Experimental evaluation of fourth generation DSL in different DSM scenarios

Recently, the industry and the academy started to discuss the development of the fourth generation DSL systems. For example, within this context, ITU started working in G. fast DSL standard. A trend in this new generation is to increase the end-user bit rates by extending the frequency rage of transmission signals and reducing the copper loop length. For the frequency range being considered for use in G. fast for example, crosstalk is an even worse impairment than it is for current DSL deployments. Hence, it is sensible to study dynamic spectrum management (DSM) techniques to overcome the crosstalk effects. This work presents an experimental evaluation in order to verify the behavior of fourth generation DSL systems when different levels of DSM techniques are used, highlighting the coexistence of vectored, DSM level 3, and non-vectored sub-systems. The results were obtained based on short copper cable measurements and power spectrum density simulations.