Nowadays we expect to have high-speed internet access wherever we go — and for the most part we do. But as more and more of us go online, and as we use more data-hungry apps, what happens to all of those signals in the air?
The wireless spectrum is not infinite and there is a lot of competition for bandwidth. Radio, television, emergency services, aeronautics, satellite communication, and cellular telephone networks all have to be allocated their space.
Too many signals in the same space on the same frequency and things can quickly go awry.
What Is Wi-Fi Spectrum Crunch?
As the number of active cellphones grows, cellular networks need more bandwidth to accommodate it all. And as more and more people use smartphones, accessing huge amounts of data all the time, it only gets worse. In certain circumstances, there simply isn’t enough bandwidth to go around — and everybody suffers.
This is what we call spectrum crunch, and it doesn’t just affect cellular networks. It’s happening to Wi-Fi networks all over the world.
Think of it like a traffic jam. Highways handle large amounts of fast-moving traffic, but if the roads ever reach capacity, everything slows to a crawl. Similarly, an over-capacity wireless network results in slower data transfer speeds for everyone.
When cellular networks get clogged up, providers can offset this to some extent with higher data costs and sometimes even data capping. But these efforts push people to cut down on data usage and to start using public Wi-Fi instead. And that’s great news for cellular providers because it lessens their strain, but causes more stress for those Wi-Fi networks.
Indeed, when the air is full of too many Wi-Fi connections, those waves can clash and interfere with one another. When you’re in a crowded venue or location (e.g. colleges, stadiums, conference centers, apartments, etc) and everyone’s trying to use the same Wi-Fi, the signals create a wireless traffic jam.
But as long as you have a big fat data cable with a really fast connection, you can keep adding wireless access points to counteract the congestion, right?
The more access points you have, the more interference each connection is subject to. The spectrum allocated to Wi-Fi is limited, and if too many people are connecting and sending data, the speed of the service rapidly deteriorates. The problem is compounded by devices that constantly attempt to switch frequencies.
In other words, the slowdown has nothing to do with the absolute speed of the actual network and more to do with the number of signals. Think of it like this: raising the speed limit does nothing to help a congested highway, but removing cars would definitely help.
Is There a Solution to This Mess?
Luckily, there might be soon.
Researchers at MIT have come up with a technology that improves the way routers work together, reducing interference and increasing available bandwidth, which ultimately means faster speeds in crowded areas.
According to the researchers, this proposed system (called MegaMIMO 2.0) will triple the bandwidth and double the range of a modern Wi-Fi signal. This development is a follow-up and improvement on MegaMIMO 1.0, which was another MIT breakthrough that happened back in 2012.
MIMO stands for Multiple Inputs, Multiple Outputs and describes the technology for using multiple transmitters and receivers to transfer more data at the same time. All wireless products using the 802.11n standard support MIMO.
MegaMIMO 1.0 coordinates multiple transmitters so they don’t interfere with each other, but it requires users to actively share data about their movements. MegaMIMO 2.0 requires no action on the user side, and so is easier to implement. It allows multiple transmitters to transmit on the same spectrum without interfering with each other by synchronizing their phases.
The video below explains how it’s done and the full paper is available if you want to know all of the technical details:
The researchers believe the same principle could be used to reduce spectrum crunch on cellular networks, not just on Wi-Fi networks, which would be great news for all of us.
MegaMIMO requires hardware and software changes across the board, so it will likely be a few years before we start reaping the benefits, but the technology itself isn’t expensive so we could be seeing it as early as in the next generation of wireless devices, assuming commercial versions can be produced quickly.
But I Want Less Congestion Now!
What can we do to reduce the effects of spectrum crunch and reclaim our full Wi-Fi speeds in crowded areas? There are a few things you can try:
- If you’re on public Wi-Fi, avoid using high-bandwidth applications such as Netflix, YouTube, and Spotify. You’ll struggle to use them if it’s busy, and even if you’re successful you’ll make the problem worse for everyone else. (Some public Wi-Fi hotspots block high-bandwith apps anyway.) If you’re setting up your own Wi-Fi hotspot, consider blocking these services.
- Change Wi-Fi networks if another one is available, particularly to a 5 GHz one. 5 GHz has a shorter range than the more common 2.4 GHz, but has higher bandwidth. Both of these features make it less likely to experience spectrum crunch.
- Be prepared. If you know you’re going to be relying on public Wi-Fi, download what data you can before you go out. For example, you might want to download podcasts, audiobooks, or music to listen to offline — even consider downloading Google maps if you’ll be in an unfamiliar area.
- If you find the Wi-Fi slow but really need internet access, try switching to cellular data (but keep an eye on your usage.)
- If possible, get away from the crowds. There may be a spot close to an access point that’s not too busy.
Do you often run into congestion problems on public Wi-Fi? Do you have any workarounds? Please let us know in the comments section below.