Optical Wavelength Conversion Unit. STM-64 Transmitting Optical Wavelength Conversion Unit with FEC Function, страница 33

n  This situation might happen due to two reasons: (i)both active and standby fibers are damaged; (ii)the fiber at the transmitting end is broken before the 3dB coupler performs splitting. When these two conditions happen, OLP board of this site will not generate protection switch, while it only reports RLOS alarm of active/standby fibers.

n  Pw ≤-35dBm, Pp>-34dBm

n  This condition results from the fact that the active fiber is damaged while the standby fiber is normal. Under this condition, OLP board of this site will generate protection switch from the active fiber to the standby fiber, ( if services are already working on the standby fiber, no switch will occur) and report RLOS alarm of the active fiber and protection switch event.

n  Pw>-34dBm, Pp ≤-35dBm

This condition results from the fact that the standby fiber is damaged while the active fiber is normal. Under this condition, OLP board of this site will generate protection switch from the standby fiber to the active fiber, (if services are already working on the active fiber, no switch will occur), and report RLOS alarm of the standby fiber and protection switch event.

n  Pw>-35dBm, Pp>-35dBm

This condition can be discussed in the following three cases:

(i) |Pw-Pp|≥ 5dB

It means that signal deterioration (SD) occurs in the fiber with smaller optical power. If at this time the services are working in this fiber, the services will be switched to the fiber with larger optical power, ( if the services are already working in the fiber with larger optical power, no switch will occur), and corresponding alarm and protection switch event will be reported.

(ii) 3dB≤|Pw-Pp|<5dB

It means that the power attenuation of the active and standby fibers is not consistent but not so serious as up to the thresholds of SD. No switch occurs, but only corresponding alarm is reported.

(iii) |Pw-Pp|<3dB

It means that both active and standby fibers are in normal status, and do not need to be processed.

3. Application

n  Optical ports "SO1" and "SO2" of OLP board transmit optical signals of this site to the two lines of active/standby fibers. "RI1" and "RI2" receives optical signals sent to this site from the two lines of active/standby fibers., "S" is connected to "TO" of SCA board and "R" to "RI" of SCA board.

n  OLP board can be inserted in 1~13 board position of OptiX BWS 320G subrack.

n  The optical connector on OLP board handle bar is of SC type.

4. Alarms and performances

Since OLP board mainly receives the multi-channel signals sent from the optical fiber trunk, its alarms are mainly in the aspect of optical detection, as shown in Table 3-22.

Table 3-22 List of OLP board alarms