摘要
应用于合成孔径雷达(SAR)的数字自动增益控制(DAGC)需要合适的增益门限才能有效地扩展接收机的动态范围,保证闭环系统稳定。针对应用于SAR的增益控制策略,在深入研究DAGC的单、双门限步进调整法的基础上,通过回波信号统计和系统性能分析,提出一种基于信噪比最优准则的门限设置方法,并给出双门限调整法的上下门限对比量的限定。数据域参数对比和仿真成像结果表明,该门限设置方法优于常规方法,更适用于SAR的自动增益控制。
In order to widen the dynamic range of synthetic aperture radar (SAR) receiver and ensure a stable system that tends to remain at a particular power output, appropriate threshold for digital automatic gain control (DAGC) must be chosen. This paper studied the single-threshold and double-threshold steptune method used in DAGC system of SAR in depth. Subsequently, we derived a threshold setting method based on optimized signal-to-noise ratio (SNR) for the both step-tune methods through statistic calculation and performance analysis, and also gave the ratio of high-threshold to low-threshold of double-threshold. In the end, we compared the parameters calculated from the sample signal of DAGC and the SAR data images, which show that the proposed method is better than the common method, and is adapt to SAR automatic gain control.
出处
《电机与控制学报》
EI
CSCD
北大核心
2008年第6期712-716,共5页
Electric Machines and Control
关键词
雷达
自动增益控制
步进调整
门限
radar
automatic gain control
step-tune
threshold
作者简介
陈曦(1982-),女,博士研究生,主要研究方向为合成孔径雷达回波信号的处理;
张平(1949-),男,研究员,博士生导师,主要研究方向为雷达测控与监测;
祁海明(1980-),男,博士,助理研究员,主要研究方向为合成孔径雷达系统与原始数据压缩。