基于Frank序列优化的大斜视SAR信号设计

Signal Optimization for SAR with Large Squint Angle Based on Optimized Frank Sequence

合成孔径雷达(SAR)基于距离压缩和方位压缩获得二维高分辨率,但应用于低飞大斜视平台时因飞行高度低、速度快和斜视角过大等因素难于获得良好成像性能。针对低飞大斜视SAR成像问题,从波形设计角度出发,基于循环算法对多相编码Frank序列优化,得到具有良好自相关特性的编码序列,在满足多普勒容限条件下,与合理的脉冲重复频率相结合,克服了多普勒模糊,提高了成像分辨率,实现了良好的成像性能。仿真分析证明优化后的Frank序列可应用于低飞大斜视SAR并提供良好成像性能。

Synthetic Aperture Radar（SAR） gets two dimensional high resolutions through range and azimuth compression,but it will have difficulty in imaging when the platform has low height,high speed and large squint angle. Corresponding to the imaging problem,Frank code sequence is optimized with Cyclic Algorithm and used as the transmitted signal. Good correlation performance of Frank sequence,combined with proper PRF,help the SAR eliminate Doppler ambiguity and enhance the resolution of imaging,finally good imaging performance is gotten. Simulation results testified the good imaging performance brought by the optimized Frank sequence and proper PRF value.