Patent ID: 9130671
Filing Date: 2015-09-08
Classification: H04B,H04J

Abstract:
1. An apparatus comprising: a light source to generate a first monitoring light to propagate over a fiber, the fiber configured to transmit data in at least one of data transmission wavelength bands; a first broadband light source (“BLS”) for outputting an incoherent light in a monitoring wavelength band that is different from the at least one of the data transmission wavelength bands, the incoherent light to be injected into the light source to generate the first monitoring light; a tunable band pass filter coupled to the BLS to pass one or more wavelengths of the incoherent light in the monitoring wavelength band to be injected into the light source; a coarse wavelength division multiplexer (“CWDM” couple between the tunable band pass filter and the fiber to propagate the first monitoring light over the fiber; a photo detector to receive a second monitoring light via the CWDM, wherein the second monitoring light includes the first monitoring light backscattered on the fiber, an optical circulator comprising a first port coupled to the first broadband source, a second port to route the incoherent light to inject into the light source, a third port to route the first monitoring light from the light source to the fiber, and a fourth port to route the second monitoring light from the fiber to the photo detector.