重力卫星微加速度计位移检测电路噪声分析  

ANALYSIS OF NOISE OF DISPLACEMENT DETECTING CIRCUIT OF ACCELEROMETER FOR GRAVITY SATELLITE

作　　者：廖成旺[1] 李树德[1] 

机构地区：[1]中国地震局地震研究所

出　　处：《大地测量与地球动力学》2005年第2期82-87,共6页Journal of Geodesy and Geodynamics

基　　金："863"课题:中国地震科学卫星计划的预研与制定(2003AA134060)

摘　　要：对重力卫星微加速度计位移检测电路的输入输出关系进行了详尽的推导,对各种噪声进行了分析,并选取一组典型参数计算了具体数值。发现在所有位移噪声中,电阻的热噪声处于主导地位,而运算放大器的电压和电流噪声可以忽略。电阻的热噪声包含桥路电阻的热噪声和反馈电阻的热噪声。反馈电阻的热噪声可以通过减小反馈电容而减小,桥路电阻的热噪声则与反馈电容无关。位移检测电路的设计所能达到的最好水平是使其噪声处于桥路电阻的热噪声的水平,而桥路电阻的热噪声与探头结构参数、激励电压、温度和差动变压器品质因数等有关。Various type of noises of displacement detecting circuit of accelerometer for gravity satellite are analyzed and computed through deriving the relationship between input and output. It is found that the thermal noise of resistance is dominant while the contribution of operational amplifier is negligible. The thermal noise of resistance includes two parts: bridge resistance and feedback resistance. The latter can be lowered by decreasing feedback capacitance while the former is independent on feedback capacitance. The best noise level which we can acquire in the design of displacement detecting circuit is making it be the on thermal noise level of bridge resistance.However, the thermal noise of bridge resistance depend on parameters of sensor unit, exciting voltage, temperature and quality factor of differential transformer.

关 键 词：重力卫星 微加速度计位移检测电路 输入输出关系 噪声 电阻 探头结构参数 激励电压 温度 差动变压器品质 

分 类 号：P223[天文地球—大地测量学与测量工程]