a system and method for signal processing in a cable modem termination system is provided . a cmts receiver in communication with a plurality of cable modems at a upstream signal or a cable modem receiver in communication with the cmts at a downstream signal . a plurality of advanced time division multiple access channel processors include a filter for recovering an atdma signal and a orthogonal frequency division multiplexing channel processor includes a filter for processing a combined ofdm and atdma signal . a summation module subtracts the atdma signal from the combined atdma and ofdm signal to obtain a clean ofdm signal .