数字闭环光纤陀螺死区机理分析

Analysis on dead-band mechanism of digital closed-loop FOG

结合工程实际,对基于集成光学多功能芯片的数字闭环光纤陀螺中的死区机理进行理论分析,并进行了实验验证。相位调制器的模拟驱动电压信号在数字反馈阶梯波复位作用下能产生不同的工作模式,探测器的输出微弱信号因此受到幅值和相位均不同的电子串扰。以方波调制和四态波调制为例,研究了光纤陀螺中电子串扰的作用方式、电子串扰的转换方式和形成死区的过程等问题。在上述基础上,根据需要设计了专门的可编程的光纤陀螺高速数据采集电路,对死区机理进行了研究试验。最后还从优化陀螺电路印制板设计和优化信号调制解调算法等方面进行阐述,以解决数字闭环光纤陀螺死区问题。

Incorporating with engineering applications, the mechanism of the dead band in a digital closed-loop fibre optic gyroscope （FOG） was theoretically analysed. The driving signal of phase modulator could couple into the weak signal output from the detector, and generated electronic crosstalk. Based on the square-wave modulation and four- state wave modulation, the operating mode of the electronic crosstalk and how it resulted in dead band in FOG was described, and the analysis was verified by experiments. The paper also discussed the method of optimising the print circuit board design and the demodulating arithmetic in order to overcome the dead band in FOG.