Impact of Crosstalk Estimation on the Dynamic Spectrum Management Performance

The development and assessment of spectrum management methods for the copper access network are usually conducted under the assumption of accurate channel information. Acquiring such information implies, in practice, estimation of the crosstalk coupling functions between the twisted-pair lines in the access network. However, this estimation is not supported or required by current digital subscriber line (DSL) standards. In this work, we investigate the impact of non-ideal crosstalk estimation on the dynamic spectrum management (DSM) performance. Two different crosstalk estimators are considered: a conventional model-based estimator and a novel estimation procedure. The DSM performance is evaluated based on the obtained crosstalk estimates for two different network scenarios consisting of real twisted-pair cables. For a reference comparison, the crosstalk channels are measured with a network analyzer. The simulation results indicate that the novel estimation procedure achieves DSM performance results close to the ones obtained with the network analyzer and that the model-based estimator can lead to an inaccurate rate estimation.