High-Squint SAR Imaging Technique Based on Multi-Chip DSP

Abstract

High-speed digital signal processor (DSP) can solve the time-consuming issue of synthetic aperture radar (SAR) imaging for promoting its application in both military and civilian communities. In this paper, an entire processing chain using two multi-core DSPs for high-squint SAR data imaging, including azimuth filtering and decimation, improved polar format algorithm (PFA), phase gradient autofocus (PGA), image quantization, and return for display, is proposed. The multi-chip DSP architecture can improve the computational efficiency of high-squint and high-resolution SAR imagery generation. Finally, measured SAR imaging results demonstrate the algorithm chain and its parallel architecture that each multicore DSP TMS320C6678 can process the image of 4096*2048 pixels within 1.25 seconds. Moreover, while two chips cooperate in a ping-pong manner, two frames will be obtained after 1.53 seconds, enhancing the processing efficiency by 61 % approximately.