改善高精度数字闭环光纤陀螺阈值方法研究

研究了改善高精度光纤陀螺阈值的方法,提出导致阈值增大的原因是陀螺存在死区,而死区主要由调制解调电路中的电子交叉耦合干扰引起。对光纤陀螺仪的数字闭环传递模型进行了修正,增加了反馈通道对前向通道中探测器输出信号的电子交叉耦合干扰项,并利用此模型对死区进行了实时动态仿真,仿真分析结果基本和实验现象吻合。与采取随机调制的方法不同,本文主要采取优化电子电路设计、改善电路电磁兼容性等方法抑制死区,同样取得了较好的效果。提出了一种新的测试光纤陀螺仪的阈值方法,测试结果表明,优化设计后,陀螺仪的阈值与陀螺的噪声水平相当。

Method of reducing the threshold of the high-precision digital closed-loop fiber optic gyroscope

A novel method of reducing the threshold of the high precision digital closed-loop fiber optic gyroscope(DCFOG) is studied.The reason leading to the threshold increasing is proposed due to the gyroscope dead band which is mainly caused by the electronic cross-coupling interference in the modulation and demodulation circuit.The digital closed-loop transfer model for fiber-optic gyroscope is modified and the electronic cross-coupling interference from the feedback channel to the output signal of the detector in the forward channel is added.This model is also used to realize a real-time dynamic simulation for the dead band.The simulation results are basically consistent with experimental results.Unlike the random modulation method,this study inhibits the dead zone mainly by optimizing the electronic circuit and improving the circuit electromagnetic compatibility.We propose a new method to test the fiber optic gyro threshold.The results show that the gyroscope threshold is comparable to the noise level.