基于冗余计算约简的环扫SAR回波多GPU快速模拟

Computation Reduction Oriented Circular Scanning SAR Raw Data Simulation on Multi-GPUs

环扫SAR作为一种特殊工作模式雷达,在对地观测方面有着广泛应用。随着分辨率提高及测绘带宽增大,对环扫SAR成像精度提出了更高的要求。而快速的海量回波模拟方法能够对高精度成像算法设计、研究提供有力的支撑。本文给出一种基于多GPU(Graphics Processing Unit,图形处理器)的环扫SAR回波模拟方法,并在此基础上进行冗余计算优化,通过MPI(Message Passing Interface,消息传递接口)在多GPU上进行了实现,实验结果表明在使用4块GPU的条件下,经过冗余计算约简,并行效率提高2倍以上,硬件成本降低50%,相对传统CPU串行仿真提高350倍左右。

As a special working mode, the circular scanning Synthetic Aperture Radar （SAR） is widely used in the earth observation. With the increase of resolution and swath width, the simulation data has a massive increase, which boosts the new requirements of efficiency. Through analyzing the redundancy in the raw data simulation based on Graphics Processing Unit （GPU）, a fast simulation method considering reduction of redundant computation is realized by the multi-GPUs and Message Passing Interface （MPI）. The results show that the efficiency of 4-GPUs increases 2 times through the redundant reduction, and the hardware cost decreases by 50%, thus the overall speedup achieves 350 times than the traditional CPU simulation.