TheoH方差在光学陀螺随机误差分析中的应用

Application of TheoH Variance in Stochastic Error Analysis for the Optical Gyroscope Signal

针对用Allan方差方法进行随机误差分析时平均时间只能达到数据长度的一半,以致长相关时间下估计值的置信度较低的问题,本文提出运用高置信度的混合理论方差(Theo H方差)对光学陀螺进行分析。该方法结合光学陀螺的信号特征,通过改变混合点位置对偏差补偿函数进行改进,提高了估计准确度。运用多种方差估计算法对仿真信号以及光学陀螺实测数据进行分析。实验结果表明,Theo H方差辨识结果和实际的幂律谱噪声特性一致,且具有比Allan方差更高的估计精度。

To solve the problems that the averaging time of Allan variance can only reach half of total data length,and confidence at long averaging time is lower, according to the random errors properties of the inertial sensors at time and frequency domains, a new method for analyzing the random error properties of the inertial sensor based on high confidence and hybrid Allan variance （TheoH variance） is proposed, which can better adapt to the characteristics of optical gyroscope by changing the location of the transition point. The simulated random error of optical gyroscope and measured data of FOG start-up signal are analyzed with the TheoH variance and other variance analysis method. The results show that the estimation values of the TheoH variance are consistent with power-law noise,It can efficiently improve the confidence in the case of great averaging time, and its estimation accuracy is higher than the Allan variance, especially in long termτ- values.