MuLTEfire plans slow burn for unlicensed "LTE-like" networks

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Given the seemingly endless surge in connected devices, the conundrum facing operators is that the more capacity that is built into a network, the more users will consume data.

The time has well passed for trying to put the genie back in the bottle, so where can operators turn? To the estimated 500MHz of free spectrum that lies in the 5GHz band, according to industry consortium MuLTEfire.

Comprising the likes of Qualcomm, Intel, Ericsson and Nokia, the group is aiming to offer an LTE-like experience without the need for any spectrum. This is a prospect that sounds too good to be true, but the group is at work on specifications that will be issued in the fourth quarter of this year.

Its origins lie in LTE-LAA, the form of carrier aggregation that brings together licensed and unlicensed spectrum and is based on 3GPP Release 13.

MuLTEFire aims to go one further, by offering a comparable service without the need to buy spectrum. Instead, the view is the likes of stadiums, public venues and university campuses could use an army of small cells to connect previously unconnected areas.

Speaking to Mobile Europe, Mazen Chmaytelli, Senior Director of Small Cells Business Development for Qualcomm Technologies, says the priorities for the alliance include determining ways of ensuring interconnect between MuLTEfire networks and more conventional mobile networks.

Ultimately, he says deployment will be "plug and play", in line with the hope that it will be venue owners behind adoption of the technology.

Backhaul will be handled through traditional means, a simple statement Chmaytelli accepts hides more challenges. He says: "As users demand more data, we need to solve the issue of backhaul. It's an issue across any technology."

But how close to LTE will MuLTEfire be? Chmaytelli says: "You get what you pay for, like guaranteed quality of service. This is a proven benefit that having your own unencumbered spectrum gives you.

"With unlicensed, a lot of the technology will be used in such a way that it's very important to share in the right way and manage interference. Licensed spectrum is still at the top of the hierarchy."

The importance of sharing is particularly key, when you consider how many sectors already rely on unlicensed bands. Advocates of LTE-U have had to be at pains to stress they will act as good neighbours, amid fears that these kinds of technology amount to little more than a landgrab.

[Read more: Cynical response to LTE-U shows tech has a steep hill to climb]

Chmaytelli smiles when reminded of the reception a fellow Qualcomm exec received at last year's Wi-Fi Global Summit to LTE-U and accepts MuLTEfire will also need to play nice with others. He argues suggestions MuLTEfire or LTE-U would squeeze out the likes of Wi-Fi companies miss the point.

He says: "We've come a long way from that forum. That side of the industry was very worried about LTE players coming onto their turf.

"If you look at Qualcomm for example, we have leading in the Wi-Fi and LTE spaces. We are providing a lot of chipsets and routers to Wi-Fi companies. As a tech company, we don't want to disrupt another part of our own business. This kind of debate helps us to co-exist better."

Central to this playing nice is using ETSi-defined listen before talk standards. Already present in Japan and Europe, the tech ensures the fair use of unlicensed bands.

However, the telecoms industry is littered with good technology that fails, without anyone exactly knowing why. Chmaytelli said this himself at a MuLTEfire panel at last week's Mobile World Congress, noting how there have been plenty of "nice ideas" that don't get off the ground.

This is perhaps why he is coy on exactly when the first MuLTEfire trial or deployment will take place. The priority is building its membership base ahead of the Q4 specifications. As the panel noted, a standards-based and interoperable technology will achieve more scale than one that is neither.

In the meantime, 5G, with its promise to connect ultra-dense networks, will take more shape. Is there a fear than MuLTEfire could miss its chance in its attempt not to upset anyone?

Chmaytelli suggests the lack of need for a licensed anchor means MuLTEfire will remain compelling. He says: "As any tech gets deployed there's always sceptics but I think the proof will be in the pudding. There's a collective brain power to make it happen." We will see in the autumn.