The enhanced performance of combined multicarrier and CDMA techniques in multipath fading channels

The enhanced performance of combined multicarrier and code division multiple-access techniques in multipath fading mobile communication channels is investigated in this paper. In particular, computer simulation is used for the comparison between three multiuser multicarrier CDMA modulation techniques, including OFDM, multicarrier code division multiple-access (MC-CDMA) and multicarrier-direct sequence (MC-DS-CDMA). The point of comparison, here, is the performance of these different schemes in the presence of a Rayleigh fading channel. Both slow and fast fading is considered in the simulations. It is required to investigate which system gives the best performance if different path channels with different values for the Doppler shift are taken into consideration. The paper also includes a detailed review of the three considered systems and their properties, advantages and limitations as well as a description of the fading channel model.