Towards Dynamic 5G Networks Utilizing Flexible Function Split

The migration of wireless mobile networks from the relatively limited microwave radio spectrum to the "all-spectrum" principle of communication, which aims to make use of microwave and millimeter wave mobile networks as well as fixed point sub-terahertz and visible light communications, has predetermined the need for new network paradigm. Therefore, designing an efficient network along with specialized protection system that encompasses the densely distributed remote radio units (RRUs) as well as fronthaul fiber links and their RF interfaces becomes increasingly important and complex. In this paper, we first analyze the function split concept in the design of fronthaul schemes, mindful of the required fronthaul bandwidth and RRU complexity. We then experimentally demonstrate a mobile-fronthaul protection algorithm that supports proactive, low complexity self-healing by making use of low complexity RRUs while imposing minimum changes on fronthaul performance. The proposed scheme exploits RF domain switching to support seamless 5G-grade service restoration in less than 2 microseconds without causing any service disruption to connected users.