Next Generation Fronthaul Architectures

Centralized processing is expected to bring about substantial benefits for wireless networks both on the technical and on the economic side. While this concept is considered an important part of future radio access network architectures, it is more and more recognized that the current approach to fronthauling by employing the CPRI protocol (Common Public Radio Interface) will be inefficient for large scale network deployments in many respects, and particularly for the new radio network generation 5G. In this paper, an overview is given of currently available optical fronthaul technologies, of recently started activities towards more efficient and scalable solutions, and finally an outlook is provided onto which 5G specific service characteristics may further impact future backhaul and fronthaul networks.