Spectrally compatible mask for enhanced upstream data rates in DSL systems

Abstract

A method and apparatus for providing extended upstream data transmission in a band having a lowest frequency f0 by an end user terminal unit in an asymmetric digital subscriber line communication between a central office terminal unit and the end user terminal unit, using a loop having a length. In the method, a target rate of upstream data transmission is provided. A plurality of sets of values are determined, of (1) an extension frequency f2 that is higher than a frequency f1 for upstream data transmission, f1 being a frequency established for non-extended upstream data transmission, the region bounded by f1 and f2 being an extension band for upstream data transmission, and (2) a maximum power level S2 for the extension band determined by the extension frequency in the set. Using both terminal units, a selection set of values is selected by performing a signal-to-noise ratio determination for each of the sets of values and determining the set of values that results in an upstream data rate that approximates the target rate. Data is transmitted upstream by the end user terminal unit using the selection set of values.

Dependencies are inferred from the claim text.