What is 5G? The next-generation network explained

It’s been nearly a decade in the making, but 5G is finally becoming a reality. Carriers started rolling out fixed 5G to select cities a few years ago, and mobile 5G has already made appearances in cities around the country.

Yet, it may seem as though there are more questions about 5G than there are answers. Some wonder where 5G is available, and if they’ll ever see it in their city, while others are more interested in which 5G smartphone they should buy (here are a few ideas). And of course, there is the debate about which carrier will have the best 5G service.

You have questions, we have answers. Here’s everything you need to know about 5G.

What is 5G?

Before we explain how 5G works, it’s probably a good idea to explain what 5G actually is. There are a lot of specifics, which we talk about later in this post, but here’s a quick primer.

Simply put, 5G is the next generation of mobile broadband that will eventually replace, or at least augment, your 4G LTE connection. With 5G, you’ll see exponentially faster download and upload speeds. Latency, or the time it takes devices to communicate with wireless networks, will also drastically decrease.

How does 5G work?

Now that we know what 5G is, it’s a good idea to understand how it works, since it’s different from traditional 4G LTE. First, let’s talk spectrum.

GSMA / ITU

Just like 4G LTE, 5G operates on a wide range of radio spectrum allotments, but is capable of running on a wider range than current networks. The most common form of 5G being used is Sub-6, and there is also mmWave.

Sub-6 refers to 5G that operates at a frequency below 6GHz. All carriers have some form of Sub-6 network, primarily because 4G LTE currently runs on these lower frequencies. For example, T-Mobile has its low-band 600MHz spectrum and its previously Sprint-owned 2.5GHz both in use for 5G.

Sub-6 spectrum is incredibly important in the rollout of 5G, because of the fact that these lower frequency radio waves can travel long distances and penetrate walls and obstacles. That means that carriers can deploy much larger networks without having to build hundreds of cells in every city.

Then there’s mmWave (millimeter-wave), which refers to the ultra-high-frequency radio waves, between 30Ghz and 300Ghz, that are used to supercharge 5G connections and deliver download speeds of multiple gigabits per second. Early on, Verizon relied exclusively on mmWave for its 5G network, though the carrier has now started deploying Sub-6 networks too. While mmWave connections can deliver superfast download speeds, the high-frequency radio waves can’t travel long distances and can’t really get through obstacles — for the most part, even a window or leaves of a tree can block the connection.

That means to make a robust mmWave network, carriers need hundreds, or thousands, of small network cells in every city. Essentially, mmWave network deployment often comes down to having to build little networks around every corner of a building. So why bother? Well, mmWave can handle an incredible amount of data, and an incredible number of users simultaneously. That makes it better for densely populated cities, as well as places like stadiums and arenas.

All of the major carriers are deploying mmWave networks, but to date, those superfast connections are limited to a few downtown areas in major cities. It’s expected that mmWave networks will get more robust, but only time will tell how long that actually takes.

How fast is 5G?

The standards for telecommunications technologies, developed by 3GPP, are somewhat complex, but here’s a general rundown:

  • Peak data rate: 5G will offer significantly faster data speeds. Peak data rates can hit 20Gbps downlink and 10Gbps uplink per mobile base station. Mind you, that’s not the speed you’d experience with 5G (unless you have a dedicated connection) — it’s the speed shared by all users on the cell.
  • Real-world speeds: While the peak data rates for 5G sound pretty impressive, actual speeds won’t be the same. The spec calls for user download speeds of 100Mbps and upload speeds of 50Mbps.
  • Latency: Latency, the time it takes data to travel from one point to another, should be at 4 milliseconds in ideal circumstances, and at 1 millisecond for use cases that demand the utmost speed. Think self-driving car-collision systems.
  • Efficiency: Radio interfaces should be energy efficient when in use, and drop into low-energy mode when not in use. Ideally, a radio should be able to switch into a low-energy state within 10 milliseconds when no longer in use.
  • Spectral efficiency: Spectral efficiency is “the optimized use of spectrum or bandwidth so that the maximum amount of data can be transmitted with the fewest transmission errors.” It’s expected that 5G should have a slightly improved spectral efficiency over LTE, coming in at 30bits/Hz downlink, and 15 bits/Hz uplink.
  • Mobility: With 5G, base stations should support movement from 0 to 310 mph. This means the base station should work across a range of antenna movements — even on a high-speed train. While it’s easily done on LTE networks, such mobility can be a challenge on new mmWave networks.
  • Connection density: 5G should be able to support many more connected devices than 4G LTE. The standard states 5G should be able to support 1 million connected devices per square kilometer. That’s a huge number, which takes into account the slew of devices that will power the Internet of Things (IoT).

In the real world, actual 5G speeds will widely vary. Eventually, Sub-6 networks should be able to deliver speeds of multiple hundreds of gigabits per second, but for now connections can be anywhere from 50Mbps to 400Mbps.

Real-world mmWave speeds are a little harder to pin down, since mmWave isn’t scarcely available in the real world. If you do happen to find yourself on a mmWave network, you may be able to achieve speeds of up to 4Gbps. That’s many times faster than the fastest 4G LTE networks, but again, those connections are sparse, and widespread availability of them is a long way off.

