What is millimeter wave 5G?

I’m completely convinced that 2020 will be the year of 5G. All the major carriers started the year with some sort of 5G presence, and I expect that by the end of the year there will be a 5G phone that practically anyone will want. (Whether anyone can afford it is a different matter completely, but I think that will work itself out.)

Still, practically all the 5G being rolled out this year will be in the low and mid bands. Let’s take a look at what that means, and what “millimeter wave” 5G really means.

Before we look forward, first let’s look back.

5G isn’t just an extension of 4G or LTE. It’s a complete reworking of how cellular communications work. The last time this was done was practically a decade ago, as carriers transitioned from 3G to 4G. Since there was no real law saying carriers had to name these things properly, pretty much all of them started labeling their upgraded 3G service as 4G. True 4G started to come to consumers and carriers called it “LTE.” This wasn’t 100% accurate either as it took years before carriers fully implemented the LTE-Advanced standard. But no one cared because data speeds got better and better. For years I’ve been saying that I really don’t care what they call it as long as it works better. And it did.

Real 5G started to be implemented in 2017. The FCC, the government agency that regulates all broadcasts in this country, started taking away unnecessary TV channels to make room for 5G. They then started auctioning off licenses for these frequencies. The biggest winner in that auction was T-Mobile, who then started building a 5G network using the 600MHz range. AT&T also started implementing 5G at 600MHz, but also started using licenses it already had in the 800MHz range.

The road to millimeter wave

There have always been two paths to 5G. It’s always been the plan to use spectrum in the 500MHz to 1GHz range to get 5G moving. However those frequency ranges are going to be crowded when people start to really embrace 5G.

There’s nothing terribly wrong with that “mid-band” spectrum. It’s just that people have been broadcasting there for 75 years and there is only so much room. As people begin to consume more data, they’ll clog up those frequencies a bit more. I still believe that at its most congested 5G will still beat LTE. But if you really want that super-fast speed you’ll want to talk about millimeter wave 5G.

Millimeter-wave 5G uses a lot of unused space in the Ka band from 26-40GHz. This area has just been opened up for cellular and there is a lot more space for growth. Using millimeter-wave 5G will really supercharge the phone experience… eventually.

The good stuff just keeps coming

With plenty of spectrum to play with, millimeter-wave 5G should have awesomely low latency. Latency, as I’ve said before, describes the time difference between when you ask for something and when you get it. It’s really more important than raw speed. Because the average web browsing experience includes dozens of individual requests, low latency will really make the browsing experience seem much much faster.

Low latency will also allow for faster decisions. It will be easier and safer to use 5G cellular to help drivers make decisions based on complex logic. It will make gaming even more realistic. There’s nothing bad about low latency.

Except that millimeter wave 5G is really hard to do.

The technical issues with millimeter wave 5G are tough to get through. As a general rule, the higher the frequency, the more energy it takes to send a broadcast on it. It doesn’t matter how fancy your computer chips are, this is a fact and isn’t going to change. So the biggest issue with millimeter wave 5G is that it takes a lot of power and that would mean much bigger phones or short battery life.

We saw this same issue when LTE first rolled out. It is possible for the radios to get more efficient, up to a point. However, the easiest way to keep battery life decent is to decrease broadcast power. In order to do that, you’ll need towers that are much closer together.

It’s believed that in order to get good coverage with millimeter wave 5G you’ll need towers 500-800 feet apart. Compare this to current cell tower spacing which tends to be about a mile apart in less populated areas. Denser areas like cities need more towers, not because of range but because each tower can only handle so many calls.

It won’t be too difficult to put all those towers in cities, especially since each tower can be a lot smaller than the ones used today. In suburbs, I expect carriers to make deals with cities to put towers on lightposts. These towers are already starting to show up in some places and they’re really not noticeable unless you are looking straight at them.

And then there’s penetration

The other issue with millimeter wave 5G is that the waves really don’t do a good job at all getting through buildings. This is the same frequency range used by DIRECTV Satellite and that’s why the dish is on the roof. In order to have millimeter wave 5G inside, it’s likely that you’ll need some sort of booster system.

But the benefits are amazing

In addition to enabling things like smart freeways and augmented reality, there’s a lot to love about the 5G experience. You’re already starting to see 5G in stadiums, which is a natural fit. Imagine an augmented reality, multimedia experience for people watching the game. Team owners have finally realized that people still want to use their phones while watching what’s going on live. I expect there to be a lot of movement in that area as soon as we see more 5G phones.

When will 5G be right for you?

As I said at the beginning of the article, I think this is the year of 5G. If you’re looking to upgrade your cell service, you may want to look at a phone plan that lets you trade in your current phone after 6 months. You can get 5G phones now, but there will be more alternatives by the summer. In the meantime if you’re looking for that upgrade, this is a great time to do it. The prices and deals are awesome. If you don’t believe me, call the folks at Signal Connect at 866-726-4182 and find out what AT&T can do for you. If it’s after east coast business hours, fill out the form below and our experts will contact you, usually within one business day.

About the Author

Stuart Sweet
Stuart Sweet is the editor-in-chief of The Solid Signal Blog and a "master plumber" at Signal Group, LLC. He is the author of over 6,000 articles and longform tutorials including many posted here. Reach him by clicking on "Contact the Editor" at the bottom of this page.