Network Availability of Hybrid FSO/mmW 5G Fronthaul Network in C-RAN Architecture

New innovation approach called -centralized radio access network(Cloud-RAN or C-RAN) - architecture is developed to meet theexplosive growth in mobile traffic in the 5th generation (5G) mobilenetworks especially in the need of high-speed, high capacity, realtimedata, and high-reliability. In C-RAN architecture, fronthaulnetworks connect between the radio units called -Remote RadioHeads (RRHs)- and the processing unit called -Base BandProcessing Unit (BBU)-. Recently, hybrid free space optics (FSO)and millimeter waves (mmW) network is considered to be apromising solution that can match with the requirements of 5Gfronthaul networks. In this paper, hybrid FSO/mmW links at eachRRH is proposed to enhance the performance of C-RAN fronthaulnetwork at various weather conditions. The performance of hybridFSO/mmW technology as a fronthaul network is evaluated atdifferent weather conditions and compared to other technologies.The numerical results reveal that improvements are obtained innetwork reliability using hybrid FSO/mmW fronthaul network,especially at severe weather conditions.