Systems and methods for a multicarrier modulation system with a variable margin

Abstract

A multicarrier modem has a plurality of carriers over which data is transmitted. By assigning, foe example, one or more different margins to the individual carriers the data rate and impairment immunity can be increased.

1 .- 45 . (canceled) 
     
     
         46 . A method for adjusting margins in a multicarrier modem communicating over a plurality of subchannels comprising:
 assigning a first margin to one or more subchannels in the modem resulting in a first data rate;   assigning a second margin to the one or more subchannels in the modem resulting in a second date rate,   wherein:
 the second margin is higher than the first margin, 
 the second data rate is lower than the first data rate, 
 the assigning of the second margin is based on at least an increase in a bit error rate on the one or more subchannels, and 
 the increase in the bit error rate occurs after digital subscriber line service is already initiated.