Modified Coordinated Multipoint Transmission in Ultradense Networks

Ultradense network (UDN) is considered as one of the key technologies in the future 5G network. The system capacity could be increased greatly with the cell densification. It can be realized by the deployment of small cells which have low transmit power and coverage. However, the densification of small cells can also bring strong inter-cell interference (ICI) which limits the system performance. Coordinated multipoint transmission (CoMP) can eliminate interference or transform the interference into useful signals. It is introduced to improve the cell edge users’ performance in the traditional sparse network, while it has some constraints in the dense network. In this paper, we propose a modified CoMP which can improve the performance of ultradense network. Users choose multiple small cells according to two different thresholds, and the small cells serve the users by transmitting signals or just mute. The simulation results show that this method can improve the system energy efficiency with little data rate reduction.