利用相位中心偏移方位多波束来实现宽测绘带SAR成像

Implementing Wide-swath SAR Based on Displaced Phase Center Azimuth Multi-beam

该文提出了一种基于相位中心偏移方位多波束的宽测绘带星载SAR实现方案。通过在方位向上配置相位中心偏移的多个波束使雷达在一个脉冲周期内完成多个多普勒历程的信号采样,显著降低系统对脉冲重复频率的要求,实现宽测带SAR成像。针对卫星速度的非恒定性和不同波位所需PRF的多样性造成的方位信号非均匀采样,该方案采用了多通道信号重建技术来恢复均匀采样信号的算法。与采用高轨技术和分布式技术的宽测绘带SAR方案相比,这种方案的技术难度较小、易于实现。

A wide-swath SAR scheme based on displaced phase center azimuth multibeam is presented in this paper More than one azimuth sampling can be acquired during one pulse period in the SAR system with azimuth multibeam. Therefore, the pulse repetition frequency can be greatly reduced, which enables wide-swath SAR imaging. As the satellite velocity varies in different part of the orbit and PRF required for each view angle is different, the azimuth sampling is nonuniform in some orbit position. A signal reconstruction algorithm based on multi-channel sampling is proposed to eliminate nonuniform azimuth sampling. Compared with the wide-swath SAR based on high orbit satellite or distributed satellite, the proposed scheme is easier to implement.