Interferometric filtering of the excess relative intensity noise of the broadband source of a fiber optic gyroscope

Abstract

We present a new method of reduction of the excess RIN (relative intensity noise) of the broadband source of a fiber-optic gyroscope (FOG). It is based upon the use of an interferometric filter which reduces the excess RIN at the proper frequency of the sensing coil. We demonstrate that a fiber-optic ring resonator can provide a RIN power density reduction (PSD) of 18dB allowing the FOG to operate near the photonnoise limit.