Open-loop operation experiments in a resonator fiber-optic gyro using the phase modulation spectroscopy technique

Abstract

A detection system in the resonator fiber-optic gyro is set up by the phase modulation (PM) spectroscopy technique. The slope of the demodulated curve near the resonant point is found to affect the ultimate sensitivity of the gyro. To maximize the demodulated signal slope, the modulation frequency and index are optimized by the expansion of the Bessel function and optical field overlapping method. Using different PM frequencies for the light waves, the open-loop gyro output signal is observed. The modulation frequency in this PM technique is limited only by the cutoff frequency of the LiNbO3 phase modulators, which can reach several gigahertz. This detection technique and system can be applied to the resonator micro-optic gyro with a less than 10 cm long integrated optical ring.

Analysis of temperature effect in fiber optics ring resonator based on photonic crystal fiber

“…M a n u s c r i p t 4 By computing the Eq. (4), we can get the shift in effective mode index due to the stress-induced change in refractive index for a temperature variation T  .…”

“…It includes the merits of interferometric fiber optic gyroscope (IFOG), and also fulfils the requirements of small volume, low cost and full solid-state [2][3][4]. Recently, various schemes to further enhance the performance of RFOG have been proposed [5][6][7][8].…”

The characterizations of polarization in resonator integrated optic gyroscope

“…If the close-loop controlling method (Hotate and Harumoto 1997) is adopted to examine the shift of the resonance dip, the influence of coupling outside the cavity can be ignored. The coupling outside the cavity may introduce error in the output of the gyro when the open-loop controlling method (Zhang et al 2006) is adopted, because the output of the gyro controlled by open-loop method is linearly proportional to the optic intensity at the operation point.…”

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

“…Several groups have researched and proposed different R-MOG schemes [4][5][6][7][8] . There are two main open-loop detection methods: the laser frequency modulation (FM) [9,10] and phase modulation (PM) [11,13] .In the PM spectroscopy technique, the modulation signal and the feedback signal are separated. But the modulation signal and the feedback signal is simultaneously applied to the laser in the FM method.…”