How 5G works: the pros and cons By The Verge

(upbeat music) - 5G internet. We've been talking about it for a while and now it's finally starting to arrive. It's a revolutionary kind of internet that promises to change everything from your phone, to home internet, to more futuristic fields like self-driving cars and even remote surgery, but 5G's also been in the headlines lately for a lot of bad reasons with bizarre conspiracy theories and rumors. So, to help clear things up, we're gonna explain to you, what exactly 5G is, how we got here, what the technology behind it is, and any real concerns that might exist around the new technology. (chill music) So, what is 5G? Well, 5G or fifth generation, is the next step in mobile internet technology. It's what all of the next wave of phones and tablets are gonna use for speeds that are even faster than the LTE networks that we already have.

Now, our news editor and reviewer, Chris Welch, has actually been testing all these networks for awhile already, so he can actually tell you what it's like to use these speeds today. - Okay, so all the big US carriers are well underway with rolling out 5G, and by the end of this year, you should be able to get it wherever you live in the US, but what 5G means on each carrier is different. Speeds are different, coverage is different, so for the last year I've been testing out all the networks, Verizon, AT&T, T-Mobile, and Sprint is now part of that, just to see how fast it is and what a difference it makes in your day to day life. So let me try and explain. Now Verizon's 5G is blazing fast; you can get download speeds of over one gigabyte per second.

That's up to 10 times faster than most home wifi connections. You can download a whole season of a TV show in just minutes, but the problem is coverage. Verizon's 5G is very, very spotty. It's there on one street and gone the next, and indoor coverage is pretty much nonexistent. That's because Verizon bases its whole 5G plan, for now, on what's called high band millimeter wave technology.

You've seen it in those commercials as ultra wideband 5G. But the issue is, the signal can't travel very far, so in an city where it wants to roll out 5G, Verizon's gotta put up all these nodes all over the city, and that's not really practical to do nationwide, so later on this year, Verizon's also gonna turn on its low-band 5G network, but there the speeds aren't that much faster than what your LTE phone can do today. So for now, Verizon's 5G network isn't really worth upgrading to a new phone for, unless you've got a node like right outside your apartment or your house. T-Mobile has the most comprehensive 5G plan of all the US carriers. It's also using millimeter wave on the high end, plus Sprint's midband spectrum in the middle, and it's own low-band 5G at the base.

Now Sprint's midband spectrum is much faster than LTE is today. I was in Texas testing their 5G network and I got speeds of 300 megabytes per second. And unlike with Verizon, I could count on keeping that 5G signal wherever I went. Think of midband as the sweet spot for 5G. It's much faster than phones today, it's not quite as fast as millimeter wave, but it makes a big difference day to day.

And last is AT&T which has a similar strategy to Verizon, in that you get the high-band millimeter wave and low-band sub six 5G, but they're missing that middle part of the cake, that midband spectrum, so you'll have really fast speeds in small parts of some cities and somewhat faster speeds than your phone today everywhere else. Now none of this is to be confused with AT&T's fake 5G, which is called 5GE. You've probably seen it in your phone's status bar at times. That's just fast LTE. It's got nothing to do with real 5G that's rolling out right now.

These are still the early days of 5G. We've seen less than a dozen phones hit the market that offer these new faster speeds and some of the early ones were very buggy and would overheat in the summer. Now those concerns, along with battery life, have largely been overcome with Qualcomm's latest chips. We've seen those chips in the Galaxy S20, the LG V60, and the OnePlus 8, all really great phones, but we're still waiting for that first iPhone from Apple that has 5G and that's rumored to come later on this fall in 2020. (upbeat music) - So, when we talk about 5G, we're not really talking about anything that's radically different than our current and past mobile technology.

Let's put that in perspective. The earliest generation mobile technology, 1G networks, were launched back in the 80s. Unlike the other generations, 1G networks used analog signals and could really only do voice calls. You've probably seen phones that use 1G networks like the Motorola Dynatac, that classic oversized cell phone from 80s movies.2G networks kicked things up a notch. More bandwidth meant that in addition to calls, users could start sending data, enabling text messages, SMS, and even pictures, MMS.

Later versions of 2G phones could even access basic internet, like the most famous 2G device ever sold, the original iPhone.3G networks offered even more bandwidth and faster speeds, and 4G LTE, which is what most of our current phones use, made truly fast wireless internet a possibility. And 5G, as Chris mentioned earlier, takes things a step beyond even that, with speeds that are faster in some cases than home wifi. But the key thing is that all these technologies aren't fundamentally different. They're all based on the same science, which means that it's time to talk about the electromagnetic spectrum. This is the EM spectrum, the diagram of the different types of electromagnetic radiation that exists.

EM radiation is what we call a wave of photons traveling through space and all EM radiation, be it AM radio waves, X-rays, infrared, or even visible light fall somewhere on the electromagnetic spectrum. The difference between harmful X-ray radiation and benign AM radio, is simply the amount of energy it has. Now, on the right end of the spectrum are low energy radio and microwaves, which are characterized by low frequency and long wave lengths. As we travel up the spectrum, wave lengths get smaller, frequencies get higher, and the amount of energy being transmitted gets higher too. AM radio, for example, broadcasts between 540 and 1600 kilohertz.

