| 摘要 |
<p>The purpose of the present invention is to provide: a subscriber-side device that is capable of generating accurate time information, even when the portion that receives a downlink signal is powered off, and is capable of synchronization with other devices; and an optical transmission system equipped with same. This subscriber-side device uses a time correction value generated on the basis of the frequency deviation between a synchronous clock signal and a free-running clock signal to correct free-running time information generated on the basis of the free-running clock signal and output the results. When in a loss-of-signal state in which the subscriber-side device cannot recognize or receive a downlink signal from a station-side device, the free-running time information is corrected using the time correction value generated prior to the occurrence of the loss-of-signal state, and is output.</p> |
