Method and system for differentiating macro-bend losses from splice and connector losses in fiber-optic links

摘要

The method includes generation of modulated optical pulses and scrambling the state of polarization of the modulated optical pulses to random states of polarization. The modulated optical pulses are injected in at least one test fiber and Rayleigh backscattered optical pulses are received and split by a polarization beam splitter into two orthogonal optical components. The power of each optical component is measured and discrete values of polarization dependent loss as a function of distance along the fibre are calculated. Macro-bends and stresses are identified by analysing peaks in plots of traces of the values of polarization dependent loss. The macro-bend loss events are differentiated from the splice and connector loss events. Electrical signals corresponding to backscatter may be synchronously resampled and filter to improve the signal-to-noise ratio. Sensitivity may be increased by shifting the optical carrier wavelength from O-band to U-band. Each discrete value of the polarization dependent loss may be calculated from a logarithm of a ratio of the two measured powers.