That’s right, everyone was thinking that LTE and Wi-Fi would compete against each other for center stage in deployments. I know that the carriers favor licensed bands but the customer want bandwidth, they don’t care how they get it. They don’t want to pay too much for the connection either. So here is there the love story begins. They have a common bond, bandwidth for the user. This is something that anyone with a Smartphone loves, bandwidth!
I am hoping to get this out at a time when T-Mobile is making the push for VoWiFi along with the VoLTE. They really seem to moving ahead at full steam with this and I am impressed. Kudos to the OEMs working with them which I think is Ericsson, Nokia, and Cisco. I am sure there are more involved but the way this is rolling out in the urban areas is really impressive! Verizon Wireless has the capability to do VoLTE and it works well. I think the end game is to sunset the 3G network. Not many people are willing to pay more for VoLTE. Sure, it may sound better, but would you pay to sound better? I don’t think that most people would. I think that the real goal is to shut down the 3G system and save all that money. That is my opinion.
I congratulate T-Mobile for pushing the envelope with Voice over Wi-Fi, (VoWiFi). They are realizing how hard it is but they did it and it works! Who knew LTE would push the unification of Wi-Fi bands and the licensed bands even closer. That VoWiFi would be the rage after VoLTE. Actually, in Wade’s World, I see the cable companies pushing VoWiFi because they have it deployed everywhere. What a concept! I can’t wait until we see Wi-Fi only smart phones. We actually have Wi-Fi only tablets that can use apps, like Skype, to make calls over Wi-Fi. This was going to be a solution early on for the carriers with LTE, to have an app make the call, but there were too many issues, especially if there is an emergency, but I don’t know much more about why it didn’t succeed.
This was very hard to research, at least for me, it just gets so confusing and I have yet to find one document that can really explain all of this without crossing lines and adding confusion. Even the Mobile Broadband Evolutions document found here didn’t add much clarity for me. I read this and I think to myself that I used to be an engineer, now I can’t even spell E-N-G-I-N-E-E-R without getting a headache.
If you’re wondering why this is going to happen, then you might not realize that the data demands of the public are crazy! Everyone is using more and more data on their devices. Why shouldn’t they? I mean there was a day when we had to “plug-in” to do anything. There was a day when the only reason to get on a computer was to work. Now, look at all the online communities and all the apps and Facebook. It’s a crazy world full of data demands that will only get worse as people want to watch more and more streaming video on their devices. It’s already happening! Remember when we thought gaming would sink the network, well, let’s look at video. It’s very demanding but only the tip of the iceberg!
So the OEMs had to figure out a way to get LTE and Wi-Fi to play nice together. Really it was Qualcomm who came up with the plan, (with some help from Ericsson), and they have several different ways to do it. Whether you think it’s good or bad, let’s look over the different options.
By the way, most of these will likely be used in a small cell environment, usually inside a building or a stadium where the heaviest data usage happens. I would expect this to be used out on the street unless it’s like a city street with outside seating. This really covers the licensed band sharing the load with the unlicensed band. They will be working together. Now remember that the backhaul is still an issue, so if the Wi-Fi and the carrier share the backhaul then there is a new bottleneck that could constrain data. Just keep that in the back of your mind when reading this.
Wi-Fi offloading – this is how it is currently being done, basically you offload the data to the Wi-Fi if you have coverage. If you make a call or if there is no readily available Wi-Fi, then you use the carrier’s bands.
Wireless Unified Networks or Wi-Fi Integration – Think of Wi-Fi as it is now just working with LTE as a partner. Alcatel-Lucent calls this Wi-Fi boost and Cellular boost. Wi-Fi could provide the bulk of the downlink and the LTE carrier provides the bulk of the upload while providing little download to clean up the spectrum. This would require no change to Wi-Fi as we know it today. Pros are if the Wi-Fi is clean you can use all the bandwidth to carry data, for instance if you are in your home with no interference and the kids aren’t streaming video. The con is if you are competing for bandwidth or the backhaul stinks or if there is interference on the Wi-Fi, then there are issues. This works with your existing Wi-Fi, it’s just an upgrade the carrier has to do on their system and a software upgrade in your Smartphone. This would be up to the carrier to make the changes on their network, the way I understand it.
