Experimental proving of methods for estimation of optical fiber curvature distribution

The methods for estimation of optical fiber curvature distribution based on reflectometric measurement at two wavelength and using polarization reflectometry method were proposed. The study was carried out on a mock-up based on optical fiber that complies with ITU-T G.657.A1/G.652.D recommendations. When implementing a method based on measuring the distribution of the difference in attenuation coefficients at two wavelengths of 1550 and 1650 nm, the possibility of estimating bending radius of less than 30 mm was demonstrated. When implementing a method based on the birefringence distribution measuring using a polarization reflectometer, the possibility of estimating bending radius from 35 to 75 mm was demonstrated. For a prototype polarizationreflectometer, the factors affecting the estimation accuracy and the range of controlled values are determined, and conclusions concerning required upgrade options are made.