| 摘要 |
<p>PURPOSE:To detect a fault generated in the line of a host device from a device located at the low order by means of a bi-directional device in a bi-directional multiple system. CONSTITUTION:This system is provided with an R-side AIS detection part 12, an R-side synchronization detection part 13, S-side SINDWN (transmission input signal disconnection) detection parts 15 and 16, R OUT-side AIS insertion parts 17 and 18 on the R side, and an R-side SEND detection part 19. The AIS alarm is sent to all the bi-directional low-order devices where a fault is generated. Thus, it can be notified to all maintenance persons of the device of the upper and lower lines (S and R directions) incapable of line service.</p> |
