Cloud RAN for Mobile Networks—A Technology Overview

Abstract

Abstract-Cloud Radio Access Network (C-RAN) is a novel mobile network architecture which can address a number of challenges the operators face while trying to support growing end-user's needs. The main idea behind C-RAN is to pool the Baseband Units (BBUs) from multiple base stations into centralized BBU Pool for statistical multiplexing gain, while shifting the burden to the high-speed wireline transmission of In-phase and Quadrature (IQ) data. C-RAN enables energy efficient network operation and possible cost savings on baseband resources. Furthermore, it improves network capacity by performing load balancing and cooperative processing of signals originating from several base stations. This article surveys the state-of-the-art literature on C-RAN. It can serve as a starting point for anyone willing to understand C-RAN architecture and advance the research on C-RAN.

5G IoT Industry Verticals and Network Requirements

“…As multiple RRHs can be controlled by one single BBU, this entity has a global overview of the status of all the controlled RRHs and can therefore optimize the radio spectrum exploitation by means of reducing the radio interference and maximizing the spectral efficiency. The C-RAN features are analyzed for instance by Checko et al (2015).…”

A Novel Architectural Concept for Enhanced 5G Network Facilities

“…Existing radio resource allocations remain "inadequate" due to the lack of a centralized coordination, especially in urban areas and environments with high density of users. As a remedy, the Cloud-Radio Access Network (C-RAN) approach [12][13][14] has introduced centralized BaseBand Units (BBUs) for processing both the control and user planes, in order to support flexible scaling and sophisticated interference coordination techniques. However, the significant capacity gains proposed by C-RAN come with a high cost for the fronthaul network since the fronthaul requirements for C-RAN are in the order of 6 Gbps bandwidth for small cell sites and of latency less than 0.5ms Round Trip Time (RTT) [15].…”

5G – Wireless Communications for 2020

“…With cloud RAN [23], these baseband processing units would be moved to a centralized server located in the cloud, and the BS would be just a 'dumb' equipment with RF down/up converters, that would forward the DL(UL) signal to(from) this server. By doing this, the modem resources could be pooled, so that they could run more efficiently and make network maintenance, upgrade and expansion easier.…”