DSL Crosstalk Simulation and Calibration

The performance of DSL transceivers can be impaired by interference from other transceivers operating over wires in the same binder group. It is therefore important to test DSL transceivers in the presence of crosstalk, which can be simulated in a programming environment such as MATLAB. The simulated crosstalk can then be exported to an arbitrary waveform generator (AWG) for injection onto the line through a high-impedance noise injection circuit. This document describes a method of crosstalk simulation and calibration whereby white gaussian noise (WGN) is passed through a frequency-domain filter that gives the noise the spectral characteristics of crosstalk. The crosstalk is calibrated by measuring its power with a vector signal analyzer (VSA) and adjusting the output level on the AWG to achieve the desired noise power. By using MATLAB to estimate the simulated crosstalk power in the same manner as the VSA, the calibration can be performed in MATLAB without taking actual measurements.

Test Service: 
DSL Testing Services
Authors: 
Tim Clark (UNH-IOL)
Category: 
White Papers
Published In: 
05/11/2004