We hear a lot about Bluetooth and some of us even use it religiously on a daily basis. It’s helpful for a handful of things — wireless headphones, a wireless mouse, mobile hotspots, and so, so much more. But, how does Bluetooth work exactly? How does it create the signal/connection for device-to-device interaction? We’re going to walk you through that and dive a little bit more into the technology below.

What is Bluetooth?

Bluetooth is, in its most basic form, a short-range communication that uses radio waves to connect between mobile phones, computers and many other electronics (wireless speakers, wireless headphones, and so much more). For example, you could use Bluetooth to connect a wireless speaker to your phone so that you can play music on your phone and output it through the wireless speaker. Or, it could be that you have a Bluetooth headset connected up to your phone so you can wirelessly make calls while on the road.

How does Bluetooth work?

Bluetooth is a very small area network that transmits data through low-power radio waves. It does this on the 2.45GHz frequency band. If you’re familiar with that band at all, you’ll know that it’s solely been put to use, by international agreement, for industrial, scientific and medical devices (ISM). That said, Bluetooth has to operate in a way that it does not interrupt or interfere with these devices.

To avoid interference, Bluetooth sends out very weak signals — 1 milliwatt, actually. Despite such a weak signal, the walls in your house aren’t going to interfere with it, so you should be able to connect to multiple Bluetooth devices in multiple rooms with no problem.

Believe it or not, Bluetooth can connect up to 8 devices simultaneously without interfering with each other. Bluetooth takes advantage of a technology called spread-spectrum frequency hopping. This technology ensures — or at least makes it a rare possibility — that two devices are communicating on the same frequency at once. Because of spread-spectrum frequency hopping, a Bluetooth device will use 79 randomly chosen frequencies, changing from one frequency to another regularly. When it comes to Bluetooth, transmitters actually swap frequencies 1,600 times every second.

Bluetooth is nice because of how hands-free it is. It requires almost no interaction on the user’s end. When you come into contact with a Bluetooth device, an automatic electronic conversation takes place. This “electronic conversation” determines whether a device is sharing information or whether a device needs to control another. For example, a wireless speaker would share information with your smartphone, and your smartphone would control the wireless speaker.

During this process, the devices form what’s called a personal-area-network or piconet. Once this network is established, the Bluetooth devices actively change frequencies in order to avoid interfering with another Bluetooth device — basically, what we were talking about with the spread-spectrum frequency hopping earlier.

What about Bluetooth 5?

Bluetooth 5.0 is still, well, Bluetooth, but with some neat improvements for standard usage, but primarily for up and coming smart home gadgets or Internet of Things (IoT) devices.

Here’s the rundown directly from Bluetooth SIG:

“Key feature updates include four times range, two times speed, and eight times broadcast message capacity. Longer range powers whole home and building coverage, for more robust and reliable connections. Higher speed enables more responsive, high-performance devices. Increased broadcast message size increases the data sent for improved and more context relevant solutions.”

Bluetooth 5 might be aimed to IoT devices, but with it, Bluetooth 5-equipped devices bring 4x the range, 2x the speed and 8x the broadcasting message capacity. It’s quite an improvement.


And that, in a nutshell, is how Bluetooth works! It’s an extremely interesting technology that’s getting better and better after every iteration or new release. Wireless technology is without a doubt the future of tech. Even right now, it makes it so easy to go cordless. As far as audio goes, some might complain, but it’s getting better as people develop ways for their hardware to interact with wireless technologies (i.e. the Apple AirPods).

We’ll only see Bluetooth improve as time goes on. The Bluetooth Special Interest Group (Bluetooth SIG) is constantly improving things and making them better. In fact, the recent release of Bluetooth 5 has given Bluetooth improvements of 4x the range, 2x the speed and even 8x the broadcasting message capacity, ultimately making Bluetooth operate better with many devices, but especially smart home technologies like the Internet of Things.

Bluetooth will only get better and better.