What Does '4G' Really Mean, Anyway?

IRA FLATOW, host:

This is SCIENCE FRIDAY from NPR. I'm Ira Flatow.

Last week, you recall, we took a look at the electronic gadgets coming out of the Consumer Electronics Show, and one of this year's big, buzzy things was the talk about the 4G network. Sprint, AT&T Mobile, Verizon, all have 4G now, but what exactly does 4G mean? Because if you peel off that 4G label, they work differently, and in some cases, those technologies aren't even running at the same speeds. But the networks are still advertised as 4G.

So what's the difference? And why are even the fastest networks in the U.S. so much slower than networks in places like Sweden and Australia? If the technology is there, why isn't it here? What do you think?

Do you have a 4G network already? Let us know. Our number is 1-800-989-8255, 1-800-989-TALK. And as always, you can tweet us, @scifri, that's @-S-C-I-F-R-I, or go to our website at SCIENCE FRIDAY and get in on a conversation there.

Chris Ziegler is the senior mobile editor at Engadget in Chicago. He joins us by phone. Welcome to SCIENCE FRIDAY.

Mr. CHRIS ZIEGLER (Senior Mobile Editor, Engadget): Hey, Ira, how are you?

FLATOW: A lot of folk - a lot of 4G at that electronics show, was it not?

Mr. ZIEGLER: Yes, yes, every American carrier was talking 4G there.

FLATOW: And is there a common definition for what 4G means?

Mr. ZIEGLER: You know, it's interesting. There actually is. There is a technical definition that's controlled by the ITU, which is a body that's run by the U.N. And people might be amazed to discover that no current network advertising itself as 4G actually meets those requirements.

(Soundbite of laughter)

FLATOW: No kidding?

Mr. ZIEGLER: That's true, that's true.

FLATOW: The U.N. controls the requirements, and no one meets it. So what does it mean? When they're saying 4G, what are they actually talking about?

Mr. ZIEGLER: Well, what they're referring to - the biggest and most consumer-noticeable part of that definition is the fact that they're looking for speeds of one gigabit per second down to your device when you're stationary and 100 megabits per second when you're mobile because it is actually harder to transfer data when you're moving than when you're standing still.

So that's what they're looking for, and the only proposed standards that meet that definition are WiMax 2 and LTE Advanced, and neither of those standards even exist yet in a commercial network.

FLATOW: Well, isn't AT&T supposed to deploy LTE later this year?

Mr. ZIEGLER: They are, but there is a big difference between LTE and LTE Advanced, unfortunately. But yeah, so what AT&T is doing, they have the most confused message of all the American carriers, I believe, because basically what they've done is they responded to T-Mobile.

T-Mobile recently launched what's called HSPA Plus, which is an evolution, a very advanced evolution of 3G that we've had for a few years now, that can go up to 21 megabits and beyond, which easily rivals what you can get in your home with, like, a broadband connection.

So what AT&T did is they said, well, hey, we have HSPA Plus, too. We can't let T-Mobile get away with calling their network 4G, and we're not. So we're going to rebrand that network as 4G. But we're also launching LTE later this year. So we're going to bundle that all into one package.

FLATOW: Is this purposefully made to confuse us, all this different technology?

Mr. ZIEGLER: Well, you know, believe it or not, all the executives and marketing folks that I've talked to at these companies insist that they do it to simplify things for consumers, not to complicate things. They don't want to talk about HSPA Plus or LTE because they, you know, they very rightfully say that people don't care.

And they don't. That's true. People absolutely don't care. They just want fast data. They don't care how they get it. So they're trying to use these G-labels as, you know, an equivalency - excuse me - an equivalency rating. They just want people to know: Hey, this is, you know, this is as fast as Verizon's network, so we're going to call it 4G, just like Verizon.

FLATOW: And so the basic thing to know is that whatever the new thing is, 4G, whatever technology it is, it will be faster than 3G, better?

