Inter-Cluster Design of Wireless Fronthaul and Access Links for the Downlink of C-RAN

This letter studies the joint design of wireless fronthaul and radio access links for the downlink of a cloud radio access network (C-RAN). In a C-RAN, high spectral efficiency can be achieved by migrating the baseband processing functionalities to a baseband processing unit (BBU). However, due to the increased system cost, the size of cluster should be kept relatively small, and hence the spectral efficiency performance tends to be limited by the impact of inter-cluster interference signals. This letter tackles the problem of jointly optimizing the fronthaul and access links across multiple clusters with the goal of maximizing the sum-rate of all the user equipments belonging to the clusters while satisfying the power constraints at the BBUs and remote radio heads. Via numerical results, the effectiveness of the proposed algorithm is confirmed.