Cisco 1310 nm, 1550 nm, and CWDM Analog Rev TXs for Model 6940 6944 GM Node 数据表

 

9

 
 

 

Link Loss (dB) 

Model 6940/42/44 & GainMaker DFB TX 

(Std and High Gain) 

1 +2 
2 +2 
3 +2 
4 +1.5 
5 +1 
6 +1 
7 0 
8 -1 
9 -2 

10 -3 
11 -4.5 
12 -6 
13 -7 
14 -9 
15 -11 
16 -12 
17 -14 
18 -16 
19 -18 
20 -20 

 
Using the NPR Link Loss Correction Factor (applies to Model 6940, 6944, and GainMaker analog TXs only) 
 
The NPR performance plots contained in this document depict the NPR performance on a reference 7 dB fiber 
optic link. 
 
With other link losses, both the: 
 

•  NPR dynamic range for a given minimum NPR (C/N) performance 

•  NPR value for a given transmitter RF input level 

 
will vary from that shown on the reference 7 dB link plots. 
 
To determine an NPR dynamic range for a different link loss, add (or subtract) the correction factor associated 
with the desired link loss to (or from) the dynamic range shown on the reference 7 dB link NPR plot.  Note that the 
associated increase (or decrease) in dynamic range affects only the left side of the NPR curve (minimum RF input 
side) since that is the portion of the curve affected by changes to the traditional noise sources associated with the 
optical link. 
 
To determine an NPR value for a different link loss, add (or subtract) the correction factor associated with the 
desired link loss to (or from) the NPR value shown on the 7 dB link NPR plot for a given RF input level.  Again, only 
the NPR values on the left side of the NPR curve (pre-peak values) are to be adjusted.  The NPR values and slope 
associated with the right side of the NPR curve (post peak values) are primarily due to laser clipping at high RF 
input levels, and therefore do not vary appreciably with link loss.