System and method of stabilizing the scale factor shift in fiber optic

Abstract

A system and method for providing scale factor stabilization of a broadband light source used in fiber optic gyroscopes is provided. A primary bandpass filter is positioned in the propagation path of the light emitted by the broadband light source to narrow the spectral width of the optical signal transmitted to the fiber optic gyroscope, which reduces the centroid wavelength shift resulting when the broadband light source is exposed to ionizing radiation and other harsh environmental conditions. The filtered optical signal is then passed through the fiber optic gyroscope, where the filter optical signal is processed to measure the amount of rotation of the fiber optic gyroscope. The scale factor stabilization system further includes the spectral monitor array arranged to perform direct optical wavelength measurements of the filtered optical signal to determine whether a scale factor shift in the optical signal has occurred. When a scale factor shift is detected, the detected scale factor shift is used in a compensation algorithm to correct the scale factor of the optical signal. By monitoring the scale factor shift and adjusting the values measured by the fiber optic gyroscope in accordance with the detected scale factor shift, the accuracy of the fiber optic gyro can be improved to a fraction of a part-per-million.