TERMINAL DEVICE, CENTER DEVICE, OPTICAL COMMUNICATION NETWORK SYSTEM, AND UPLINK SIGNAL TIMING CONTROL METHOD

摘要

PROBLEM TO BE SOLVED: To independently set bit rates of an uplink signal and a downlink signal in PON and thereby facilitate processing for establishment of synchronization and attain low cost.

SOLUTION: The uplink signal timing control method of the present invention is applicable to PON. The method is to control the timing of an uplink optical signal from the terminal device to a center device at an ideal timing. The center device transmits optical clock pulses in synchronism with the ideal timing to the terminal device and the terminal device subjects the incoming optical clock pulses to delay control and transmits them in return. The center device detects a timing shift between the ideal timing and the returned optical clock pulses, and reflects digital data at least containing timing shift information on waveforms of outgoing optical clock pulses. The terminal device performs delay control to the optical clock pulses received in response to the incoming digital data. The center device assumes completion of timing control when the timing shift is less than a threshold.

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