If you've been watching the news lately, you've probably heard of 5G technology and how it is set to transform our lives. As the next-generation cellular data network, it is expected to radically improve wireless connections and data transfer rates, and power some of the most advanced data technologies like smart cities, autonomous vehicles, and more.
What does 5G mean though? How does it work? Is it safe? And how fast are 5G connection speeds expected to be?
What is 5G?
The term 5G refers to the fifth generation of cellular data technology. While not a single technology in itself, 5G is a collection of technologies that work together to form a specific technology standard that other devices can connect to for internet access.
According to Qualcomm, a leading mobile technology company, "5G wireless technology is meant to deliver higher multi-Gbps peak data speeds, ultra-low latency, more reliability, massive network capacity, increased availability, and a more uniform user experience to more users. Higher performance and improved efficiency empower new user experiences and connect new industries."
What makes 5G exciting for many is that the data transfer rates for 5G are substantially higher, and so it is expected to enable all sorts of new consumer technologies that simply aren't possible with existing the 4G LTE network infrastructure. The most promising of these is so-called "smart city" infrastructure, like autonomous bus lines, improved traffic monitoring and management, electricity and water system management, and more.
Advantages and Disadvantages of 5G
The biggest advantages of 5G are going to be the number of concurrent connections as well as the data transfer speeds of those connections. The part of the radio spectrum that 5G accesses is almost entirely unused, so there is far less interference from different radio signals that can limit how fast data can be transmitted. What's more, since it's far less congested, you can have many more devices connected to the network that will enjoy the full benefit of a 5G network's improved data speeds.
The biggest downside of 5G networks is that you will need special equipment to access them. Old phones and tablets won't be able to connect to 5G networks, and any existing connected infrastructure will need to be upgraded in order to work with 5G. These upgrades aren't too onerous when it comes to your phone or other mobile devices, but they can be quite costly when you're talking about upgrading city infrastructure.
More recently, airlines in the United States protested that 5G masts near airports threatened to interfere with critical equipment in airplanes like altimeters that rely on radio signals near the frequencies that new 5G networks use. This can be potentially hazardous when a plane is attempting to land, especially in bad weather, when the altimeter is important for knowing how close the plane is to the ground. As a result, network providers are restricting their networks around airports and are looking for other solutions to the issue.
How Does 5G Work?
5G is a cellular network, which means it operates using a system of cell sites that carve each area up into different sectors and transmit encoded data through radio waves. Each of these sites needs to be connected to a network "backbone", most often a physical wired connection, and the encoding they use is different depending on the type of network.
In terms of infrastructure, there isn't all that much different about 5G compared to existing cell sites, but the new 5G networks will enable those cell sites to access a much wider band of frequencies than before. 5G networks use OFDM encoding, which is similar to the type used in a 4G LTE network but provides an "air interface" with lower latency and access to more airwaves than 4G LTE.
The biggest feature of 5G is that cell sites will have access to short-range, "high-band" airwaves that were inaccessible with 4G LTE technology. Moreover, 5G lets devices use wider channels across a larger chunk of the radio frequency spectrum. Regulators and carriers have to unlock those channels for customers to use, which is only now just starting to happen. But as those channels become accessible speeds are set to increase dramatically.
On old 4G LTE networks, a device can combine up to seven, 20 MHz channels, or 140 MHz of total spectrum usage, though phones typically fall short of that (around 60 MHz or less). Low and mid-band 5G lets a device combine up to three, 100 MHz channels with several 20 MHz channels from the 4G LTE network to considerably improve network speeds, but it's hardly the "fourth industrial revolution" that we've been promised for several years now. The real game-changer is the millimeter wave ("mmWave") (24-39 GHz) short-range radio signal known as high-band 5G, which lets you stack up to eight, 100 MHz channels to vastly improve data transfer speeds and latency.
Cellular carriers are also able to stitch together 4G and low-band 5G frequencies using something called dynamic spectrum sharing, based on network traffic, to get the most out of their existing 4G network. But this is mostly just an improvement to the current 4G network, rather than something genuinely new, and so you don't see the significantly faster data rates of true 5G networks. This hasn't stopped some network carriers from marketing these slight improvements to 4G LTE networks as 5G or similar, which has led some to mistake these for actual 5G networks. And since these networks aren't much faster than 4G LTE, this has left many with the impression that 5G isn't that big of a deal. These aren't real 5G networks, though, at least not what anyone meant when they were talking about 5G for the past few years. What everyone really means is high-band 5G, which is starting to roll out in earnest in the US and elsewhere in 2022, so perceptions of these networks are sure to change rather quickly.
Who Invented 5G?
Neither an individual nor a company invented 5G technology. Several companies in the mobile technology space came together to develop the new 5G wireless network standards to help streamline the technology so that all companies and customers could benefit from the same technology. Some of the leading companies involved in building the network equipment are Qualcomm, Huawei, Samsung, and Ericsson. Mobile providers from around the world have also been involved regionally to set up network towers and build up the physical infrastructure that will make up the 5G network.
How Fast is 5G?
