Effect of overlapping between successive carriers of multicarrier CDMA on the performance in a multipath fading channel

The effect of the overlapping between successive carriers of a multicarrier code-division multiple-access system on the performance in a multipath fading channel is investigated. Transmitted data bits are serial to parallel converted to a number of parallel branches. On each branch each bit is direct-sequence spread-spectrum modulated and transmitted with certain number of carriers. The separation between successive carriers is allowed to vary to achieve various overlapping percentages. The system is analyzed with a conventional matched filter receiver. It is shown that for each number of carriers there exists an optimum overlapping percentage at which the performance of the system is optimized. The results show that a considerable improvement can be achieved.