环形激光陀螺仪随机误差模型的研究

Investigation on random error model of ring laser gyro

为了减少陀螺仪的误差并提高其精度，需要对陀螺仪误差进行估算与补偿，因而建立了陀螺仪的随机误差模型。在环形激光陀螺仪（ＲＬＧ）随机误差模型分析方法中，有功率谱密度（ＰＳＤ）分析，时序ＡＲＭＡ模型，及Ａｌａｎ方差分析。Ａｌａｎ方差分析是在时域上对频率稳定性进行分析的一种通用方法。在Ａｌａｎ方差与ＰＳＤ之间存在定量的关系。通过分析Ａｌａｎ方差，可以分辨出存在于ＲＬＧ中的各种类型噪声。Ａｌａｎ方差分析比在频域上分析ＰＳＤ简单得多。该文用Ａｌａｎ方差对Ｌ－１环形激光陀螺仪进行了具体的分析，得到了存在于Ｌ－１环形激光陀螺仪中的各误差源。表明Ａｌａｎ方差是建立激光陀螺仪随机误差模型的一种很实用的方法。

Errors of inertial navigation systems are mainly caused by the errors of the gyros. The evaluation and compensation of errors of gyros is an important way to improve the precision of gyros. It is necessary to build the random error model of gyros. Several methods can be used to analyse random error model of ring laser gyro (RLG), such as power spectrum density (PSD), ARMA, and Allan variance. Allan variance is a tool to analyse the stability of frequency in the time domain. There is quantitative relationship between Allan variance and power spectrum density of noise. Various kinds of ring laser gyro noise can be extracted from the gyro data with Allan variance. It is simpler than to analyse PSD in frequency domain. L 1 RLG was analysed with Allan variance, and the errors which exist in L 1 RLG were given. It is shown that Allan variance is a practical tool to build the random error model of ring laser gyros.