Tech Explained: 5G

5G promises to make mobile connectivity vastly faster, so how does it work and what is the price to pay for increased convenience in the IoT network?

By now, almost everyone with a mobile device has heard of 3G and 4G. Soon, however, a new protocol called 5G will be rolled out. These fifth-generation mobile networks will be much faster than previous generations and are poised to open up new uses for mobile data. So, what is 5G, and what advantages will it bring?

First-generation networks were analogue, and only carried voice signals. In the 1990s, digital 2G networks were launched which offered basic features like text and picture messaging. By the early 2000s, 3G networks offered speeds fast enough to allow video calling and mobile data. Ten years later, 4G networks were fast enough to support mobile internet, video streaming and gaming.

Beginning in 2019, several countries will begin rolling out 5G. Early adopters will include South Korea, the U.S., Japan, China and the UK. The 5G networks will be much faster than existing 4G – possibly up to 100 times faster, up to 10 GB per second. This is fast enough to download an entire HD movie in just ten seconds. To put this in perspective, the same movie would take more than 24 hours in 3G and around 7 minutes in 4G. The 5G networks will also reduce lag time to milliseconds. Eliminating this latency is key to the development of self-driving vehicles, where a longer delay could be enough to cause accidents. 5G networks will also have greater capacity, to cope with the increasing amount of IoT devices.

A basic mobile network works by converting data, such as your voice or a video, into an electrical signal which is transmitted to the nearest mobile tower along electromagnetic (radio) waves. The signal is passed along through a network of towers, before arriving at its destination (such as another phone).

The frequency of a wave is the number of waves produced by a source, or passing through a certain point, each second. Most radio stations broadcast radio waves with frequencies of about 100MHz, while most wireless networks operate at around 2.6 GHz. The 5G networks, in contrast, will operate in a very high frequency range above 15 GHz. These are also sometimes called millimetre waves. This range of frequencies is much less crowded and can carry more information much faster.

However, the higher frequency bands cannot carry information as far, and have difficulty getting around obstacles such as walls and buildings. This is because, like light, sound and gravity, radio waves follow the inverse square law – every time the distance doubles, the energy is cut in half. This means that 5G will require many more antennas, to boost the signals. Some experts warn about the potential health risks associated with the elevated exposure to electric and magnetic fields (EMFs) in the high-energy range. In 2011 the World Health Organization (WHO) classified radio frequency radiation as a possible 2B carcinogen.

Some estimates suggest that 5G can support up to 1,000 more devices per metre than 4G. This has important consequences for the development of the IoT. The speed and capacity of 5G will allow almost every device to sport a ‘smart’ capability. Aside from autonomous vehicles, 5G could allow remote operation of everything from factories to surgery. We have already seen the promise of the IoT in innovations such as handheld location trackers that work in real time and smart home intercoms that let users open doors remotely.

5G could also allow virtual and augmented reality to operate without any perceptible lag, making them much more practical for a wide number of uses. For example, satellite navigation could be projected onto a car windscreen, or targeted adverts could pop up as people walked by store windows. 5G-enabled smart devices, from electrical grids and smart lighting systems to bins, could also save time and money. In fact, 5G provider Qualcomm estimates that by 2035, 5G will support the production of up to USD 3.5 trillion worth of goods and services.

There are still significant hurdles to overcome. The available spectrum is also not endless. Because of concerns about spectrum running out, the industry must come up with smarter ways to use what is already available.