Patent ID: 7564932

Claim:
A method for enhancing bit rates in a discrete multi-tone quad spectrum system, comprising: shaping in the time domain, a power spectral density PSD mask associated with a signal; implementing a transmit filter that operates at a certain frequency, with one or more notched areas at specific frequencies for a short loop transmit filter characterized by a shallow notch utilized for transmissions over short loops to facilitate smoother time domain equalization for resource-limited equalizers; implementing a second transmit filter for a long loop with one or more notched areas, wherein the short loop and the long loop are defined based on a predetermined threshold, and wherein the one or more notched areas for the short loop transmit filter have less depth than the one or more notched areas for the long loop transmit filter; determining bins associated with the notched areas; and determining the amount of attenuation of the signal power required to overcome the notched areas in the PSD mask.