363-206-305
Technical Specifications
Issue 3 June 2000
10-37
Table 10-18 details the maximum link budgets for each pairing of OC-3 rate OLIUs
when operating on single-mode (SM) fiber. These numbers give the maximum
attenuation acceptable for proper operation of each transmitter/receiver pair. The
link must have no more than this much attenuation either from fiber loss, splice
loss, connector loss, external attenuators or a combination of these or the link will
not operate properly. The maximum link budgets for SM fiber were calculated
using the following margins:
â–
Optical Path Penalty (dB) 1.0
â–
Connector Loss (dB) 1.5
Table 10-18. OC-3 Rate OLIU Mixes - Maximum Link Budgets for SM Fiber
(dB)
NOTE:
The maximum link budget is not always symmetrical. A transmitter/receiver
pair may have one maximum link budget in one direction and another in the
opposite direction. For example, a 28G-U OLIU transmitting to a 22F OLIU
has a maximum SM link budget of 25.0 dB. In the opposite direction,
though, a 22F OLIU transmitting to a 28G-U OLIU has a maximum SM link
budget of 15.0 dB. Be careful of this asymmetry when planning and
engineering a link having mixed OLIUs. Note also that the 22D-U OLIUs will
not operate when transmitting into single-mode fiber.
Transmitter
Receiver
22F/
22F-U/
22F2-U
22G-U/
22G2-U/
22G3-U /
22G4-U
28G-U/
28G2-U
22F
22G-U/22G2-U
22G3-U/22G4-U
28G-Type
15.0
23.0
25.0
25.0
15.0
23.0
25.0
25.0
15.0
23.0
25.0
25.0