A new channel balancing algorithm in image domain for multichannel SAR-GMTI system

Clutter suppression is a key problem for multi-channel SAR ground moving target indication (GMTI), which is sensitive to the correlation among channels. For real multichannel SAR-GMTI system, there are inevitably slight differences in the frequency response and antenna patterns among channels. Therefore, the correlation of channels will be worsen and channel balancing is a crucial step to obtain a satisfactory result for multichannel SAR GMTI. Since the SAR imaging is a linear process, no matter what cause the channel imbalance, they will be transferred into the image domain. A new channel balancing algorithm is proposed to calibrate the magnitude and phase imbalance in the image domain, without any preprocessing for the SAR image formation. Finally, the effectiveness of the proposed algorithm is demonstrated via the real data.