| 摘要 |
PROBLEM TO BE SOLVED: To add an order wire function that conducts communication for system maintenance, without causing deteriorating transmission efficiency in a passive double star(PDS) configuration contained in an optical subscriber line terminator to deteriorate. SOLUTION: In this optical subscriber system, an optical subscriber line terminator 20 installed at a station side contains a plurality of optical subscriber units 1, 2,..., n that are configured in a passive double star(PDS) configuration, and the system adopts the time division multiplex(TDMA) system for downstream paths and the time division multiple access (TDMA) system for upstream paths for transmitting signals. In this case, a burst signal (order wire signal) for a maintenance telephone signal (order wire) is set to a delay measurement area in a transmission frame. |
