Transfer function of optical waveguide ring resonator in frequency domain for micro-optic gyro

Resonator micro optic gyro (R-MOG) is a high accuracy inertial rotation sensor based on the Sagnac effect. Optical waveguide ring resonator is the core-sensing element in R-MOG. According to the feature of the input signal, we established the transfer function of a Si-based ring resonator model in frequency domain for R-MOG with the coupled-mode theory. According to using the derived transfer function in the frequency domain, we analyzed the demodulation characteristics of R-MOG using Bessel function expansion based on laser frequency modulation spectrum technique. And we analyzed the relationship between the frequency modulation demodulation output signal and the resonant frequency deviation and obtained the best modulation coefficient applied in laser PZT drive. When the modulation coefficient M = 2, the maximum linear interval slope, the demodulation curve is the best.