Frequency frustrations precede inevitable arrival of 5G

14 Feb 2017

Image: hin255/Shutterstock

A recent project in Finland may have eased the burden on cities as 5G convergence nears a reality, but all it buys us is time.


5G is on the way, of this we are sure. For those wondering what’s to come, take a look at how the Winter Olympics in Seoul are handled next year – the South Korean capital will be the test bed for numerous aspects of the next generation of connectivity.

However, there are obstacles to 5G throughout the world; obstacles significant enough for the EU to sweat over a low-key, barely reported project held in Finland last September.

For 5G to come on stream, we need to work out what frequencies connected devices can operate on. As the internet of things (IoT) shifts from annoying buzzword to multi-device reality, there is a strain on our already loaded networks.

It has been suggested – and pressed by the EU – that the 700MHz band should be set aside for mobile communications. This is a massive undertaking and one that puts significant hardship on services currently operating at 694-790MHz.

Digital Terrestrial TV (DTT) services in Ireland, and throughout Europe, are the majority of those set to get the boot – but do they really need to move?

According to former fears, yes. If connected devices are loaded into an already heavily populated frequency band, interference will ensue. Worse still, DTTs are destined to be phased out, with internet-based TV eating into their market even before 5G comes along to put the final nails in the coffin, from Stockholm to Madrid.

That’s why DG Connect (the EU group focused on communications networks, content and technology) took a keen interest in a Finnish project last September.

Finnish line

On 2 September 2016, Finnish public broadcaster Yle, in cooperation with Qualcomm and Nokia, successfully demonstrated mobile supplemental downlink (LTE SDL) technology in the UHF band.

This means that interference was manageable, there’s more room than previously thought and, for now, the rush to vacate may not be needed.

“Europe is very much different in terms of its use of broadcasting spectrums,” said Roberto Viola, director general of DG Connect, when talking with

“In some countries, there is little digital terrestrial TV, like in the Nordic countries, but there are countries where more digital terrestrial TV is still used; Ireland and Spain, for example.

“So if you have digital terrestrial TV, there should be a good assurance that this can go on for a while. [But] at the same time, why not use the free parts of the spectrum for advanced services?”

Image: Afterfocus Studio/Shutterstock

Image: Afterfocus Studio/Shutterstock

Surprise win

Viola assumed the Finnish project would fail, given the understandable reluctance to back multiple, often critical, technologies working together in harmony.

“We said ‘no’, but let’s try it out,” he explained.

“The trial demonstrated that they had over 1GB in downlink, while people still received TV. So there are a lot of things you can do while still guaranteeing TV services.”

Viola noted that several elements are now possible: setting priorities while allowing downlink flexibility; ensuring co-existence and convergence of today’s and tomorrow’s wireless services; and providing a win-win model for others to follow.

However, the interference clear-up might not be complete. A study in Brazil in the same time period as the Finnish project found that varied situations produced varied results.

For example, researchers set an accepted target of 5pc interference when running multiple devices across the 700MHz band. In one setting, which had a digital TV system covering 10km, LTE cells with a 2km radius and 21 LTE users by sector, staying below the limit was easy.

When the TV coverage radius was increased to 20km, the probability of interference went above the accepted norm.

Good to know

This appears to show that the Finnish trial was successful, but cannot be relied upon forever. Strain will bring more interference. If anything, this model merely showed us the rush to vacate the 700MHz band might not be necessary in the immediate term.

Indeed at the end of 2016, Irish Communications Minister Denis Naughten, TD, revealed that Ireland’s 5G mobile broadband auctions using 700MHz spectrum will take place in 2019, ahead of the rest of the EU by one year.

ComReg is in the process of finalising a process to allocate spectrum in the 3.6GHz band in early 2017. This will increase wireless spectrum in Ireland by 86pc.

As well as this, the Irish Government has allocated €8m in Budget 2017 to facilitate the migration of broadcasting services from the 700MHz spectrum band to clear the way to license 5G spectrum to operators.

“Technology-driven innovation calls for smart regulation, bridging the present and the future,” said Viola.

“Broadband, broadcast [and] audiovisual are becoming convergent domains in the digital age. So is their spectrum use.

“The Commission’s strategy for the sub-700 MHz band is to safeguard the development of broadcasting, and also to allow innovators to invest and drive benefits and efficiency.”

Gordon Hunt was a journalist with Silicon Republic