Wireless data is a complex subject, isn’t it. From 2G through 5G, early GSM to later CDMA, it’s a salad of creations and concepts. There’s even a bit of Hollywood sparkle. (Did you know the spread-spectrum concept that underpins many wireless technologies was invented by actress Hedy Lamarr, one of many female inventors in the history of telecoms?)
But fast-moving technologies create questions. Why is LTE/5G so promising? What are its benefits? And how can it work at sites far from “covered” areas? Addressing these concerns is the point of this article. Show it to curious colleagues as an easy help sheet. And for a more in-depth look at these topics, download our recent paper, “The 5G for Business Guidebook”.
Bandwidth’s unifying theme: frequency
To understand why LTE/5G holds so much promise – and is already delivering for Blue Wireless’ 300+ customers – it’s useful to have a unifying theme. An idea that helps us see the wireless communications world as a whole. That idea is rising frequency.
A reminder for those long out of High School. Electromagnetism travels in waves; frequency is how many waves pass by a set point in a set time. The more waves (measured in Hertz, cycles per second), the higher the frequency. And the higher the frequency, the more data you can pack onto it, and the more bandwidth the customer can enjoy.
That’s the story of wireless data communications: ever-rising frequencies enabling ever-higher bandwidth. Easy, isn’t it?
Frequency up, range down
The downside is range. A whale’s wailing can be heard around the world (if you’re another whale) because its frequency is very, very low: just a few Hz. But radio waves (including all wireless data today) are much higher: 1KHz to 100GHz. Which means they find it harder to penetrate the medium they travel in (air).
Early 2G data plans couldn’t carry much more than an email, but 2G frequencies—800-1900 million hertz, or MHz—meant even cell towers 50km apart could keep you connected. 3G and 4G’s range was less than half that, as frequencies rose into the gigahertz bands. 5G reaches higher still, with plans for 50GHz+ on the tech pathway—but because of this, cell towers and other nodes have to be less than 300m apart, tops. You can’t break the laws of physics.
Side note: this 50GHz figure, incidentally, is why 5G scare stories are Fake News. Ionising radiation (the dangerous kind) starts way into the ultraviolet part of the spectrum, with frequencies in the Terahertz (THz) range—thousands of times higher than anything planned for 5G. Take that, Fake Newsmongers! (Also, this is why you shouldn’t spend too long on a tanning bed.)
Limited range, but amazing bandwidth
The upside to this limited range is that 5G technologies have the potential for incredible bandwidth. Combined with other telecoms wizardry, 4Gb/s is on the horizon—enough for several hundred people to all watch Netflix at once. That’s what high frequencies enable.
(Since they’re so useful, you might ask why network providers didn’t just start with higher frequencies, years ago. The answer is basic economics. Higher frequencies need more densely-packed cell towers; in the early days, the real estate just wasn’t available at the right price. Simple things like getting permission to install a tower on a rooftop can take years.)
For a remote site, high-bandwidth wireless is a technician’s dream. No need to lay cables between your buildings. No need to negotiate rights-of-way across roads and geographical features. And with far higher bandwidth, complex factories with thousands of moving machines can all be connected up in the Internet of Things, and the data they produce, mined for business improvement insights.
But if you want to connect to the rest of the world—such as a global SD-WAN—you still need to connect to other networks. And that’s where LTE/5G comes in.