SAR实时成像系统的快速定点仿真验证技术

SAR实时成像处理系统的定点化优化能够减小系统存储规模、提高系统运算速度，是降低系统功耗、减小系统规模、提高实时性的有效方法.本文以CS成像算法为例，分析并统计了算法的运算量，针对其核心运算--FFT进行了定点化优化，选择基-22FFT算法，设计了合理的定标策略.采用SystemC语言对整个SAR成像系统进行了系统级快速仿真和验证，真实模拟了FPGA系统的实现结果.对16 384×16 384大小的点阵数据和面目标数据采用24 bits的字长进行了成像仿真，仿真结果满足系统指标要求. 

Fast Fixed-Point Simulation Technology for SAR Real-Time Imaging System

Fixed-point processing optimization can reduce the storage, improve the computing speed, is an effective way to reduce power consumption and storage, improve the real-time performance of synthetic aperture radar (SAR) real-time imaging system. Taking the well-known chirp scaling (CS) algorithm as example, the count of computations was analyzed in this paper. Radix-2² algorithm of fast Fourier transform (FFT) as the main part of computations was adopted for fixed-point processing optimization, realized through a reasonable scale strategy with SystemC. Thus rapid system-level simulation of CS algorithm was implemented to provide a standard basis for FPGA implementation. Finally, test images from the raw lattice and area target data (16 384×16 384) were analyzed using fixed-point CS algorithm with 24 bits input word lengths. The simulation results meet the requirements of system indicators.