Wireline Communications

Today’s growing use of multimedia applications over the internet demands ever increasing data rates. With the expansion of fiber networks only the last meters from the distribution point (DP) to the customer premises equipment (CPE) have to be bridged by existing copper wires. Recently, the standard for these fiber-to-the-distribution-point (FTTdp) DSL deployments, called G.fast, has been finished.

The target is to increase the data rate over the short copper link up to 1 Gbit/s, which is an increase by the factor of ten compared to VDSL2, by extending the frequency band from 30 Mhz up to 212 MHz. At higher frequencies, the crosstalk between the lines is amplified, which makes crosstalk management essential to obtain the targeted data rates.

At our institute, we investigate novel linear and nonlinear precoding techniques suited for the new channel conditions arising in G.fast systems. Furthermore, we consider different optimization criteria other than sum rate, to adapt the resource allocation to the users individual needs, shifting precoder design from a operator to a user focused view.