LWA – LTE & Wi-Fi Aggregation – so here is where it is the similar to the above but the LTE adds a carrier for download, hence the aggregation. This will need the carrier to upgrade the small cell but the bandwidth is increased even more to the device. This may require an upgrade to the Wi-Fi AP. LWA likes to have the Wi-Fi and LTE together, at this time, for synchronization purposes. This will change as evolution happens. I believe this would need to be a new or upgraded device for the end-user, (maybe a firmware upgrade will do it), I am not clear on this right now. Pros are that the speeds should be great and that the Wi-Fi can remain the same. Cons are that the UE needs to be upgraded or changed out. This is being trialed as we speak by carriers and OEMs.
LTE-U – LTE Unlicensed – This is going to work on its own or with LAA, so I thought I would give a brief overview. This works in the 5.8GHz unlicensed band. You know, where Wi-Fi resides. To be clear, it ain’t Wi-Fi but the LTE protocol that must learn to coexist with Wi-Fi. It is literally LTE transmitted in a license free band, probably in the 5.8GHz band in the USA. In theory, it could have 2 to 5 times the throughput of Wi-Fi along with better coverage. The Wi-Fi advocates are worried about interference, which I think is funny because Wi-Fi coverage and interference causing quality issues, so seriously, this is the argument? I know it has listen before talk, but anyone who worked on Wi-Fi and sees about 8 other hotspots in the same area has to realize that interference is there whether you admit it or not. Did you ever try to connect in a train station or airport? Look at all the hotspots on your smart phone and just think that they are all trying to coexist in that one area. To me the one company that I know of that made a great inroad in the problem is Ruckus with their smart antenna technology, pretty cool that they control the signal based on interference. Ruckus has more information here.
LAA – Licensed Assisted Access works with LTE-U, LTE Unlicensed. This is all new equipment, so the investment is in hardware as well as software. Truly a Greenfield deployment, the way I see it anyway. The Wi-Fi access point would be replaced with the LTE-U access point, therefore no Wi-Fi, just LTE in unlicensed bands. This would require a new user device, (new chipset). There are also many issues with how it would co-exist with Wi-Fi. Ericsson has an entire presentation here. The theory is that with carrier aggregation the uplinks and downlinks would all work together in sharing the load. This way you appear to have an awesome pipe, so much data passing through multiple bands that all appear to be one pipe. WOW!
MuLTEfire – which is Qualcomm’s new offering where LTE could be completely unlicensed, but could also work with the licensed band, I really don’t know. It’s very new. Qualcomm is always thinking about how to make better wireless chips. They know they need to build in the WOW factor. I have to admit, I said wow! I see great possibilities with new bands that are lightly licensed because they could open up new markets for backhaul and other last mile services. Remember that 5G is moving ahead and will be here in 5 years or less, Probably arriving around 2020 in time for 5G.
At some point Qualcomm is going to have to pick one or two, but it appears they have all their bases covered, I mean how many more options will they create? Will they promote all of these? I have no idea but Dr Paul Jacobs at Qualcomm probably has a pretty good plan.
I am no expert and this is something that takes some more research. I am learning so much about bringing it all together. The one thing that is really going to help is carrier aggregation. The carriers are trying to make the spectrum they have become more efficient. That is also the theory around densification, it has to add so much value and when spectrum costs billions, yes billions, then you need to figure out how to get the biggest bang for each Mega hertz.
So as you can imagine there are Wi-Fi groups who are not happy about this, I mean after all, Wi-Fi has been around forever and they are constantly updating the Wi-Fi protocol to make it faster and more efficient. I am impressed with how they constantly improve what they have. They have done all they could to make it better for the carriers. They probably worry that LTE-U may replace it. I would think that there is so much Wi-Fi out there that this probably won’t happen. The way I see it, if Verizon Wireless has their way they will be using LTE-U all over so they can improve the customer experience without buying any more bandwidth than they need to.
I hope that helps you figure out what is going on out there. This is moving ahead very quickly but the carriers will test it before releasing it. That doesn’t mean there won’t be bugs but they will make sure it doesn’t affect their systems. To gain more information go to http://blog.3g4g.co.uk/2014/07/la-lte-and-laa.html for great input on this subject. Nokia has more information. You can download Nokia’s presentation here. Another good link, http://www.fiercewireless.com/tech/story/4-standards-cooking-lte-unlicensed-fcc-tech-chief-asks-more-details-verizon/2015-08-05?utm_medium=nl&utm_source=internal.
Be smart, be safe, and pay attention!
Have more to add, let me know.
I am putting a small cell handbook together, it should be out soon. It will be geared towards deployment but a good reference overall. It will have most of what I post but also some extra notes is it. If your interested, feel free to sign up for my newsletter below.
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