The 5G technology standard calls for significantly faster speeds than existing 4G LTE network technologies. At its theoretical peak, 5G has a maximum download speed of 10 Gbps with a latency as low as one millisecond. Of course, these data speeds won't be available for many years; and even then, it will depend on network coverage and specific circumstances. But a base speed of 50 Mbps should be the absolute floor of what is available, while we should eventually see speeds that are more than 100 times faster than average 4G network speeds. The fastest speeds though will come from the mmWave high-band signals, but since these signals are fairly weak and have a rather short range, these will likely be reserved for special pockets of coverage that require these faster speeds.
Is 5G Safe?
There are two answers to this question, depending on what you mean by safe. If you mean safe for humans, then yes, 5G is safe. Most 5G signals use the same kind of radio waves that TV and radio networks have been using for many decades now, as well as those that cellular and Wi-Fi networks have long been using without issue.
The genuinely new technology in 5G, the millimeter frequency signals of the mmWave technology, are technically microwaves, which are naturally going to be misunderstood by a lot of people. These signals are very weak, don't travel very far, and aren't even able to penetrate the leaves on nearby trees, much less the walls of your home. Old fashioned UHF television signals are much more powerful than anything 5G towers are putting out, but those signals have been in use since the 1960s and are very heavily congested as a result. The radio waves from mmWave transmitters aren't going to cook people's brains. Even if you were to stand next to a transmitter, the signals aren't even strong enough to get past your skin. There are also clear safety guidelines for this. For example, The International Commission on Non-Ionizing Radiation Protection (ICNIRP) is a global scientific body that has determined a norm for the non-ionizing radiation put out by mobile phones and telecom antennas and continually monitors their thermal effects.
The value of 5G mmWave high-band signals isn't that they are somehow much more powerful than the radio signals we've been using before, but precisely because no one uses these frequencies, and so there isn't anything clogging up the airwaves. That hasn't stopped people from turning 5G into conspiracy theory fodder, though. Now, if we are talking about whether 5G signals can interfere with other radio signals in an unsafe way, that is a very different issue. Like all radio signals, they are subject to interference and are capable of interfering with other radio signals.
The two most serious issues are with radar equipment used in many airplanes and with certain weather monitoring satellites. In the case of weather satellites, 24 GHz frequency signals used by 5G networks can "leak" into the nearby 23.8 GHz frequency band used by weather satellites to monitor atmospheric moisture. This monitoring is critical to proper weather forecasting, and there is concern that 5G networks can reduce the accuracy of weather forecasts by as much as 30%. This would be the equivalent of setting back weather forecasting accuracy by several decades, leading to lower preparation response times to major storms like hurricanes.
Is 5G Really a Threat to Airlines?
The other major concern about 5G interference is with radar altimeters used by airplanes to measure their altitude, something we can all agree is important for everyone's safety. Recently, airlines in the US have protested that 5G emissions in the 3.7 GHz to 3.98 GHz C-band frequency risk interfering with the proper functioning of an airplane's altimeter, which uses radio frequencies between 4.2 GHz to 4.4 GHz. Verizon and AT&T, who spent billions of dollars to buy the rights to use frequencies in the 3.7 to 3.98 GHz spectrum, have pushed back on these fears, saying that there is more than adequate space between their 5G signals and those used by radar altimeters. They also expressed frustration with regulators who they say raised concerns at the last minute despite having two years to prepare for the introduction of 5G around airports.
"At our sole discretion, we have voluntarily agreed to temporarily defer turning on a limited number of towers around certain airport runways as we continue to work with the aviation industry and the FAA to provide further information about our 5G deployment, since they have not utilized the two years they’ve had to responsibly plan for this deployment," AT&T said in a statement on January 18, 2022.
Clearly, there is still some friction between aviation and telecommunication industry giants, with government regulators working to navigate the two competing interests to find a workable solution. This came to a head recently, when in January 2022, a number of airlines, including British Airways, Emirates, and Air India, canceled or changed US-bound flights over concerns about the deployment of 5G technology near airports. The Federal Aviation Authority has also begun updating its guidance on which airports and aircraft models will be affected by 5G and AT&T and Verizon announced they will temporarily pause the 5G rollout near key airports.
Of all the concerns around 5G, the issues of weather satellites and aircraft altimeters are clearly legitimate and are actively being addressed between the various parties. How these will ultimately end up is still an open question, though, given the safety issues involved, it is likely that the 5G network providers will have to give ground in the end.
When Will 5G Roll Out?
It's been a long time in coming and after two years of delay, major 5G networks are starting to be activated in major cities around the world. While it will still take time for the networks to mature and for coverage to expand to more rural areas, the process has begun and 5G might finally start to deliver on its lofty promises of transformational speeds and technological advances.
What those advances will be is hard to predict. When 2G rolled out in the 1990s, everyone thought that digital voice calling was going to be the big advance of the era, but it was SMS text messaging that actually came to define that generation of technology. With 3G, mobile internet service was expected to be the "killer app" of the generation, but it turned out to be social media and smartphone apps. Likewise, 4G LTE saw the introduction of a whole new catalog of apps like ride-sharing services, food delivery, and services powered by cloud computing, but streaming services like YouTube, Netflix, and video calling services like FaceTime made 4G LTE all about video content. Given the potential for 5G, there is no way of knowing what that next step up in technology will end up being, but at long last, we're finally on our way to finding out what it will be and it's about time.