Patent ID: 7881609
Filing Date: 2011-02-01
Classification: H04J,H04Q

Abstract:
1. An optical access system, comprising: a station unit having a working system station interface and an auxiliary system station interface; an optical communication cable having a working system transmission line connected to the working system station interface and an auxiliary system transmission line connected to the auxiliary system station interface; a terminal access unit having a working system terminal interface connected to the working system transmission line and an auxiliary system terminal interface connected to the auxiliary system transmission line; a first ranging signal generator that generates a first ranging signal that outputs from the working system station interface to the working system transmission line; a first loop circuit that transfers the first ranging signal received by the working system terminal interface from the working system transmission line to the auxiliary system terminal interface; a second loop circuit that transfers the first ranging signal, which is received by the auxiliary system station interface from the auxiliary system terminal interface via the auxiliary system transmission line, to the working system station interface; a first checker that checks a time from when the working system station interface transmits the first ranging signal until the working system station interface receives the first ranging signal; a second ranging signal generator that generates a second ranging signal that outputs from the auxiliary system station interface to the auxiliary system transmission line; a third loop circuit that outputs the second ranging signal, which is received by the auxiliary system terminal interface from the auxiliary system transmission line, to the auxiliary system transmission line from the auxiliary system terminal interface; and a second checker that checks a time from when the auxiliary system station interface transmits the second ranging signal until the auxiliary system station interface receives the second ranging signal.