An Efficient Refocusing Method for Ground Moving Targets in Multichannel SAR Imagery

作者：Jingtao Ma, Xiang‐Gen Xia, Jiannan Wang, Haihong Tao, Guisheng Liao, Penghui Huang · 发表于：IEEE Geoscience and Remote Sensing Letters · 年份：2024 · DOI：10.1109/lgrs.2024.3437429 · 被引用次数：6 · 研究领域：Advanced SAR Imaging Techniques、Synthetic Aperture Radar (SAR) Applications and Techniques、Geophysical Methods and Applications

This letter proposes a fast Doppler parameter estimation and refocusing method for ground moving targets in a synthetic aperture radar (SAR) system. In the proposed method, after implementing the main-lobe clutter rejection by using the azimuth adaptive processing technique, the range-azimuth positions of smeared target scatterers can be obtained via the constant false alarm rate (CFAR) detection. Then, an autocorrelation function is constructed to transform a moving target signal into the time-frequency plane, where the target parameters can be precisely and efficiently estimated by applying the scaled fast Fourier transform (FFT). Finally, ground moving targets can be well refocused and relocated in a SAR imagery. Compared with the conventional methods, the target output SNR can be enlarged about 3 dB under the low SNR by using the proposed parameter estimation method.