Cisco Model 6944 and 6940 Node bdr Dig Rev 2 1 Mux System for Prisma II Installation Guide
Effects of Companding
Companding (a shortened form of the words “compress” and “expand”) is a
technique by which the dynamic range of a link may be increased. Consider a link of
the form shown in Figure A3.
technique by which the dynamic range of a link may be increased. Consider a link of
the form shown in Figure A3.
Input
Transfer
Characteristic
Output
Transfer
Characteristic
+
V
I
V
O
Noise
V
L
Figure A3. Link Block Diagram
V
I
represents the signal at the input to the link. V
L
represents the desired signal
inside the link. It is assumed that noise is added to the signal as it passes through
the link. V
the link. V
O
represents the signal plus noise at the output of the link.
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Improving the Performance and Capacity of Digital Reverse Systems
4000819 Rev B