Speed-aware multicarrier transmission and resource allocation scheme for the uplink channel of highly mobile networks

We propose a new transmission and resource allocation technique based on multicarrier direct-sequence CDMA (MC-DS-CDMA). The proposed system allocates subcarriers and spreading codes to users by considering their current bandwidth requirements and frequency shifts caused by their movement. Through the use of low-correlation spreading codes in close subcarriers, the scheme reduces the intercarrier interference generated by high-speed users while keeping the intersymbol interference at a low level due to multicarrier transmission. The analysis and results show that a substantial mitigation of both the intercarrier interference and bit error rate, without reducing the system bandwidth efficiency, can be achieved.