【作者】 李卓； 陈杰； 李春升； 周荫清；

【Author】 Li Zhuo Chen Jie Li Chunsheng Zhou Yinqing (School of Electronics and Information Engineering BeiHang University Beijing 100191 China)

【机构】 北京航空航天大学电子信息工程学院；

【摘要】 电离层是地球空间环境的重要组成部分,对卫星通信、导航定位和微波遥感等系统产生重要的影响。本文探讨了基于星载高频合成孔径雷达(HF-SAR)系统获取高分辨率的顶层电离层不规则体全球分布的可行性。本文给出了星载HF-SAR系统的参数设计和性能分析,建立了星载HF-SAR和不规则体相对运动的空间几何模型,总结了星载HF-SAR回波信号特点和成像处理的难点。本文基于等效斜距模型,提出了一种能够校正电离层延迟脉冲展宽效应的二维时域频域混合相关成像处理算法。通过计算机仿真成像,验证了该算法的有效性和星载HF-SAR系统的性能。更多还原

【Abstract】 The ionosphere is an important component of the geospace,which has significant impact on satellite communication,navigation,remote sensing etc.The feasibility of an advanced ionospheric radio explorer with spaceborne high-frequency synthetic aperture radar(HF-SAR) was investigated in this paper,which would be utilized to acquire the high resolution irregularity distribution map of topside ionosphere at global scale.The system parameters and performance analysis of spaceborne HF-SAR was presented.The geometric model for description of relative movement between radar and irregularity was established.The characteristic of spaceborne HF-SAR signal was analyzed,and the difficulty of spaceborne HF-SAR signal processing was construed.An image formation algorithm based on two dimension time-frequency domain correlation is presented,which has the capability to compensate ionospheric path delay effect.Computer simulation results were given,which verify the effectiveness of the image formation algorithm and the performance of the SAR system.更多还原