5G C-RAN Architecture: A Comparison of Multiple Optical Fronthaul Networks

The development of the fifth generation (5G) wireless technology is in progress to address the increasing demands for high capacity, low latency, and ubiquitous mobile access instigated by next-generation mobile and machine-centric applications. The Centralized/Cloud-Radio Access Network (C-RAN) architecture exploiting the small-cell paradigm has been identified as a promising approach to address the benchmarks of 5G networks. However, providing a reliable, cost-effective, and quality of service guaranteed end-to-end connectivity is one of the major challenges in 5G C-RAN. To identify the suitability of a fronthaul technology to satisfy the unprecedented demands of future 5G wireless network in a cost-effective manner, different architecture and technologies need to be equitably compared in terms of all major requirements of 5G fronthaul network such as bandwidth requirements, delay budgets, deployment costs, complexity of radio remote head (RRH), and the ability to support advanced wireless functions. Therefore, in this paper, we equitably compare a multiple fronthaul architectures that can be used for 5G networks. In particular, we first analyze the stringent requirements of the 5G fronthaul network. Then, we investigate the applicability of three fronthaul technologies (PLS, ARoF, and CPRI) for the C-RAN architecture. We provide comparative analyses of these technologies by elaborating on their ability to fulfill 5G latency and capacity requirements, the complexity of RRH, and also to support advanced wireless features such as cooperative communication. To provide a well-balanced comparison of these fronthaul technologies, we also comparatively analyze the deployment costs of these architectures by developing an optimization framework to plan 5G C-RAN. Our analyses provide insights into how a future-proof fronthaul network can be modeled for 5G C-RAN.