Experimental performance evaluations of CoMP and CA in centralized radio access networks

According to International Mobile Telecommunication’s requirements for 2020, next generation cellular networks such as 5G need to meet certain Key Performance Indicator targets. Centralized-Radio Access Networks (C-RAN) is a novel technique that can address growing capacity needs of Mobile Network Operators (MNOs) due to ever increasing demands of their users. In order to meet stringent requirements of next generation cellular networks, C-RAN enabled techniques have attracted a lot attention due to their efficient spectrum (band, bandwidth) utilization [e.g. via carrier aggregation (CA)], spectrum efficiency (e.g. via Inter-Cell Interference Co-ordination and cancellation using Coordinated MultiPoint (CoMP) Transmission/Reception). In this paper, we investigate three different CA scenarios along with their benefits and limitations from the perspective of MNO. Additionally, we analyze inter-Baseband Unit (BBU) uplink (UL) CoMP feature as a real-world experimental C-RAN implementation in an operational suburban site of Istanbul in Turkey. Quantitative CA performance measurements demonstrate performance comparison of the considered three CA scenarios, and depending on each MNO’s strategy, different CA gains are observed (e.g. LTE 1800 Mhz MNOs can benefit more from L800 umbrella coverage scenario). Our coordinated inter-BBU UL CoMP results indicate that around \(7\%\), \(9\%\) and \(6\%\) gains can be achieved in UL cell, user and cell-edge user throughput respectively.