Load balancing by dynamic BBU-RRH mapping in a self-optimised Cloud Radio Access Network

In this paper, a load-balancing scheme is investigated for C-RAN to optimise its performance subject to physical resource limitation and users Quality of Service (QoS) demands constraints. The Remote Radio Heads (RRHs) are allocated to the Base Band Units (BBUs) dynamically for load balancing and efficient resource utilisation. Dynamic BBU-RRH mapping is formulated as a linear integer-based constrained optimisation problem. An Estimation Distribution Discrete Particle Swarm Optimisation (EDDPSO) algorithm is developed for optimisation and to achieve a balanced network. Computational results based on two benchmark problems demonstrate that EDDPSO delivers optimum performance for small-scale networks. However, a close-optimum is achieved for large-scale networks which is 99.06% of the optimum value. The EDDPSO algorithm is fast and less complex compared to Exhaustive Search (ES) algorithm.