应用于谐振式光纤陀螺的双相位锁相放大器的设计

Applied to Resonator Fiber Optic Gyro Dual-phase Lock-in Amplifier Design

谐振式光纤陀螺(R-FOG)是利基于光学Sagnac效应实现高精度的转动检测惯性传感器件。在R-FOG系统中,陀螺信号的处理占有非常重要的地位。根据R-FOG系统中,光纤环形谐振腔的谱线宽度高达几十MHz以及RFOG输出信号具有弱信号、大噪声特点。设计了一种用于提取被噪声淹没的微弱信号的双相位锁相放大器,优点在于不需要进行相位调整。在对双相位锁相放大器各部分电路进行具体设计和分析的基础上,完成了对整体电路的性能测试。测试结果表明,研制的锁相放大器在载波频率为900 k Hz时,将整个电路应用于R-FOG系统中,解调出的信号效果良好,可以实现锁频要求。

Resonator fiber optic gyro （R -FOG） is a niche in the high-precision optical Sagnac effect of inertial sensors to detect rotation. In the R- FOG system,the processing of the gyro signal occupies a very important position. According to R - FOG system, the ring resonator fiber optic line width of up to several tens of MHz, and R - FOG output signal having a weak signal, the noise characteristics of the large. This paper presented a method for extracting weak signals were noise drowned dual phase lock-in amplifier,the advantage is that no phase adjustment. Based on the dual-phase lock-in amplifier for each of the specific portion of the circuit design and analysis, it tested the completion of the overall performance of the circuit. Test results show that the development of the lock-in amplifier when the carrier frequency is 900 kHz, the whole circuit is applied to R - FOG system, the demodulated signal to good effect, can be locked to achieve the requirements.