Patent ID: 8995837
Filing Date: 2015-03-31
Classification: H04B,H04J,H04L,H04Q,Y02D

Abstract:
1. A subscriber-side optical communication device that includes an optical transmission-and-reception module for performing transmission and reception of a signal with a station-side optical communication device and is configured to cause a receiver and a transmitter constituting the optical transmission-and-reception module to enter into a power-saving state separately, the subscriber-side optical communication device comprising: a clock regeneration unit that regenerates a clock based on a signal from the station-side optical communication device received by the optical transmission-and-reception module and supplies the clock; an internal clock source that generates an internal clock and supplies the internal clock; a time management unit that manages a time of the subscriber-side optical communication device based on the clock in a period in which the clock regeneration unit supplies the clock and manages the time of the subscriber-side optical communication device based on the internal clock in a period in which the clock regeneration unit does not supply the clock; a sleep-time control unit that decides, when a power-saving mode for causing the receiver to enter into a power-saving state for a predetermined sleep time is set, a receiver-time synchronization time that is a period in which the receiver is normally operated within the sleep time, based on a difference between predetermined information indicating a time in the station-side optical communication device included in the signal transmitted from the station-side optical communication device and the time managed by the time management unit; and a power-saving control unit that controls the receiver to be normally operated in the receiver-time synchronization time during the sleep time.