Simulation of the limiting parameters of a polarimetric fibre-optic current sensor on a spun fibre

We report results of numerical simulation of limiting parameters of a spun-fibre-based polarimetric fibre-optic current sensor. A technique for modelling sensor parameters is described. Using the Poincaré sphere approach, we analyse the trajectory of a change in the polarisation state and the accumulation efficiency of the magneto-optical response of the sensor along the fibre. The main characteristics of the sensor, which depend on the polarisation parameters of the optical fibre, are presented: initial sensitivity, operating measurement range, its symmetry with respect to the zero current value, and shape of the sensor response curve in the measurement range. The correction conditions – linearization of the sensor response by flexural birefringence – are described. The influence of the spectrum width of the radiation source on the sensor response is modelled.