363-206-295
Technical Specifications
Issue 1 December 1997 10-7
Long Reach OC-3 Interface (21G/21G-U/
21G2-U OLIU) 10
■ Optical Specification
The 21G/21G-U/21G2-U OLIU photonics meet or exceed SONET
specifications (TR 253, Iss. 2 - LR-1 MLM category). The multilongitudinal
laser transmitter supplies an non return to zero (NRZ) coded signal. The
PINFET receiver allows direct optical loopback without the use of an
external attenuator, when the TRANSMIT POWER switch is on the low
setting.
The 21G/21G-U/21G2-U long reach OC-3 interface supports span lengths
up to 55 km, assuming 0.45 dB/km single-mode fiber (including splices)
and the span engineering rules outlined in Figure 10-1. Transmit and
receive powers are referenced to points S and R as shown in Figure 10-1.
Table 10-5 and Table 10-6 provide detailed specifications and link budget
information for the 21G/21G-U/21G2-U OLIU.
Figure 10-1. Optical System Interfaces (Points S and R)
■ Alarm Thresholding
The following parameters are monitored at the OC-3 interface.
— LOS
— LOF
— LOP
OLIU
Point S
Transmitter
(Tx)
Transmitter/Connector
Assembly
Station Cable
Fiber
Crossconnect
Fiber
Crossconnect
Outside Plant Cable
Connections
OLIU
(Rx)
Assembly
Station Cable
Receiver
Receiver/Connector
Point R
To Next Page
Loading...
Need help?
General
