目标的特征提取。仿真实验验证了理论分析结果及特征提取方法的有效性。

One of the unique characteristics of a ground target is its micro-motion, which can be used for target classification and identification. In this study, methods for vibrating ground target detection and feature extraction of the one-stationary bistatic frequency-modulated continuous-wave Synthetic Aperture Radar（SAR） are studied. The Displaced Phase Center Antenna（DPCA） technique is adopted to suppress the ground clutter, allowing the ground-vibrating targets to be detected. Analysis of the received signal indicates that the DPCA processing results in a slow time-varying envelope, known as the Slow Time Envelope（STE）. The STE has a direct effect on the micro-Doppler time-frequency curve, which therefore cannot be obtained unbroken.Furthermore, vibrating features are extracted by utilizing their relationship with the STE term. Finally, some simulations are provided to validate the theoretical derivation and effectiveness of the proposed extraction method.