Optical passive network system and its operation method

An optical communication system connecting a parent station and a plurality of child stations via an optical fiber network equipped with an optical splitter comprising a relay for relaying a signal for transmission/reception between the parent station and the plurality of child stations in said optical fiber network,

• said relay having a control unit including:
• a measuring unit for measuring a transmission distance or time to each child station;
• a determining unit for determining a timing for each of a plurality of groups dividing the plurality of child stations when the child station transmits a signal, in response to a transmission bandwidth request indicating a data amount waiting for transmission from the child station, and
• a signal processing unit for processing a signal received from the child station and transmitting the processed signal to the parent station, wherein:
• said relay notifies each child station of the timing determined by said determining unit after measurement by said measuring unit;
• upon reception of a burst signal constituted of a header and a payload from the child station at the notified timing, said signal processing unit deletes a portion of the header of the received burst signal in accordance with the timing, and converts the received burst signals into a series of signals by inserting a signal received from an arbitrary child station of each group after changing a timing into the deleted area and a gap area between received burst signals to be transmitted to the parent station;
• and
• the parent station receives the series of signals converted by said relay from signals transmitted from the plurality of child stations.

An operation method for an optical communication system connecting a parent station and a plurality of child stations via an optical fiber network equipped with an optical splitter includes a relay for relaying a signal for transmission/reception between the parent station and the plurality of child stations in said optical fiber network, wherein:

• when said optical communication starts operating, said relay measures a transmission distance or time between said relay and the plurality of child stations;
• in operation of said optical communication system, said relay determines a timing when each of the plurality of child stations transmits a signal, in response to a measurement result and a transmission bandwidth request indicating a data amount waiting for transmission from the plurality of child stations, and makes each of the plurality of child stations transmit a burst signal constituted of a header and a payload at the timing;
• said relay deletes a portion of the header of the burst signal received at the timing and converts the received burst signals into a series of signals by inserting a dummy signal into the deleted area and a gap area between received burst signals to be transmitted to the parent station;
• and
• the parent station receives the series of signals converted into signals transmitted from the plurality of child stations by said relay.

An operation method for an optical communication system connecting a parent station and a plurality of child stations via an optical fiber network equipped with an optical splitter includes a relay for relaying a signal for transmission/reception between the parent station and the plurality of child stations in said optical fiber network, wherein:

• when said optical communication starts operating, said relay measures a transmission distance or time between said relay and the plurality of child stations;
• in operation of said optical communication system, said relay determines a timing for each of a plurality of groups dividing the plurality of child stations when each of the plurality of child stations transmits a signal, in response to a measurement result and a transmission bandwidth request indicating a data amount waiting for transmission from the plurality of child stations, and makes each of the plurality of child stations transmit a burst signal constituted of a header and a payload at the timing;
• said relay deletes a portion of the header of the burst signal received at the timing and converts the received burst signals into a series of signals by inserting a signal received from an arbitrary child station of each group and subjected to a change in a timing into the deleted area and a gap area between received burst signals to be transmitted to the parent station;
• and
• the parent station receives the series of signals converted into signals transmitted from the plurality of child stations by said relay.