【摘要】 作为用于高精度测量的姿态敏感器,星敏感器需要具备很高的星等灵敏度。对以光电转换技术为核心的星敏感器来说,光信号的传输及转换容易引入噪声,而成像器噪声则成为影响星等灵敏度的重要因素。为了提高星敏感器的星等灵敏度,结合系统信噪比判据,分析了成像器中的CCD组件噪声和电路噪声,推导出系统信噪比公式。并针对其中的暗电流噪声、逻辑驱动电路噪声、直流偏置驱动电路噪声和A/D转换电路噪声等主要噪声提出了相应的解决方案,经分析和测试,成像器噪声对星等灵敏度的影响是不容忽视的。采用适当的噪声抑制方案可有效提高星敏感器的星等灵敏度。更多还原

【Abstract】 As one of the high precision measure devices for working on attitude sensor,the star sensor needs high magnitude sensitivity.For the star sensor based on photoelectric technique,the transmission and conversion of optical signal can import noise,so image processor’s noise becomes important factor to influence the magnitude sensitivity of the star sensor.In order to improve the magnitude sensitivity of the star sensor,the mechanisms of CCD module and circle noises were analyzed,and the SNR formula of system in combination with the criterion of SNR was developed.Analysis of dark current noise,logical drive circuit noise,direct current drive circuit noise,and A/D conversion circuit noise were performed,and then a solution was proposed.Experimental results indicate that the influence of image preprocessor noise on magnitude sensitivity can not be neglected.更多还原