DCT-based multicarrier schemes for doubly-selective channels

We compare four different multicarrier schemes in a discrete-time, oversampled domain over doubly-selective channels. We find that all the schemes can be implemented in a reduced complexity way, resorting to suitable fast transforms like DFT, DCT, or DST. For all models we assume either a rectangular base pulse or a properly designed prototype pulse, well localized in both time and frequency domains, and we show that such a technique can be applied to our discrete-time block-based model. We highlight the similarities and the differences between some recently proposed multicarrier modulations based on DCT and DST to mathematical concepts such as the Wilson base, that in turn will be used to develop a novel and effective multicarrier format, ready to be employed in practical communication systems. All analyzed modulations will be compared in terms of spectral efficiency and BER performance in practical implementations.