Mr. ZIEGLER: That's right. Yes, that's right.

FLATOW: So that's the take-away message, that if you go in and get a cell phone, that's what you're asking for?

Mr. ZIEGLER: That's right. If you get a 4G device, you will absolutely get a faster data experience. You'll load websites faster. You'll be able to use services like Pandora faster. You'll do all of that. You'll have a cleaner and faster experience with a 4G device, regardless of the carrier.

And right now, today, all of the carriers will give you roughly the same experience with the 4G network. Over time, that'll evolve, and you'll see some of these newer technologies, like LTE, evolve faster and better, and those will get much, much faster.

I'm sure that the marketing groups will say, well, you know, you want to call that four-and-a-half-G, maybe you want to call that 5G. We'll see what they do. But for now, 4G is 4G is 4G.

FLATOW: Let's talk about another bit of technology babble that came out, something called WiMax. What is WiMax? How does that work?

Mr. ZIEGLER: Yes, so WiMax is the, quote-unquote, "4G technology" that's in use by Sprint. And they have a few devices available right now that make use of WiMax. They have the HTC EVO 4G, which they've been advertising very heavily, I'm a sure a lot of folks are aware of. They also have the Epic 4G from Samsung and a couple others.

And it's - it's one of the older next-generation data technologies, but it's very robust. The one disadvantage that Sprint has is that they use a very high frequency for transmitting that data. And there's a concept of physics by which they higher you go with frequency, the harder it is for this RF to penetrate buildings.

FLATOW: Right.

Mr. ZIEGLER: So they're operating at 2,500 megahertz, and it's very, very difficult for that signal to penetrate deep inside buildings. Whereas Verizon and AT&T, for their 4G networks, are both using 700 megahertz, which is much lower, and it's easier to get deep inside buildings.

FLATOW: Do you have your favorite recommendations for 4G network or how you would like to see it work?

Mr. ZIEGLER: Well, you know, what I tell people, that they, unfortunately, they do need to experiment with all networks. You know, just go into a store and experiment with devices and see which is faster in their market because it does vary a lot by market.

What's fastest in New York might be the slowest in San Francisco and might be, you know, middle-of-the-road in Chicago. You just don't know. And it also varies a lot in rural areas, too.

FLATOW: Now, as I mentioned earlier, in the billboard here, other countries have wireless networks that are much faster than ours. Why is ours so much slower?

Mr. ZIEGLER: Well, there are a couple reasons for that. One is that the U.S. has really, really led the push into high-bandwidth, high-experience smart phones. Even though countries like Japan and a lot of countries across Europe have been pushing the benefits of smart phones for longer than the U.S. has, devices like the iPhone have really grown up and taken root first in the U.S., and that has pushed wireless broadband adoption faster than pretty much anything else.

So we consume a lot and a lot of data here. And what carriers are struggling with is coming up with enough backhaul, and that's connection between the cell tower and the Internet backbone. They're struggling to come up with enough bandwidth there for these devices.

And they're also struggling to come up with enough spectrum to connect the cell tower to the phones. So these are the kinds of bottlenecks that we're dealing with here that they're not dealing with as much yet in other countries.

FLATOW: Is it a good thing that we're seeing all these new cell phones coming out? You know, the iPhone was ruling for a while, and now we have, Android has taken over in sheer numbers of phones. And now you have iPhone available on Verizon, as well as AT&T. This is all good in competition?

Mr. ZIEGLER: It's absolutely good for a couple reasons. One, I think it's always great when you have a single device that's available across multiple carriers because that means that you don't have to say, well, you know, I want an iPhone, that means I have to use AT&T, I have to break my contract with X carrier and go to AT&T. A variety of carriers is always a good thing.

But then also, this rapid adoption of high-bandwidth smart phones has really pushed the FCC and the trade organization that rounds up all the carriers to push for - to get a lot of additional spectrum freed up that we can use for these phones in the future.

