An SDR-Based Experimental Study of Reliable and Low-Latency Ethernet-Based Fronthaul with MAC-PHY Split

Abstract

Cloud-Radio Access Network (RAN) is one of the architectural solutions for those mobile networks that aim to provide an infrastructure that satisfies the communication needs of a wide range of services and deployments. In Cloud-RAN, functions can be flexibly split between central and distributed units, which enables the use of different types of transport network. Ethernet-based fronthaul can be an attractive solution for Cloud-RAN. On the one hand, the deployment of Ethernet-based fronthaul enables Cloud-RAN to provide more diverse, flexible and cost-efficient solutions. On the other hand, Ethernet-based fronthaul requires packetized communication, which imposes challenges to delivering stringent latency requirements between RAN functionalities. In this paper, we set up a hardware experiment based on Cloud-RAN with a low layer split, particularly between medium access control and the physical layer. The aim is to demonstrate how multi-path and channel coding over the fronthaul can improve fronthaul reliability while ensuring that: (i) latency results meet the standard requirements; and (ii) the overall system operates properly. Our results show that the proposed solution can improve fronthaul reliability while latency remains below a strict latency bound required by the 3rd Generation Partnership Project for this functional split.