It's low energy, but those low wave lengths can travel incredibly far, up to 100 miles. And depending on atmospheric conditions, they can potentially span the globe by bouncing off the atmosphere. But again, quality suffers. - We hear sound originating at that very moment, hundreds, or even thousands of miles away. - Go up the spectrum though, to FM radio which broadcasts at between 88 and 108 megahertz, and you've got more bandwidth, which allows for higher quality broadcasts, but your usable range decreases.

It's the same basic idea with cellular data. New generations allow us to improve our transmission technology, which leads to increased bandwidth and higher frequencies, which in turn leads to faster speeds. But at the core, it's all the same basic technology and the different types of 5G, actually illustrate this really well. For example, take AT&T and T-Mobile's low-band networks which Chris referred to. They're in the 600 megahertz and 850 megahertz bands, effectively the same area of spectrum as existing LTE, but the fact that they're new bands of spectrum that aren't already clogged up with existing customers, combined with new transmission technologies, means that these low-band 5G networks can offer faster speeds than LTE, even though they're basically using the same spectrum bands as LTE.

And that low-band nature, also means that they can transmit over a much wider range than other types of 5G. It's why T-Mobile, for example, can claim to have nationwide 5G coverage, while Verizon is stuck to just a few street corners. Next is midband 5G, which is basically just used by Sprint and now T-Mobile, which owns Sprint. Located at the 2.5 gigahertz range of the spectrum, it offers faster speeds than low-band 5G, but it has more limited range. For comparison, 2.5 gigahertz is about the same area of the electromagnetic spectrum as your home wifi. Now midband is middle of the road in almost every respect.

It's higher frequency and more bandwidth than low-band 5G, but it's not gonna be quite the speeds and frequency that you'll get from millimeter wave, which is the ultra fast 5G. Now these are located around 30 gigahertz, much higher frequency than any other types of 5G and they offer blazing fast speeds; the ones Chris mentioned earlier from Verizon and in limited areas, T-Mobile, and AT&T, but those radio waves are also really small, between one and 10 millimeters, hence the name, which are actually really bad at passing through objects like walls or buildings, which means that the range is incredibly limited. So even though it offers the fastest 5G speeds, it's also the 5G that you'll probably end up using the least, because that rollout, it's just gonna be really small. But those increases in bandwidth are only part of the story. A lot of the improvements in 5G, come from new transmission technology.

Things like carrier aggregation, which combine multiple LTE bands into one data stream for faster speeds, or MIMO antennas, or multiple input multiple output, where we use antenna arrays, made up of lots of little antennas to improve connectivity. (chill music) But is 5G, or really any cellular radiation, safe? Well, there've been a lot of inaccuracies going around about 5G. Some are completely absurd, like the idea that 5G somehow caused the coronavirus, but the simple answer is that 5G is basically the same as any other type of cellular radio technology and we already have a pretty good idea that cellular radiation is not harmful. - Of course people are concerned a little about possible effects of the formation of cancer if you use your mobile phone a lot or if you've been exposed continuously to radiation from cell towers. There's a lot of studies available on that sort of effect, but that's never been proven that indeed there is a carcinogenic effect of expose to radio frequency radiation.

There's also concern that exposure to radio frequency fields, for instance the higher fields, the higher frequencies that 5G's got to use, that that may result in adverse affect on the immune system, and that people may be more susceptible for the, for infection by the COVID-19 virus. There's no proof, no indication whatsoever that there's any effects on the immune system from expose to radio frequency fields. - Now, I know that cellular radiation falls into the non-ionizing portion of the spectrum. Can you talk a little more about the differences between non-ionizing and ionizing radiation? - Ionizing radiation has a very high energy content and because of that, it is possible that if you are exposed to that sort of radiation, that chemical bonds in the body, that they are damaged and broken, and that may result in uncontrolled cell growth, which may result in the formation of cancer. This sort of effect, breakage of chemical bonds, is something that is not possible with non-ionizing radiation, with the type of radiation that cellular technology uses, because the energy content of that type of radiation is not enough to result in such chemical breakage.

The entire spectrum of non-ionizing radiation, up to UV radiation, is something that has no energy content that is high enough to break chemical bonds. Heating is the only proven effect of exposure to radio frequency radiation. (chill music) - While 5G doesn't pose any health risks, there are gonna be practical issues with the transition to 5G. Some of the growing pains are just switching to a new generation of technology. Things like more expensive plans.

That faster data speed means that you can burn through your data cap really quickly, and that's something that we're gonna have to figure out. The first wave of 5G phones were more expensive, although prices are starting to come down. And of course, there's just building out the networks. The low range of midband and millimeter wave networks, means that it'll take longer and cost more to build more towers, to get that kind of coverage that people expect. The good news is, is that we've already started.

Qualcomm, for example, has made 5G the default in all of of its new chips and flagship phones in 2020, from companies like Samsung, Apple, OnePlus, are either already shipping with 5G, or expected to have it by the end of the year. And that's to say nothing of the big advances that carriers like Verizon, T-Mobile, and AT&T have made in building out the actual networks. And more importantly, none of these issues are really new. The transition from 2G to 3G, or from 3G to LTE, saw similar problems and the tech industry was able to solve them. The only difference is that we're a lot more reliant on our phones than we were 10 to 15 years ago, and that's why these issues seem so much more important now.

But the key thing to remember is that 5G and the technologies around it, aren't really new. It's just our perspective on them, and our reliance on our phones that's really changed. Thanks so much for watching. We've been really working on a 5G explainer for a while, so we're really glad to have put this together. If you have any other questions about 5G or technology in general, let us know.

Source : The Verge