So the FCC has pushed very hard to free up about a half-gigahertz of spectrum, which is a lot of spectrum, over the next decade or so, and that's going to help a lot with the bottlenecks we're facing.

FLATOW: It appears that the phone is morphing into more of a digital device rather than a voice device.

Mr. ZIEGLER: Absolutely, yeah. That's absolutely true. Over the past couple years, we've seen the rapid adoption of, like, full-QWERTY keyboards, for example, on phones. And I think that speaks to the fact that people are texting as much or more than they're talking now, and that certainly didn't used to be the case.

And, of course, these large touchscreens make it really each to use apps and browse the Web. And these are all things that, you know, instead of talking to your friends on the phone like you might have 10 years ago, now you just send them a post in Facebook, for example.

FLATOW: Do you think we're going to come up with some standard rating for all these various wireless technologies, that we'll really be able to measure each one?

Mr. ZIEGLER: Unfortunately, I don't. I haven't seen any government or trade organization step up to say hey, we need to really lock this down. I think that it's going to be up to marketing organizations within all these companies to come up with logical, sensical standards. I don't know if we can trust them to do that.

But I have to admit: Even though the 4G definition that they're using right now isn't technically accurate, it does do a pretty decent job of showing equivalency across all four of these major U.S. networks.

FLATOW: And what slows down - you know, you talked about different reception in different cities. Is it the physical structures in the city, or is it the density of cell phones? Because I know when I go to a baseball game, the beginning of the game, there's no one in the stadium, I have no trouble with my phone. As it fills up, it's gone.

Mr. ZIEGLER: Yeah, no, I'll give you a perfect example, a famous example. For the past I think it's three years at CES, you know, you have this crush of technology reporters all filtering into Vegas at the same time, and by, you know, the middle of day one of the show, your iPhones don't work because, you know, everyone has an iPhone, and the AT&T network, it's just crushed.

And to be fair, they do try to do a good job. They have these trucks called cows that are basically portable cell towers that they bring in and station around the grounds to try and alleviate the congestion. But they can only do so much. So you end up having a lot of trouble there.

So population density is a factor, and then also, like you mentioned, physical structures, that's a problem too. In big cities, that's a huge problem.

FLATOW: Are the phone companies spending money on building the 4G network now?

Mr. ZIEGLER: They are, yes. They're spending billions. And actually, to a point you made earlier, that's another reason why these networks tend to evolve a little slower in the States than they do elsewhere because you're talking about, you know, a $10-billion-plus investment per carrier just to roll out these networks.

Because of the size of the country and the amount of data that they need to support here, it's just immense.

FLATOW: Do you recommend early adopting or just a month, six months, things will settle out a little bit more, and choices might be more clear?

Mr. ZIEGLER: Yeah, I think that 2011 is going to be a real watershed year for these networks. And I think that by the end of this year, we're going to see a lot of really cool things shake out.

I'll give you an example. Verizon, as of right now, even though they do technically have 4G LTE launched, they only have two - the only devices they have for it are two modems that plug into your laptop, and neither one of them works with a Mac.

So it's very limited appeal right now, very limited functionality. The devices are big compared to a 3G modem, and those will miniaturize over time. And of course, we'll see a number of phones start to support it over the course of the year.

FLATOW: All right, Chris Ziegler, thanks for your help.

Mr. ZIEGLER: Thank you.

FLATOW: And Chris Ziegler is senior mobile editor at Engadget in Chicago, telling us how to survive. You know, it's always six months, wait another six months for another gadget.

We're going to take a break and come back and test your carbon IQ and a new program to map carbon dioxide and methane emissions right back to their sources. We can trace them and find out why after this break. So stay with us.

I'm Ira Flatow. This is SCIENCE FRIDAY from NPR.

Copyright © 2011 NPR. All rights reserved. Visit our website terms of use and permissions pages at www.npr.org for further information.

NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.