Dedicated carrier deployment in heterogeneous networks with inter-site carrier aggregation

Heterogeneous networks (HetNets) have been extensively discussed in 3GPP to further enhance the system throughput of traditional well-planned macrocell deployment. In this paper, we consider a HetNet scenario consisting of macro eNBs and low-power nodes implemented as remote radio heads (RRHs) or picos with dedicated carrier deployment. Collaborative inter-site carrier aggregation (CA) is proposed in scenarios with macro+RRH deployment to make an efficient use of the fragmented spectrum from multiple cells. While in scenarios with macro+pico deployment, UEs can only connect to either the macrocell or the picocell using simple cell range expansion (RE). Extensive system-level simulations have been conducted to investigate the performance gains that can be achieved with intersite CA under different traffic models and user distributions. Results show that using inter-site CA between the macrocell and the small cell obviously offers higher throughput due to larger bandwidth accessibility for the terminals, especially in low load.