Patent ID: 8873960
Filing Date: 2014-10-28
Classification: H04B,H04J,H04Q

Abstract:
1. A method for detecting faults and their locations in an optical path between an optical line terminal (OLT) and optical network units (ONUs) of a passive optical network (PON), comprising: forming a maintenance optical link through the PON between the OLT of the PON and a collocated ONU, wherein the OLT and its collocated ONU are each connected to an optical splitter; sending a ranging request from the OLT to the collocated ONU; in response to the ranging request, receiving a ranging burst signal over the maintenance optical link, wherein the received ranging burst signal includes at least a fault analysis detection pattern (FADP); and analyzing the FADP in the received ranging burst signal by auto-correlating the FADP signal with an expected FADP signal, wherein an uncorrelated event measured through the auto-correlation is indicative of a fault in the optical path of the PON and an occurrence time of the uncorrelated event is indicative of a location of the fault in the optical path.