Downlink partial spectrum sharing scheme in cognitive LTE-A heterogeneous networks

In order to handle the cross-tier interference problem and improve the throughput of a long-term evolution advanced (LTE-A) heterogeneous network, we propose a downlink partial spectrum sharing scheme using cognitive radio (CR) technique. In this paper, radio resources are divided into three parts: macro-dedicated portion, shared portion and femto-dedicated portion. Moreover, we propose a mixed sharing scheme to share the resources in the shared portion to meet the CR based spectrum sharing requirement of interweave paradigm. Simulation result shows the proposed scheme can get the best performance in terms of the throughput. Also we can see the trend that the total throughput is increased with the increasing of FDP Ratio when the cross-tier fair factor is decreased which reflect the resources competition relationship between the macrocell and the femtocells.