Patent ID: 9140624
Filing Date: 2015-09-22
Classification: G01M,G01N

Abstract:
1. An optical time domain reflectometer (OTDR) system, comprising: a narrow line-width laser source comprising a thermoelectric cooler thermally coupled thereto; a modulator configured to modulate the narrow line-width laser source; a device configured to couple an output of the narrow line-width laser source and the modulator to a device under test and an input from the device under test to a photo-detector; and a controller configured to provide an input signal to the thermoelectric cooler to monitor and adjust a light output of the narrow line-width laser source in a wavelength locking feedback loop and to concurrently dither the thermoelectric cooler to adjust the light output of the narrow line-width laser source by about 0.02 nm and reduce coherence to reduce noise in OTDR traces to levels comparable to a wide spectrum laser source OTDR; wherein the narrow line-width laser source, the thermoelectric cooler, and the controller are disposed in a channel line card that is a channel transceiver connected to a multiplexer configured to combine a Dense Wavelength Division Multiplexing (DWDM) output from the modulator in an optical communication system and are collectively configured to perform OTDR functionality in the optical communication system.