Mathematical simulation of random coupling of polarization modes in single-mode optical fibers: II. Zero drift in a fiber ring interferometer

The zero drift and interference signal fading at the output of a fiber ring interferometer (FRI) Of large length made on the basis of a single-mode op tical fiber (SMOF) and intended to observe effects of general relativity ar e considered. Calculations are made by the method of numerical simulation u sing the model of random coupling between orthogonal polarization modes in a SMOF, which was proposed in the first part of the work. Numerical estimat es are made. In particular, it is shown that a FRI with a loop made of a we akly anisotropic SMOF, a superluminescent diode as a radiation source, and a linear polarizer placed between two beam-splitters (the most extensively used scheme of a FRI) does not provide the required accuracy even for a loo p area of 30 km(2). To increase the measurement accuracy, one should use a radiation source with a very small degree of polarization and a depolarizer of nonmonochromatic radiation in a FRI scheme.