MCM systems with waveform shaping in multi-user environments: effects of fading, interference and timing errors

A unified procedure to characterize the effect of interchannel and intersymbol interference, Doppler and fading in multicarrier modulation (MCM) systems, is presented. The effect of different waveform shapes is considered in order to check the possibility of utilizing MCM as a multiple access technique. The degradation of system performance due to time and frequency offsets typical of multi-user environments is evaluated. In order to compare in a concise way different schemes, graphs showing time-frequency signatures, are introduced. The effect of the number of subcarriers and sampling frequency offsets in FFT-based implementation is also taken into account.