Cisco Model 6944 and 6940 Node bdr Dig Rev 2 1 Mux System for Prisma II Installation Guide

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Resulting NPR 
The quantization noise in a companded system changes as a function of signal level.  
This change has an impact on the NPR curve.  A typical NPR curve for the 4:1 bdr 
system is shown in Figure A7. 
 
bdr-c 4:1 DM 5 to 40 MHz NPR @ 25C
20
25
30
35
40
45
-85.0
-80.0
-75.0
-70.0
-65.0
-60.0
-55.0
-50.0
-45.0
Input Power (dBmV/Hz)
NPR (dB)
 
 
Figure A7.  NPR for 4:1 bdr 
 
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4000819 Rev B 
Improving the Performance and Capacity of Digital Reverse Systems 
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