Patent ID: 6512610
Filing Date: 2003-01-28
Classification: G01M

Abstract:
A multi-branch optical network testing method comprising the steps of:inputting optical pulses to a branch point at which a multi-branch optical network branches off by a plurality of optical lines; receiving response beams corresponding to mixture of reflection beams which are produced by reflecting the optical beams at selected portions of the optical lines respectively; performing logarithmic conversion on waveform data corresponding to electric signals, which are produced by converting the response beams; performing calculations on the logarithmically-converted waveform data to produce an approximation line; comparing the logarithmically-converted waveform data with the approximation line to detect Fresnel reflection points on the waveform data; using the Fresnel reflection points as split points to split the waveform data to a number of ranges; performing separative analysis on each of the ranges to calculate attenuation constants with respect to each of the optical lines; storing the attenuation constants in a storage device in connection with each of measurement times; and determining a fault occurrence time, a fault occurrence line and a fault occurrence distance with respect to a fault that occurs in the multi-branch optical network having the optical lines on the basis of the attenuation constants which are repeatedly calculated every prescribed time and stored in the storage device.