Patent ID: 7711268
Filing Date: 2010-05-04
Classification: H04J

Abstract:
1. A passive optical network system comprising: a station-side communication device; a plurality of subscriber-side communication devices; an optical splitter and a plurality of optical fibers connecting the plurality of subscriber-side communication devices to the station-side communication device, wherein the station-side communication device determines timing of transmitting a signal to the station-side communication device from the subscriber-side communication devices for communications between the station-side communication device and the subscriber-side communication devices, the station-side communication device comprising: a distance measurement request signal for measuring distances between said respective plural subscriber-side communication devices and the station-side communication device is transmitted to the plurality of subscriber-side communication devices, and response signals from the plurality of subscriber-side communication devices in response to the distance measurement request signal are received to calculate transmission delay times of optical signals from the subscriber-side communication devices; and while the transmission granting part is notifying the subscriber-side communication devices that distance measurement is carried out, when the signal detection part detects a break in a received response signal from one of the subscriber-side communication devices, the reset timing generation part sends a reset signal to the threshold control part, and then the threshold control part executes reception of a response signal from another subscriber-side communication device.