Optical fiber line characteristic analysis apparatus and analysis method thereof

摘要

A test pulse is generated from a first and a second test light beam pulse with different wavelengths, with a predetermined time difference applied between the first and the second test light beam pulse. A circulator inputs the test pulse to a trunk fiber of a measurement target fiber line. A reflected light is extracted which is output from an input end of the trunk fiber. A filter extracts stimulated Brillouin backscattered light. A receiver receives and converts the scattered light into an electrical signal. A processing device carries out the signal to determine in which of N branched fibers the stimulated Brillouin scattered light is generated, while varying a time difference between the first and the second test pulse.

主权项

1. An optical fiber line characteristic analysis apparatus that analyzes characteristics of a test target optical fiber line comprising a trunk optical fiber a first end of which is split into a plurality of branched optical fibers by an optical splitter with splitting ends to which respective first ends of the branched optical fibers are optically coupled, the apparatus comprising:
test light beam pulse generator configured to generate a first test light beam and a second test light beam with different wavelengths, and to generate a first test light beam pulse and a second test light beam pulse from the first and second test light beams with any time difference applied between the first test light beam pulse and the second test light beam pulse and to synthese the first and second test light beam pulses; a plurality of optical reflection filters each disposed at a second end of a corresponding one of the branched optical fibers in the measurement target optical line to reflect light with the wavelengths of the first and second test light beams, while allowing light with other wavelengths to pass through; an optical circulator configured to input the test light beam pulses generated by the test light beam pulse generator to the trunk optical fiber in the measurement target optical fiber line and to extract a reflected light output from an input end of the trunk optical fiber; an optical filter configured to extract stimulated Brillouin backscattered light from the reflected light; an optical receiver configured to receive the scattered light extracted by the optical filter and to convert the scattered light into an electrical signal; a converter configured to convert the electrical signal into a digital signal; and an arithmetic processing device configured to measure the stimulated Brillouin backscattered light based on the digital signal and to analyze characteristics of the measurement target optical fiber line, wherein the arithmetic processing device measures the stimulated Brillouin backscattered light while varying a time difference between the first test light beam pulse and second test light beam pulse generated by the test light beam pulse generator.