FIBEROPTIC TRANSCEIVER WITH AN OPTICAL CIRCULATOR FOR OPTICAL TIME-DOMAIN REFLECTOMETERS

This paper describes the characterization of an improved fiber-optic t ransceiver for optical time-domain reflectometers (OTDR), The transcei ver employs an active fiber ring which has both transmitter and receiv er functions of OTDR, An optical circulator takes the place of the com bination of a 3-dB coupler and an optical isolator in the previously r eported system, Reflections from several length of cascaded fibers are measured to characterize the transceiver, Compared with the previous system, performance improvement of the transceiver with the optical ci rculator is achieved.