Radio over fiber (RoF) technology is one of the emerging options to improve the cost and efficiency of fronthaul connections for virtualized RANs (see lead article), and is expected to play a greatly enhanced role in 5G. A European Union-backed project says it has proved the feasibility of an RoF solution in the 60 GHz unlicensed millimeter wave band, which could open new horizons for fronthaul, backhaul and converged wireless/wireline access. In RoF systems, light is modulated by an RF signal and transmitted over an optical fiber link, resulting in high performance and reliability. In cellular networks, it can be used to transport signals between a central baseband and the remote radio/antenna units, in a vRAN or base station hotel…