Distributed measurement of polarization mode coupling in fiber ring based on P-OTDR complete polarization state detection

Abstract

Using a quaternion method, the polarization mode-coupling coefficient can be derived from three components of the Stokes vectors at three adjacent points along a fiber. A complete polarization optical time-domain reflectometry scheme for polarization mode coupling distributed measurement in polarization-maintaining fiber ring is proposed based on the above theoretical derivations. By comparing the measurement results of two opposite incident directions and two orthogonal polarization axes of polarization-maintaining fiber rings with different lengths, the feasibility and repeatability of the measurement scheme are verified experimentally with a positioning spatial resolution of 1 meter.

Analysis and removal of the second-order ghost coupling points in distributed multiple coupling point measurements

“…Polarization-maintaining fibers (PMFs) with a high internal birefringence can preserve a linear polarization state over a long fiber distance and have been widely employed in fiber optic communication and fiber optic sensors [1][2][3][4], such as optical fiber gyros [5][6][7][8], hydrophones, and measurement of strain and temperature [9][10][11][12]. In PMFs, because of the drawbacks associated with the manufacturing process and environmental perturbations, one polarization mode will be coupled into another orthogonal one, which is called distributed polarization coupling (DPC) [13].…”