TY - GEN
T1 - New method for residual amplitude modulation control in RFOG
AU - Descampeaux, M.
AU - Feugnet, G.
AU - Bretenaker, F.
N1 - Publisher Copyright:
© 2021 IEEE.
PY - 2021/1/1
Y1 - 2021/1/1
N2 - The passive Resonator Fiber Optic Gyroscope (RFOG) measures the angular velocity by tracking the resonances of two counter propagating probing beams shifted by the Sagnac effect. A light phase modulation is necessary to implement such a tracking, for instance by creating a frequency error signal to lock the frequency of a laser on one of the cavity resonance. It might be accompanied by a Residual Amplitude Modulation (RAM) at the modulation frequency, which constitutes an important limitation to the precision and stability of a resonance frequency measurement. To control the RAM, the classical method was popularized by Wong and Hall in 1985: a dedicated photodetector monitors the intensity of the light before entering in the cavity. The limit of this technique appears when using a phase modulator with an imperfect polarizer at its output following by an optical setup exhibiting polarization dependent losses (PDL). To overcome this problem, we propose a new method based on using a single photodetector generating two errors signals to counteract simultaneously on the laser frequency and the RAM. We demonstrate the effectiveness of our method in the case of fibered systems presenting PDL following a phase modulator without any output polarizer.
AB - The passive Resonator Fiber Optic Gyroscope (RFOG) measures the angular velocity by tracking the resonances of two counter propagating probing beams shifted by the Sagnac effect. A light phase modulation is necessary to implement such a tracking, for instance by creating a frequency error signal to lock the frequency of a laser on one of the cavity resonance. It might be accompanied by a Residual Amplitude Modulation (RAM) at the modulation frequency, which constitutes an important limitation to the precision and stability of a resonance frequency measurement. To control the RAM, the classical method was popularized by Wong and Hall in 1985: a dedicated photodetector monitors the intensity of the light before entering in the cavity. The limit of this technique appears when using a phase modulator with an imperfect polarizer at its output following by an optical setup exhibiting polarization dependent losses (PDL). To overcome this problem, we propose a new method based on using a single photodetector generating two errors signals to counteract simultaneously on the laser frequency and the RAM. We demonstrate the effectiveness of our method in the case of fibered systems presenting PDL following a phase modulator without any output polarizer.
U2 - 10.1109/ISS52949.2021.9619809
DO - 10.1109/ISS52949.2021.9619809
M3 - Conference contribution
AN - SCOPUS:85123734052
T3 - 2021 DGON Inertial Sensors and Systems, ISS 2021 - Proceedings
BT - 2021 DGON Inertial Sensors and Systems, ISS 2021 - Proceedings
A2 - Hecker, Peter
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2021 DGON Inertial Sensors and Systems, ISS 2021
Y2 - 29 September 2021 through 30 September 2021
ER -