Can Qualcomm broker a peace deal between LTE and Wi-Fi in unlicensed spectrum?

5GHz band: Who will make room for mobile firms?

MWC16 Here’s something you wouldn’t expect to see at Mobile World Congress: LTE and Wi-Fi service providers and vendors together in a room, clinking champagne glasses to celebrate a new technology that will allow the two wireless standards to use the same band of unlicensed spectrum. So it was at the MulteFire Alliance launch on Tuesday.

It was all smiles and congratulations among the group – and there wasn't a whiff of angst among Wi-Fi representatives about LTE invading and wreaking havoc on their unlicensed spectrum turf.

But LTE in unlicensed spectrum is one of the most controversial issues in the wireless industry. Mobile operators are eyeing the 5GHz band used by WiFi providers as a way to extend 4G LTE services indoors without having to tap capacity in their expensive, licensed spectrum. But Wi-Fi stakeholders fear that LTE will cause too much interference and deteriorate Wi-Fi services in the 5GHz band. Last month, the US Federal Communications Commission (FCC) ordered LTE-U tests to help sort the issue.

So how is it that certain Wi-Fi players can be happy about the prospect of sharing their 5GHz band with LTE, as the tone of the MulteFire Alliance event appeared to suggest this week?

MulteFire is different. It’s an LTE-based technology developed by Qualcomm, but unlike current technology attempts, namely LTE-Unlicensed (LTE-U) and Licensed Assisted Access (LAA), it does not require an anchor in licensed LTE spectrum to operate. That means anyone, not just licensed mobile operators, could potentially deploy LTE in the 5GHz band.

Qualcomm first revealed the new technology in June last year, and the MulteFire Alliance was formed in December by founding members Ericsson, Intel, Nokia and Qualcomm. Since then, the group has added more members, including Athonet, Bai Cells, Boingo Wireless, Casa Systems, Ruckus Wireless, and SpiderCloud Wireless.

Now the group is working to get specifications published by the end of this year, which will be based on certain aspects of LAA in the 3GPP’s Release 13 standards and will include the listen before talk (LBT) feature, which is critical for ensuring LTE does not interfere with WiFi.

The alliance claims MulteFire will enable harmonious and fair coexistence between LTE and Wi-Fi as well as other technologies in the 5GHz band and will rely on LBT to achieve that.

“The concern is that any time someone comes in to 5GHz, they have to respect the existing service providers already there,” said Dan Rabinovitsj, COO at Ruckus Wireless. “We lobbied heavily on LAA to ensure LBT took place. But MulteFire is the right step to co-exist with WiFi in a meaningful way.”

Ensuring that peaceful co-existence is a priority for the Alliance as it works on the first specs this year. But according to Durga Malladi, VP of engineering at Qualcomm, “It’s not the end of the world as we know it.”

It’s likely not everyone will agree with that. The group’s membership so far is not exactly widely representative of Wi-Fi industry stakeholders, and notably absent are cable operators. As the MulteFire Alliance’s specifications start to take shape this year, perhaps there will be more industry representatives ready to raise a glass to the new LTE technology this time next year at MWC.®