No standards have been published yet, no network architecture has been decided on, and there are spectrum issues. But operators and kit vendors are convinced that 5G, which should begin rolling out by 2020, is needed to meet the requirements of the much-hyped Internet of Things and connected objects.
According to the mobile industry's current thinking, 5G should provide the illusion of limitless mobile capacity - the ability to share data anywhere and between any devices. The European Union's METIS project predicts that 5G networks will be "at least 10 times faster, accessible in all conditions, efficient in handling very large number of devices, highly reliable, and providing high levels of super real-time experience."
Every ten years or so, a new generation of mobile technology arrives, bringing with it the next wave of functionality and enabling emerging use cases as it does so. 5G, expected to begin rolling out in 2020, is no exception, with mobile operators hoping that its arrival will meet the complex requirements of the Internet of Things (IoT).
Ulf Edwalsson, SVP and group CTO at Ericsson, reiterated analysts' predictions that by 2020, it's thought that 90 percent of the world population and 50 billion devices will be online, so "we do need a network for the networked society".
This trend for both more people and objects to go online, he told the MWC show in Barcelona last week, will require greater spectral efficiency from mobile networks to accommodate the growing number of connections. That will require "a new innovation regime in the industry", said Edwalsson - or a new way of working with other industries to understand their businesses' demands. "Cars are becoming software products and that is a new paradigm," he added.
Historically the mobile industry has only had to work with other mobile firms when designing specifications for the next generation of cellular technology. For 5G, the needs of industries from energy, auto manufacture, logistics, and heavy industry will need to be accommodated. And that's not the only way that 5G is a break from the generations before it.
Much more than access
In a 5G session devoted to 5G services, Mike Short, VP at Telefonica, described 5G as "a special generation".
"It is much more than access," Short said. It's about control as well - the remote operation of sensors, actuators, and so on. Given the new uses which 5G will be put to, more research is needed not just into control, but how to cut latency, improving reliability and resilience - a mobile network can't fail if it's relaying instructions to an autonomous car - energy efficiency, capacity, and quality of experience.
And it's not just operators and networking kit makers that are spending on research: the European Commission has set aside up to €700m in public funding to develop 5G as part of its seven-year Horizon 2020 programme.
"5G represents an opportunity for the telecom sector to reinvent itself. With 5G, telecom operators should be able to provide specialised network services to a series of new industry partners, from the automotive, to rail, health or energy sectors, to guarantee that connected cars will be able to react in less than 1 millisecond and avoid collisions, or that tele-medicine will save lives and not be stuck in traffic," European commissioner for the digital economy Günter Oettinger told MWC.
The commissioner told a panel at the show that Europe stands to take a leadership position in 5G. "The competition is global and fully open, but Europe is in a good position. We are competitive for the next five to seven years," he said.
Europe may fancy its chances, but it's likely to be Asian operators that are first to rollout 5G networks in time for the 2020 Olympics.
However, some are already looking further out. Seizo Onoe, CTO at NTT DoCoMo, noted that an experimental 5G network in Japan's Kanagawa prefecture yielded download speeds of 4.58Gpbs using millimeter wave spectrum. He expects 6G to arrive in 2030.
While almost all aspects of 5G were picked over at MWC this year, there was one that was conspicuously absent: none of the speakers discussed how much 5G deployments would cost, nor how much operators would charge for its use. "What is important is having a continuous flow of technology. Then business models will evolve," said Ericsson's Edwalsson.
There may be a simple reason for that: while some in the industry are looking towards 5G, others are hoping to get more mileage from the current generation of mobile technology.
According to estimates from the mobile industry's trade association the GSMA, operators plan to spend another $1.7tn on rolling out 4G infrastructure before 2020, the year 5G networks will start appearing in earnest.
While some in the industry have one eye on 5G and 6G, most are focusing on building out the current generation of mobile tech.
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