Wireless Fronthaul Allocation for Downlink Coordinated Transmission in Cloud Radio Access Network

Cloud radio access network (C-RAN) is a promising architecture to meet the future demands of cell densification and explosive traffic volume. One key enabling factor of C-RAN is the availability of fronthaul link, over which the information between remote antennas and centralized processors is readily exchanged. This paper considers wireless fronthauled C-RAN, and proposes to enhance sum-rate performance under coordinated transmission by flexibly allocating wireless fronthaul bandwidth among antennas. For each antenna, we introduce degree of contribution to quantify its coordination gain, and compute its occupied fronthaul bandwidth as the cost. With the gain and cost, we formulate the wireless fronthaul allocation as a knapsack problem, which is then solved by proposed virtual antenna method and recursive divide and conquer algorithm. Simulation results verify the effectiveness of the proposed scheme in wireless fronthauled C-RAN.