In many areas, 5G is just as fast, or sometimes slower, than 4G LTE. That’s usually due to limited spectrum availability, as carriers try to use one chunk of radio waves to support current 4G networks and new 5G networks simultaneously. Those 5G speeds should improve as more devices are moved over to 5G and carriers start to change the allocation.

What can 5G do?

Improve home broadband

Whikle 5G is commonly thought of in terms of mobile access, it could also have a significant impact on home broadband. Carriers are likely to roll out home broadband services that rely on 5G connections instead of cable or fiber, and Verizon has already started rolling out a 5G Home service. If this becomes more widespread, it could have a significant impact on the likes of Comcast and Charter, which rely on other technologies to deliver home internet connections.

Autonomous vehicles

Expect to see autonomous vehicles rise at the same rate that 5G is deployed across the U.S. In the future, your vehicle will communicate with other vehicles on the road, providing information to them about road conditions, and offer performance information to drivers and automakers. If a car brakes quickly up ahead, yours may learn about it immediately and preemptively brake as well, preventing a collision. This kind of vehicle-to-vehicle communication could ultimately save thousands of lives.

Public safety and infrastructure

Eventually, 5G will allow cities and other municipalities to operate more efficiently. Utility companies will be able to easily track usage remotely, sensors can notify public works departments when drains flood or streetlights go out, and municipalities will be able to quickly and inexpensively install surveillance cameras.

Remote device control

Since 5G has remarkably low latency, remote control of heavy machinery will become a reality. While the primary aim is to reduce risk in hazardous environments, it will also allow technicians with specialized skills to control machinery from anywhere in the world.

Health care

The ultra-reliable low-latency communications (URLLC) component of 5G could fundamentally change health care. Since URLLC reduces 5G latency even further than what you’ll see with enhanced mobile broadband, a world of new possibilities opens up. Expect to see improvements in telemedicine, remote recovery, and physical therapy via augmented reality, precision surgery, and even remote surgery in the coming years.

Remember massive Machine-Type Communications? Well, mMTC will also play a key role in health care. Hospitals can create massive sensor networks to monitor patients, physicians can prescribe smart pills to track compliance, and insurers can even monitor subscribers to determine appropriate treatments and processes.

IoT

One of the most exciting and crucial aspects of 5G is its effect on the Internet of Things. While we currently have sensors that can communicate with each other, they tend to require a lot of resources and are quickly depleting LTE data capacity.

With 5G speeds and low latencies, the IoT will be powered by communications among sensors and smart devices (here’s mMTC again). Compared to current smart devices on the market, mMTC devices will require fewer resources, since huge numbers of these devices can connect to a single base station, making them much more efficient.

Where is 5G now?

So, when should you expect to see 5G in your neighborhood? Well, it you live in a relatively populated area, at least one of the major carriers likely already offers 5G. T-Mobile, AT&T, and Verizon have all rolled out their so-called “nationwide” networks, using Sub-6 5G.

All of the major U.S. carriers are working furiously to build out 5G networks, yet deployment across the entire country will nonetheless take several years. If you’re interested in seeing if your city has access to 5G, check out our 5G coverage guide.

It’s also worth noting that each carrier has a different 5G rollout strategy. This means your 5G experience may vary greatly depending on your carrier. Here are all the details we currently have concerning each carrier’s deployment plans.

Verizon

Verizon offers a smaller 5G network than the likes of AT&T and T-Mobile, thanks largely to the fact that Verizon spent years building out its mmWave network before it started work on Sub-6 technology. That also means that Verizon offers a large number of mmWave small cells — though still not enough to provide a meaningful, reliable mmWave network that’s widespread.

Verizon 5G coverage map

AT&T

AT&T was in the running as the first to offer any kind of 5G in the U.S., but like Verizon, it relied heavily on mmWave in the early days — and as such its recently launched nationwide network is a little smaller than T-Mobile’s. Still, it is large enough to be considered “nationwide,” and the carrier will be expanding its network over time. Its mmWave network has generally been limited to business users and testing, and isn’t as widely available as Verizon’s.

It’s important to note that AT&T really wants you to think you’re always on 5G. If you don’t have a 5G-compatible phone, you may still get a little icon saying that you’re on “5GE,” but that’s not really 5G at all — it’s just AT&T’s new marketing name for 4G.

AT&T 5G coverage map

T-Mobile

T-Mobile took a more measured approach than the other carriers, relying heavily on Sub-6 for its rollout of 5G. The result? T-Mobile’s 5G network is the largest right now. The carrier has been using its existing 4G towers to also deploy 5G, so the coverage is almost identical in most areas. T-Mobile has also launched mmWave in a small number of neighborhoods in specific cities, but it’s very much still in the development stages.

T-Mobile 5G coverage map

What 5G phones are available, and should you buy one?

Although 5G will undoubtedly change the way we interact with each other and consume media, the change won’t happen overnight. It will be a few years before 5G is up and running smoothly across the U.S. in a way that you should care about. Because of that, we don’t recommend buying a phone because it has 5G. Rather, if you like a phone for other reasons, and it happens to support 5G, then it will be an added bonus.

For more, check out our guides on every 5G phone announced so far, and all the best 5G phones you can buy right now.

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