SBIR-STTR Award

We propose new techniques to reduce the degradation of the detected signal of a depolarized fiber gyroscope as a result of noise from the light source. Attempts have been made to reduce intensity noise in fiber gyroscopes that use polarization-maintaining fiber in the fiber coil. We will review the efficacy of these techniques and attempt to determine their theoretical limitations. In a depolarized fiber gyroscope, source phase noise is converted to intensity noise. This creates a noise that has not been addressed heretofore. We propose to examine techniques to also reduce this noise. The use of single-mode fiber in the sensing coil will significantly reduce the cost of the gyroscope by reducing the cost of the fiber in the sensing coils. The price of single-mode fiber is between 1/2 and 1/100 of the cost of polarization maintaining fiber. This has the largest impact on high performance fiber-optic gyroscopes where the length of the fiber in the fiber loop is large and the cost of the fiber is a large fraction of the cost of the gyroscope.