With the exponential growth in traffic demands during past years, Heterogeneous Networks (HetNets) are envisioned as the major capacity and performance enhancement enablers by means of increasing the spectral efficiency per unit area. Several multi-cell cooperation techniques have been developed in order to improve the performance of HetNets, such as Range Extension (RE) and enhanced Inter-Cell Interference Coordination (eICIC) for co-channel deployments and inter-site carrier aggregation (CA) for dedicated deployments.
The main objective of this study is to analyze the performance of different multi-cell cooperation techniques in a site-specific scenario (central London area) as compared to the case without multi-cell cooperation. The performance of these multi-cell cooperation techniques has been well studied in 3GPP scenarios. But in the site-specific scenario, both the traffic distribution and network layout are far more irregular than in 3GPP scenarios, which calls for a deeper study considering local characteristics.
For co-channel deployment, dynamic algorithms used for cell selection and interference management are proposed in order to adaptively adjust the configurations (RE + eICIC) according to the local characteristics (such as the load and interference conditions). The results show that the performance with dynamic algorithms is much better than with static algorithms, achieving an overall user throughput gain up to 120% and 47% over the static configuration for the 5th and 50th percentile respectively.
For dedicated carrier deployment, inter-site CA proves to have good performance in the site-specific scenario, providing an overall user throughput gain up to 100% and 28% for the 5th and 50th percentile respectively, compared to the case without CA. The gain of inter-site CA depends on the UE’s channel quality to both layers (macro layer and small cell layer) and the density of the eNBs of the site-specific scenario.