Abstract: A combined interference cancellation communication system employing forward error code (FEC) decoding for high spectral efficiency satellite communications. The disclosed system enables efficient utilization of available bandwidth through overlapping adjacent channels. A receiver is used to receive a waveform having data information and noise information. A filter bank is coupled with the receiver to receive and filter waveform and output channel information received by the receiver. The channel information received includes a combination of data signals and adjacent channel interference signals. A demodulator is provided to provide an estimation signal representative of an estimation of at least one parameter of the channel information. Soft-input and soft-output decoders are provided to receive the channel information in order to calculate and estimate interference values based on the estimation signal.