METHOD OF MEASUREMENT OF EXCESSIVE LENGTH OF FIBRE OPTIC IN OPTIC MODULE OF OPTIC CABLE DURING CLIMATIC TESTS

摘要

FIELD: instrumentation.;SUBSTANCE: invention relates to the measuring equipment and is used to measure the excessive length of the fibre optic. Under this method the climatic chamber is used, in it negative temperature is set, and tested length of the fibre optic is held at this temperature for the set time period. Using the optical switch the pulse optical reflectometer of the reverse Rayleigh process is connected to the fibre optic, characteristic of the reverse Rayleigh process of the fibre optic is measured and recorded. Then it is disconnected, and the polarization pulse optical reflectometer is connected, it is used to measure and to record the polarization characteristic of the reverse scattering of the fibre optic, the characteristics are measured at other negative temperature, and based on the characteristics of the reverse Rayleigh process the attenuation coefficient is determined, and based on the polarization characteristics the length of pulsation of the fibre optic at different temperatures is determined, further change of the attenuation coefficient and length of pulsation of the fibre optic are calculated upon the temperature change, and local excessive length is determined for each section of the fibre optic.;EFFECT: increased sensitivity of measurements of the excessive length of the fibre optics.;1 dwg