Worst-Case Power Budget And Penalties; Table B-7. 1000Base-Lx Receive Characteristics; Table B-8. Worst-Case 1000Base-Lx Power Budget And Penalties - Nortel BayStack 450-24T Using Manual

Using the BayStack 450 10/100/1000 Series Switch
Table B-7. 1000BASE-LX Receive Characteristics
Description
Receive sensitivity
Return loss (minimum)
Stressed receive sensitivity *, †
Receive electrical 3 dB upper cutoff frequency (maximum)
Vertical eye-closure penalty ‡
* Measured with conformance test signal at TP3 (see IEEE 802.3, Clause 38.6.11) for BER = 10
† Measured with a transmit signal having a 9 dB extinction ratio. If another extinction ratio is used, the stressed receive
sensitivity should be corrected for the extinction ratio penalty.
‡ Vertical eye-closure penalty is a test condition for measuring stressed receive sensitivity. It is not a required
characteristic of the receiver.

Worst-Case Power Budget and Penalties

Table B-8 lists the worst-case power budget and penalties for the 1000BASE-LX
models:
Note: The link power penalties (Table B-8) are used for link power budget
calculations only. They are not requirements and are not meant to be tested.
Table B-8. Worst-Case 1000BASE-LX Power Budget and Penalties
Parameter
Modal bandwidth as measured at
1300 nm (minimum, overfilled launch)
Link power budget
Operating distance
Channel insertion loss
Link power penalties
Unallocated margin in link power budget
B-6
(continued)
Value
– 19
12
– 14.4
1500
2.60
62.5 um MMF 50 um MMF
500 400
7.5 7.5
550 550
2.35 2.35
3.48 5.08
1.67 0.07
Units
dBm
dB
dBm
MHz
dB
at the eye center.
–12
10 um SMF
500 N/A
7.5 8.0
550 5000
2.35 4.57
3.96 3.27
1.19 0.16
309978-D Rev 01
Unit
MHz · km
dB
m
dB
dB
dB