Range cell migration correction analysis of one-step and two-step motion compensation for millimeter-wave airborne SAR imaging

作者：Wang, Guanyong; Zhang, Lei^*; Li, Jun; Hu, Qingrong

来源：EURASIP Journal on Advances in Signal Processing, 2016, 2016(1): 115.

DOI：10.1186/s13634-016-0416-1

• Synthetic aperture radar (SAR)
• Motion compensation (MOCO)
• Millimeter-wave (MMW)
• One-step MOCO

Conventional two-step motion compensation (MOCO) method is widely adapted for airborne synthetic aperture radar (SAR) imaging due to its conciseness combining with the SAR focusing procedure. For two-step MOCO, range-independent compensation is processed before range cell migration correction (RCMC), and the range-dependent phase correction is implemented after RCMC. However, the accuracy of RCMC would be seriously decreased by the residual range-dependent phase, which is a fatal problem for high-resolution millimeter-wave (MMW) SAR imaging. In this paper, an extensive investigation on the RCMC accuracy is provided by establishing an accurate formula expression between the range cell migration error and the residual range-dependent phase error. One-step MOCO-based SAR imaging algorithm is investigated by compensating the range-dependent motion error before RCMC, so the presence of range cell migration error would be significantly suppressed. What is more, a modified azimuth match filtering (AMF) function is given by precise topography and aperture-dependent motion compensation (PTA) method to overcome the residual azimuth-dependent phase error in the azimuth compression stage. Both simulated and real-measured MMW SAR data sets are used to validate the analysis for high-resolution airborne SAR imaging.

• 出版日期2016-11-10
• 单位中国航天科工集团公司; 西安电子科技大学; 北京无线电计量测试研究所