Analysis of Different Cloud-RAN Implementation Strategies in Small Cells Scenarios

The main objective of this work was to analyse different strategies for the implementation of Cloud Radio Access Networks (C-RAN) in an existing LTE-A network, by taking advantage of the functional split of a base station into Remote Radio Head and Baseband Unit, with the centralisation of the processing power in standard data centres. Four different strategies are compared: Minimise Delay, Load Balancing, Maximise Multiplexing Gain, and Minimise Number of Pools. The location of existing base station and possible data centres is taken as input. The metrics taken for the analysis are fronthaul latency, pool capacity of hourly traffic, processing power capacity, and multiplexing gain. The total cost of ownership model is also presented, to estimate possible cost savings. The model was implemented in a tool that enables the study of any scenario. The results obtained for the city of Oporto prove that a C-RAN implementation with 19 pools is possible without introducing latency problems; the operator can combine different traffic profiles, and achieve a multiplexing gain up to 1.31 that can be translated into capacity savings, and cost reductions of 63 % in capital investment and 31 % in operational expenditure can be achieved.