Moving Target Indication for Dual-Channel Circular SAR/GMTI Systems

Sensors

Laihe Wang¹  Wu Wang¹  Yueli Li¹  Daoxiang An¹ 

[1] College of Electronic Science and Technology, National University of Defense Technology, Changsha 410073, China;

关键词: dual-channel circular synthetic aperture radar;    moving target detection;    channel registration;    channel equalization;    clutter suppression;   

DOI  :  10.3390/s20010158

来源: DOAJ

【 摘 要 】

In a dual-channel circular synthetic aperture radar (CSAR) and ground moving target indication (GMTI) system, the antenna baseline is not parallel with the flight path due to a yaw angle. The angle causes a varying group-phase shift between the dual-channel signals and therefore degrades the correlation between the image pair. Therefore, the group-phase shift needs to be removed before channel equalization. To resolve the problem, the interferometric phase term was deduced and analyzed based on the geometry of a dual-channel CSAR system. Then, the varying phase term with respect to the Doppler frequency and the varying group-phase shift over the range were compensated for in the channel registration. Furthermore, blind channel equalization, including two-dimensional calibration and amplitude equalization, was applied to eliminate the amplitude and residual phase differences between the channels. Finally, the amplitude image obtained using a displaced phase center antenna (DPCA) was multiplied by the phase image obtained with along-track interferometry (ATI) to detect moving targets. The experimental results verified the effectiveness of the method for both uniform and non-uniform clutter suppression.

【 授权许可】

Unknown