Frequency-domain extended models for equalization of doubly-selective channels

We consider frequency-domain equalization of single-carrier systems in doubly-selective channels. In this framework, we investigate the role of channel extension in the time domain on the performance of extended frequency-domain equalization. Specifically, we propose a new low-complexity channel extension technique, whose comparison with other techniques is performed by evaluating the approximation error of the channel matrix and the BER of banded linear MMSE equalizers.