惯性元件再平衡回路噪声整形机理研究

Noise shaping mechanism of rebalancing loop for inertial component

推导出检测噪声传递函数和驱动噪声传递函数,并分析检测噪声传递函数幅频曲线转折频率、直流增益、单位增益频率和高频增益.结果表明,检测噪声传递函数具有低频衰减、高频放大的特征.以石英挠性加速度计为例,分析摆性、检测结构增益、检测电路增益和转动弹性系数对检测噪声传递函数的影响.结果表明,增大摆性、检测结构增益以及检测电路增益可以在全频段减小检测噪声传递函数的幅值,减小转动弹性系数可以在低频段减小检测噪声传递函数的幅值.仿真分析结果验证了石英挠性加速度计检测噪声传递函数和驱动噪声传递函数的频谱特征,验证了摆性、检测结构增益、检测电路增益和转动弹性系数对检测噪声传递函数的作用机理,说明通过优化噪声传递函数可以减少惯性传感器的噪声.

The detection noise transfer function and driving noise transfer function were derived,and the turning frequency of amplitude frequency curve,DC gain,unit gain frequency,and high-frequency gain of detection noise transfer function were analyzed.Results show that the detection noise transfer function has the characteristics of low frequency attenuation and high frequency amplification.Taking the quartz flexure accelerometer as an example,the influence of pendulosity,detecting structure gain,detecting circuit gain,and rotational elastic coefficient on detecting noise transfer function were analyzed.Results show that the increase of pendulosity,detecting structure gain,and detecting circuit gain leads to the decrease of amplitude of detecting noise transfer function in all frequency bands;and the decrease of rotation stiffness makes the amplitude of detecting noise transfer function decrease in the lowfrequency band.The simulation and analysis results has verified the spectrum characteristics of the detection noise transfer function and the driving noise transfer function of the quartz flexible accelerometer,as well as the mechanism of swing,detection structure gain,detection circuit gain,and the rotational elastic coefficient on the detection noise transfer function,indicating that the noise of the inertial sensor can be reduced by optimizing the noise transfer function.