Patent ID: 8693866
Filing Date: 2014-04-08
Classification: H04B,H04Q

Abstract:
1. A method for detecting fiber faults in a wavelength division multiplexing (“WDM”) optical access network, the method comprising: launching a test signal into a fiber trunk line linking a central office (“CO”) to a remote node (“RN”) of the WDM optical access network, the test signal having a first wavelength and generated by an optical time domain reflectometry (“OTDR”) unit at the CO to simultaneously test a plurality of fiber access lines linking the RN to a corresponding plurality of customer premises (“CPs”) for a fiber fault; separating the test signal from downstream WDM signals also delivered on the fiber trunk line to the RN; power splitting the test signal at the RN into a plurality of access line test signals; recombining each of the access line test signals with a corresponding one of the downstream WDM signals onto a corresponding one of the fiber access lines; receiving test signal reflections at the CO from the fiber access lines as a reflection signature, wherein the test signal reflections each have the first wavelength; and analyzing the reflection signature to identify a location of the fiber fault.