Efficient channel shortening in communication systems

A communication system includes a channel shortening filter to reduce intersymbol interference and facilitate recovery of communications. The channel shortening filter preferably includes a energy concentration filter that optimizes SNR or SINR or other performance criterion and a impulse response tail canceller filter that eliminates energy or, equivalently, cancels coefficients outside the allowed delay-spread window for the channel. Preferably the filters are calculated using signal decomposition.