Patent ID: 9344188
Filing Date: 2016-05-17
CPC Classification: G01M,H04B,H04J,H04L

Claim Text:
1. A wavelength shifter module in a passive optical network (PON) configured to adapt an optical time domain reflectometry (OTDR) signal from an OTDR device for supervision of a drop section in the PON, the wavelength shifter module arranged in a fiber path between the OTDR device and a remote node (RN) and comprising: a first wavelength filter arranged to allow passage of light within a predetermined wavelength interval; a Raman wavelength shifter arranged to tune wavelengths of the filtered light to a range of wavelengths, wherein the range of wavelengths is selected based on information from one or more drop sections in the PON; a tunable filter tuned to allow passage of a pre-selected wavelength from the range of wavelengths from the Raman wavelength shifters, for monitoring of a specific drop section; and a pulse generation arrangement to erase an envelope of a main carrier of the pre-selected wavelength and remodulate light according to OTDR pulses; and a circulator to distribute the tuned light to a port in an optical distribution network (ODN) for monitoring the specific drop section.