机载高分辨聚束式SAR实时成像处理系统的FPGA实现

摘要

该文设计并实现了一个基于FPGA的机载高分辨聚束式SAR实时成像系统.该系统基于经典极坐标算法,在2维波束域完成运动误差估计及补偿,获得了良好聚焦的图像.文中详细阐述了将算法映射到FPGA实现的设计过程,给出了硬件系统平台的构成,并对系统资源、运算速度和成像结果进行了分析.在对实测机载聚束式SAR数据进行实时处理的实验中,FPGA工作在100MHz时,该系统11 s内可完成16384×32768点8位数据的成像处理.良好的实时成像结果验证了该系统的有效性和可靠性.%This paper designs and realizes a real-time image processor for SAR based on Field Programmable Gate Arrays (FPGA). The system is suitable for high resolution airborne spotlight mode SAR. The scheme applies the Polar Format Algorithm (PFA) first. Then the motion error phase is estimated and compensated in azimuth wavenumber domain. In this paper, the design approaches and the hardware system architecture are given and the resource usage, processing speed and image result are analyzed in detail. The real-time experiment results show that the system can process 1024 MB SAR raw data within 11 s, when the FPGA processing units work at 100MHz. The good experimental image also proves the validity and reliability of the proposed system.