5G/6G optical fronthaul modeling: cost and energy consumption assessment

Abstract

In fifth generatin (5G) and the future beyond 5G (6G) radio access networks (RANs), the cost of fronthaul deployment is a main challenge for mobile network operators. Depending on different constraints, there are various solutions to deploy an efficient fronthaul. Fiber-optic-based fronthaul offers long-term support with regard to a rapid increase in capacity demands. When fiber connections, either point-to-point (P2P) or point-to-multipoint [i.e., passive optical networks (PONs)], are not available due to economic or geographical constraints, new optical fronthaul solutions such as free space optics (FSO) can be applied. Before deploying any optical fronthaul architecture, mobile operators must assess its impact on the total cost of ownership (TCO) of the network (i.e., capital and operational expenditures). To assist operators in choosing the most cost-effective fronthaul architecture, in this paper, we show how to evaluate the TCO of 5G and beyond RANs while taking various fronthaul architectures (P2P, PON, and hybrid PON-FSO) into consideration. Furthermore, this paper answers the question of how much energy is needed to run a network using each of the considered optical fronthaul architectures. To do so, we propose a holistic framework based on an integer linear program that minimizes the TCO of the network. Furthermore, we propose a heuristic algorithm to solve large-sized problems. We run simulations to compare different fronthaul architectures for two deployment areas: dense and sparse.