5G: 5th Generation
The G in 5G means it's a generation of wireless technology. While most generations have technically been defined by their data transmission speeds, each has also been marked by a break in encoding methods, or "air interfaces," which make it incompatible with the previous generation.
5G brings three new aspects to the table: greater speed (to move more data), lower latency (to be more responsive), and the ability to connect a lot more devices at once (for sensors and smart devices).
How 5G Works
Like other cellular networks, 5G networks use a system of cell sites that divide their territory into sectors and send encoded data through radio waves. Each cell site must be connected to a network backbone, whether through a wired or wireless backhaul connection.
5G networks will use a type of encoding called OFDM, which is similar to the encoding that 4G LTE uses. The air interface will be designed for much lower latency and greater flexibility than LTE, though.
The standard will work all the way from low frequencies to high, but it gets the most benefit over 4G at higher frequencies. 5G may also transmit data over the unlicensed frequencies currently used for Wi-Fi, without conflicting with existing Wi-Fi networks. That's similar to a technology that all the carriers except Sprint are currently launching, called LAA.
5G networks are much more likely to be networks of small cells, even down to the size of home routers, than to be huge towers radiating great distances. Some of that is because of the nature of the frequencies used, but a lot of that is to expand network capacity. The more cells you have, the more data you can get into the network.
So 5G networks need to be much smarter than previous systems, as they're juggling many more, smaller cells that can change size and shape. But even with existing macro cells, Qualcomm says 5G will be able to boost capacity by four times over current systems by leveraging wider bandwidths and advanced antenna technologies.
The goal is to have far higher speeds available, and far higher capacity per sector, at far lower latency than 4G. The standards bodies involved are aiming at 20Gbps speeds and 1ms latency, at which point very interesting things begin to happen.
What's 5G For?
So Verizon wants to initially use 5G as a home internet service, and everybody else is more focused on faster smartphones. Those uses are table stakes, just to get the networks built so more interesting applications can develop in the future.
A 5G development center in Oulu, Finland, hosted a hackathon convention where the top ideas included a game streaming service; a way to do stroke rehab through VR; smart bandages that track your healing; and a way for parents to interact with babies who are stuck in incubators. All of these ideas need either the high bandwidth, low latency, or low-power-low-cost aspects of 5G.
This year, we surveyed the 5G startups that Verizon is nurturing in New York. At the carrier's Open Innovation Lab, we saw high-resolution wireless surveillance cameras, game streaming, and virtual reality physical therapy.
Driverless cars may need 5G to really kick into action, Oliver Rist a editor at PCMag explained after The International Consumer Electronics Show this year. The first generation of driverless cars will be self-contained, but future generations will interact with other cars and smart roads to improve safety and manage traffic. Basically, everything on the road will be talking to everything else.
To do this, you need extremely low latencies. While the cars are all exchanging very small packets of information, they need to do so almost instantly. That's where 5G's sub-one-millisecond latency comes into play, when a packet of data shoots directly between two cars, or bounces from a car to a small cell on a lamppost to another car. (One light-millisecond is about 186 miles, so most of that 1ms latency is still processing time.)
Another aspect of 5G is that it will connect many more devices. Right now, 4G modules are expensive, power-consuming, and demand complicated service plans, so much of the Internet of Things has stuck with Wi-Fi and other home technologies for consumers, or 2G for businesses. 5G networks will accept small, inexpensive, low-power devices, so it'll connect a lot of smaller objects and different kinds of ambient sensors to the internet.
What about phones? The biggest change 5G may bring is in virtual and augmented reality. As phones transform into devices meant to be used with VR headsets, the very low latency and consistent speeds of 5G will give you an internet-augmented world, if and when you want it. The small cell aspects of 5G may also help with in-building coverage, as it encourages every home router to become a cell site.
We're looking forward to testing the first implementations of 5G as soon as they are live.