Introduction - Meridian Nortel 1 Option 11C Technical Reference Manual

Page 158 of 544

Introduction

553-3011-100 Standard 14.00
Transmission parameters
Absolute group delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Group delay distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Longitudinal balance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Crosstalk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
The Meridian 1 Option 11C system accommodates two companding laws to
convert signals from analog to digital and from digital to analog:
• µ-Law which is used in North America and Japan.
• A-Law which is used in most other areas of the world, including Europe.
The following transmission specification applies to both standard µ-Law and
A-Law cards. There are other countries which have their own transmission
plans and thus use unique cards which have had adjustments made to
accommodate their transmission specifications. These adjustments were
generally in A/D and D/A gains.
The transmission characteristics are given in the following section. Except
where indicated otherwise, the design objectives given are met when
measured between 2 wire and 4 wire analog input and output interfaces
terminated with their nominal impedance.
The reference frequency for µ-Law is 1024 Hz and A-Law is 820 Hz.
The reference level is -10 dBmO (as an alternative a reference level of
0 dBmO may be used).
January 2002
IMPORTANT