AT&T's Keathley shares a 5G vision that includes LTE-A, Wi-Fi, SON and more

Tom Keathley, AT&T

Keathley (Source: AT&T)

With Tom Keathley, Senior Vice President of Network & Product Planning, AT&T

With just a few weeks on the job, Tom Keathley is already well-versed in all aspects of AT&T's (NYSE:T) network. Keathley, a long-time AT&T veteran, was named the company's senior vice president of network and product planning replacing Kris Rinne, who retired at the end of November. Keathley recently spoke with FierceWirelessTech Editor in Chief Sue Marek about the company's progress with carrier aggregation and VoLTE and shared his vision of 5G and the future of the wireless network. The following is an excerpt of that conversation.

FierceWirelessTech:  How are you settling into your new role as SVP, network and product planning at AT&T?  

Tom Keathley:  I've just been doing this for a couple of months.  I am settling in well but I miss having Kris [Rinne] around. [Rinne retired as SVP of network technology at AT&T in November]. 

FierceWirelessTech: I was just at AT&T's LTE Broadcast demo at AT&T Stadium in Dallas during the National Championship football game. You have digital rights already secured with content providers for the U-Verse product. Do you see the potential for that moving content like that to LTE broadcast?

Keathley: Let me start with LTE Broadcast technology itself. Since it is a broadcast technology it gives us the option to take any kind of video stream and multicast it to multiple users in the same spectrum swath. LTE Broadcast would give anyone using it the capability to deliver a linear service. That said, there are no plans to launch a linear service using LTE broadcast but that would afford us the ability to do so if we elected too.

FierceWirelessTech: You're on the board of the Next Generation Mobile Networks (NGMN) alliance, which is working on 5G.  When we talk about 5G, what do you envision that being? 

Keathley: As you know there are no definitions or standards actually around what 5G will be. I am expecting that like with 4G, it will be defined by the ITU at some point. But frankly I don't know if there is a time frame by the ITU about putting out a definition for 5G.

What we envision is more or less what we know about the technologies that are involved, what the use cases are and what the requirements will be. With that disclaimer, if you look at 4G, 4G was primarily related to the LTE air interface. Launching it from operator's perspective and then evolving it into LTE Advanced.  4G was pretty cut and dried. It was related to LTE.

With 5G, I don't envision 5G outcome to be related strictly to an air interface like 4G was.

FierceWirelessTech: Isn't that why 5G is tricky. In the past 2G, 3G, 4G were all related to air interface.

Keathley: Yes, that's how it was and that's how it has always been. But if you look at the evolution of this industry, it's going to not only include the high speed, high bandwidth requirements you will see with LTE Advanced. It's also going to include Internet of Things requirements for low-powered low-data devices, ultra-long battery life plus dense capacity in urban areas.  These requirements probably won't be handled with just one air interface or one spectrum band. It will be a network of networks.

We will still be using LTE Advanced along with things like Wi-Fi, potentially a low-powered network, potentially a millimeter wave network that will add capacity in the millimeter wave band in the 10+ Gig range. And then it will likely have SON HetNet capabilities to provide seamless interoperability between those networks. 5G will also touch on contextual awareness.

It will have different requirements and no single air interface will provide all those user expectations across the board.   It will be a different definition from what you saw with the 2G, 3G and 4G definitions.   

FierceWirelessTech: Do you think this is going to involve different types of companies than what have traditionally be in the wireless ecosystem?

Keathley: I think that is possible but not necessarily a requirement. If you look at AT&T's assets, I believe LTE Advanced will be a big part of what 5G offers as will Wi-Fi. Small cells, DAS, SON capabilities that interface those will be a part of 5G. Antenna technologies like massive MIMO that will give us high capacity and spectral efficiency and venue locations.  We can deliver all those in a 5G scenario.

Maybe the low power wide area network part of 5G is something that could conceivably come from us or another player.  I would not say an operator couldn't deliver a full 5G experience if they desired to do so.  And frankly I think we are one of the operators best positioned with our assets to do that.

FierceWirelessTech: Isn't millimeter wave technology pretty experimental at this point?  It seems that this technology is a potential area for some startups.

Keathley: I do agree this is possible. But it's mainly unlicensed spectrum in that space.  Our traditional vendors could build to it. Or new vendors could build to it. It doesn't necessarily mean that we will have all new players in that space.

FierceWirelessTech: Traditionally operators have been comfortable staying with the same vendors for continuity because those vendors knew the existing network. Do you think that will happen again?

Keathley: 5G as I've defined it may create some opportunity that may not have been available in the other environment.  It is very easy to move from 2G to 3G to 4G with the same suppliers because they know the network and there is synergy.  But if millimeter wave becomes a big part of 5G--which is quite possible--there could be new players in the ecosystem in that space.

FierceWirelessTech:  AT&T has been deploying carrier aggregation. Can you give me an update?

Keathley: We are continuing the deployment of carrier aggregation in a significant way. Last year you heard we had a handful of markets.  We generally don't say the number of markets because markets are hard to define.  But we now have a lot of big markets deployed like New York, San Francisco and Dallas are deployed and that deployment will continue in 2015.

FierceWirelessTech: You have to seed your user base with LTE-Advanced capable devices to take advantage of carrier aggregation. How is that going?  

Keathley:  Yes we need to make sure we migrate it across our entire device portfolio--or at least all the good high end devices. We are almost to 20 LTE-Advanced devices.

FierceWirelessTech:  Can you also give me an update on AT&T's VoLTE deployment?   

Keathley: Similar to carrier aggregation, we don't list markets but the VoLTE rollouts continue and I expect them to continue into 2015 until we finish all of our LTE footprint.