While the RAN’s air interface has seen huge innovation over the past two decades, the underlying structure of the radio network has changed far less. Cells have got smaller and smaller, but any attempt to change the distributed layout for a centralized, virtualized approach has run up against a key barrier ‘ the amount of fiber needed to connect thousands of cell sites to the center. A few carriers have access to that volume of fiber (notably China Mobile), and ‘wireless fronthaul’ technologies will be suitable for some scenarios, but most operators’ centralized RAN attempts have stopped short at a fairly localised base station hotel.
A start-up called Phluido claims it has a new way to solve the problem, which could help make it as viable to virtualize the RAN in the cloud as the packet core. Founded by former Qualcomm engineers Dario Fertonani and Alan Barbieri, Phluido has developed a technique that allows the network to pre-process and compress the frequency data at the cell site, so that it can be realistically transmitted to the data center via a lower performance connection such as an Ethernet cable or microwave. Once there, the baseband processing would take place, running as an application on centralized servers.
‘Currently the most expensive piece of equipment in the mobile network is the baseband processor,’ Fertonani told GigaOM, which selected Phluido as a finalist in its Structure Launchpad contest. ‘Once we can prove that we can move the baseband processor to the cloud, then a lot of new business models open up.’
Most interesting, those include offering radio capacity ‘as a service’, mirroring efforts to do that with unlicensed WiFi, in order to support a wider range of service providers more flexibly (see separate item on BandwidthX). Phluido, or more likely a larger operation capable of creating alliances with large cellcos, could operate the cloud-based pool of capacity on an on-demand basis for participating operators. These would build out slimmed-down cell site antenna/radio units armed with the Phluido technology, and these could tap into the cloud platform when they needed additional capacity.