雷达信号采集动态性能影响因素分析

The Analysis of Dynamic Performance Factors in Radar Signal Acquisition

文章针对星载雷达数据采集中高速数模转换系统有效位普遍较低而致雷达成像分辨率变低的问题,对高速信号链路中影响信号质量的因素进行了分析,找到了信号动态性能的影响因素。这些因素包括时钟抖动、调理电路噪声、数模转换器本身的性能指标和温度变化等。通过对时钟抖动和电源噪声的抑制、以及良好的接地和选择低噪声的高速运算放大器等措施,提高了系统的信噪比,从而提高数据采集的有效位。根据信噪比与有效位计算公式,分别计算了时钟抖动、调理电路噪声、温度等因素对有效位的影响。经过计算可知,通过这些改进,可使得系统的有效位达到11.94位。这些措施对高精度的雷达信号采集系统有一定的参考价值,可应用于星载雷达载荷领域。

The ENOB is generally lower in high speed AD convertion,this problem caused in lower radar imaging resolution.The influence of radar signal acquisition on the dynamic performance is analyzed,these factors include clock jitter,conditioning circuit noise,the features of A/D converter and temperature drift. This paper calculated the effects of clock jitter,conditioning circuit noise and temperature drift separately according to the ENOB formula.The ENOB were achieved 11.9bits by improving these factors. These measures have certain reference to radar signal acquisition,can be used in radar satellite.