Presents a simulation-based study evaluating the performance oftrellis-coded modulation with combined code/ISI (intersymbolinterference) sequence estimation for high-bit-rate (800-kb/s)transmission on subscriber loops. The receiver contains the fractionallyspaced forward filter of a decision feedback equalizer as a front end;this is shown to suppress phase-synchronized crosstalk very effectively.It is observed that trellis codes with large numbers of states areneeded to obtain reasonable coding gain on a channel with severe ISI,such as a DSL (digital subscriber loop). Coded modulation along with areduced-complexity sequence estimator (combined equalization anddecoding with fewer states) can improve the transmission range of thehigh-bit-rate DSL system. The results indicate that achievinghigh-bit-rate transmission on the worst case CSA (carrier serving area)loops with 12-dB noise margin under stationary interference conditionsis not possible, while loops longer than the CSA limit can be coveredunder cyclostationary interference
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