Lucent Technologies FiberReach DDM-2000 - Page 492

363-206-305
Technical Specifications
10-18
Issue 3 June 2000
Long Reach OC-3 Interface (22G-U/22G2-U/
22G3-U/22G4-U OLIU)
10
■
Optical Specification
The multilongitudinal mode (MLM
*
) laser transmitter supplies an NRZ-
coded signal. For direct optical loopbacks, at least 7.0 dB (use 10 dB
attenuator, see Table 10-21) of attenuation is needed for the 22G-U. No
attenuation is needed for the 22G2-U/22G3-U/22G4-U.
The 22G-U/22G2-U OLIU long reach OC-3 interface supports span lengths
up to 51 km, assuming 0.45 dB/km single-mode fiber and the span
engineering rules outlined in Table 10-7. Transmit and receive powers are
referenced to Points S and R (Figure 10-2). Table 10-6, Table 10-7, and
Table 10-8 provide detailed specifications and link budget information for
the 22G-U/22G2-U OLIU.
The 22G3-U/22G4-U OLIU is a SONET compliant long reach OC-3
interface supporting span lengths up to 55 km, assuming 0.45 dB/km
single-mode fiber and the span engineering rules outlined in Table 10-7.
Transmit and receive powers are referenced to Points S and R
(Figure 10-2). Table 10-6, Table 10-7, and Table 10-8 provide detailed
specifications and link budget information for the 22G3-U/22G4-U OLIU.
■
Alarm Thresholding
The following parameters are monitored at the OC-3 interface.
— Loss of signal (LOS)
— Loss of frame (LOF)
— Loss of pointer (LOP)
— Line AIS
— B2 thresholding signal fail
— B2 thresholding signal degrade. (B2 signal degrade thresholds are
user settable in the range from 10
-5
to 10
-9
BER.)
■
Line PM (See Table 10-3 and Table 10-23.)
— Section SEFS
— Line parameter B2
— STS pointer justifications (OC-3 R11.0 and later)
— STS-1 Path PM. (See Table 10-3 and Table 10-23.)
* A higher quality SLM laser may be used instead of an MLM laser.