Adapted optimization criterion for FDM-based DMT-ADSL equalization

The ANSI T1E1.4 Committee finalized the standardization of the asymmetric digital subscriber loop system and the usage of discrete multitone modulation as the ADSL line coding scheme. In order to separate the upstream channel from the downstream channel, the committee accepted two approaches as vendor options: echo cancellation and frequency division multiplexing. We illustrate the impact of the FDM approach on the equalization problem. The unsatisfactory performance of formerly known algorithms is described. A new, simple and near-optimal equalization optimization criterion that is an FDM-based DMT-ADSL is proposed