Title :
Signal-feedback induced intensity modulation in a fibre optic gyro system
Author :
Jin, W. ; Culshaw, B.
Author_Institution :
Dept. of Electron. & Electr. Eng., Strathclyde Univ., Glasgow, UK
fDate :
10/1/1992 12:00:00 AM
Abstract :
The characteristics of signal-feedback-induced intensity modulation of a laser diode in a fibre optic gyro system is investigated theoretically and experimentally. The effect of the feedback is to induce an additional modulation term in the laser output which has the same waveform as the Sagnac signal and is amplified in amplitude (maximum 16 dB). The influence of this intensity modulation on the performance of a two-dimensional frequency-division multiplexed gyro system is to introduce additional terms sin 2φsi and sin φsi cos φsj if detection is at the first harmonic of the bias modulation of gyro i, where φsi and φsj are Sagnac phase shifts in gyro i and gyro j, respectively
Keywords :
amplitude modulation; feedback; fibre optic sensors; frequency division multiplexing; gyroscopes; light interferometers; optical modulation; semiconductor junction lasers; 2D; AM; Sagnac phase shifts; Sagnac signal; amplitude amplified signal; bias modulation; fibre optic gyro system; first harmonic; frequency-division multiplexed gyro system; interferometric Sagnac signal; laser diode; laser output; signal-feedback-induced intensity modulation; waveform;
Journal_Title :
Optoelectronics, IEE Proceedings J
