What Is Open RAN Technology? And What Does It Mean for 5G?

March 25, 2020 by Matthew Innes

Openness and intelligence are the names of the game at the O-RAN Alliance.

The multinational telecom carrier Telefónica has tapped Xilinx and a host of other hardware and software companies—including Altiostar, Gigatera Communications, Intel, and SuperMicro—to advance O-RAN, or open radio-access networks, within Telefónica's 4G and 5G wireless network. These improvements are projected to take place throughout the UK, Germany, Spain, and Brazil this year.

But what is Open RAN anyway? And how might it make a difference at a timely moment with the roll-out of 5G? 


Open-RAN vs. Traditional RANs

O-RAN technology is said to allow service providers to speed up 5G network development through its open architecture.


O-RAN Architecture

O-RAN architecture. Image used courtesy of the O-RAN Alliance

There are several other benefits of O-RAN technology over traditional RANs, according to the O-RAN Alliance. The O-RAN Alliance is comprised of a network of major industry players including Telefónica, AT&T, and Verizon. These giants driving the development of O-RAN technology have two core principles to define O-RAN and distinguish it from other RANs.

The first is its open interface, which the O-RAN Alliance’s whitepaper says will allow smaller vendors to introduce their own services and allow operators to customize the network as needed. It will also allow multiple vendors to deploy their technology on the network, thereby enabling competition and reducing costs. 

The second core principle of O-RAN is intelligence. The deployment of 5G and the applications that come along with it will increase network complexity to the point that it is no longer viable for humans to operate and optimize the network. The network must be able to operate on its own and learn as it goes along, which is why the O-RAN Alliance calls for embedded intelligence at all levels of the network.


O-RAN Initiatives and the Push Toward Off-the-Shelf Hardware

The O-RAN Alliance's white paper on use cases and deployment scenarios outlines three main initiatives of O-RAN: 

  1. Blaze a trail toward RAN virtualization, open interfaces, and AI-capable RAN
  2. Minimize proprietary hardware and promote a push toward merchant silicon and off-the-shelf hardware
  3. Specify interfaces and APIs to drive "standards to adopt them as appropriate" and explore "open source where appropriate"


Diagram of the overall logical architecture of O-RAN

Diagram of the overall logical architecture of O-RAN. Image used courtesy of O-RAN Alliance

The alliance's commitment to minimizing proprietary hardware reflects their efforts to make the network more accessible to a broader range of hardware designers. Instead of having to integrate specialized hardware in their designs, engineers can use off-the-shelf hardware to deploy their technology with O-RAN. Furthermore, cutting back on propriety hardware will drive costs down and allow a broader supply chain to provide materials, thereby enabling faster implementation of new technology.


Making Way for 5G Base Stations

The O-RAN Alliance explains that its open interface could support white-box hardware design and development. Specifically, the alliance has promised reference designs for white-box base station hardware. To enable both baseband units (BBUs) and remote radio units (RRUs), the alliance has also mentioned reference platforms, which will provide a decoupled approach along with detailed schematics for hardware and software architectures.

This will help engineers in the telecom sector to design energy-efficient base stations, especially as 5G rolls out. An additional goal of this use case is to reduce the research and development costs that may prohibit smaller companies from entering the telecom industry. 


O-RAN Players

The open architecture of O-RAN is designed to give as much freedom as possible to designers in order to encourage innovation in the industry. To this end, the O-RAN Alliance is paying considerable attention to attracting industry players as partners.

Since the O-RAN Alliance is relatively new, having been founded in early 2018 by AT&T, China Mobile, and other telecom giants, there is still significant room for improvements on both the hardware and software sides of the technology, many of which will likely be explored by some of the smaller players or newcomers to the industry.


O-RAN Alliance members

O-RAN Alliance operators. Screenshot used courtesy of O-RAN Alliance

Aside from those already mentioned, notable members of the O-RAN Alliance include T-Mobile, SK Telecom, Sprint, and China Telecom. The contributors of the alliance have some big names that will be even more familiar to engineers: Analog Devices, IBM, Infineon, Keysight Technologies, Nvidia, NXP, Qualcomm, Samsung, and Texas Instruments, among others. 


Feature image used courtesy of O-RAN Alliance


Do you think 2020 will be the year of 5G? Share your thoughts in the comments below.