基于光纤陀螺的残周期正弦拟合快速寻北法

在旋转调制寻北的基础上,提出少于一个旋转周期的快速寻北方法。建立了旋转调制寻北输出模型,介绍了三参数正弦拟合原理并推导出最小二乘估计算法的Cramer-Rao下限,最后设计了光纤陀螺残周期快速寻北实验。实验结果表明,残周期残缺程度越大,寻北时间会越短,北向偏角会越大;实验陀螺应用该方法,1/3个周期寻北精度为0.3°,1个周期寻北精度为0.009°,达到一个周期内快速寻北的目的。

Method of Partial Period Sine Wave Fit in Fast North seeking Based on Fiber Optic Gyroscope

Based on the principle of rotation modulation, a method of fast north seeking of partial period is proposed. First, an output model of north seeking is constructed. Then, three parameter sine wave fit is introduced, and the Cramer Rao lower bound for parameters estimation of sine wave is derived. At the last, a fast north seeking experiment of fiber optic gyroscope is designed. It is shown that the fewer the data of partial period are, the lower the accuracy of sine parameter estimation is. It is also concluded that the north seeking accuracies of 1/3 period and 1 period are 0.3° and 0.009° respectively by using the gyroscope. The method is valid to fast north seeking.