18 Bluetooth
Features
Bluetooth technology is a short-range (33 feet / 10 metres) wireless communications technology designed to replace the cables connecting electronic devices. For example, use a wireless headset or earbuds with your phone, use a wireless mouse or keyboard with your computer, stream music from your phone/tablet/computer to a Bluetooth speaker, etc.
Bluetooth is similar to Wi-Fi in that it is wireless and will go through walls (with some loss of signal strength), and it uses less power than Wi-Fi (so your batteries can either be smaller, and/or will last longer between charges), but Bluetooth has a shorter range.
Setup (Pairing)
When you purchase a Bluetooth device (e.g. headphones), the first time you use it, you will need to pair it with your other device (e.g. your phone, tablet or computer). Pairing typically follows steps similar to these:
- Put the first device (e.g. wireless headphones) in pairing mode. How to do this varies from device to device, so read the manual that came with your device (it usually involves holding a button (or buttons) down on your device for a period of time. Often, lights will flash on the device to indicate that it is in pairing mode.
- Go to the Bluetooth Settings on your other device (e.g. phone, tablet, computer), and have this device search for other Bluetooth devices. When you see the device you want, “pair” with it.
- If your first device has a screen (e.g. a TV), you will likely see a code on the screen that you need to enter into your phone/tablet/computer. The code is to prevent someone within Bluetooth range (33 feet or less) from connecting to this device (e.g. your next door neighbour in your apartment building).
- Exit Pairing Mode on the first device. This is usually automatic once pairing is complete, and if you don’t complete pairing within a certain amount of time, your device will likely exit pairing mode automatically. This feature is designed to protect you from someone else nearby pairing with your device.
Some Bluetooth devices support pairing with multiple devices, for example, you may be able to pair your wireless earbuds with both your phone and computer (or tablet).
Novel Bluetooth Uses
Epidemic Contact Tracing
Contact tracing is the process of identifying people who have had close contact with an infected individual (e.g. COVID 19). Traditionally, this relied on the memory of an infected person to tell public health officials about their movements, and the people they may have come into close contact with. Bluetooth is now being used as a means of tracking other mobile phones that come within range of your mobile phone during pandemics.This sort of data can be useful for public health officials in determining whether social distancing guidelines are being followed, as well as when a user has been close to someone who later tests positive.
During COVID-19, China developed tracing technology and required its citizens to use it. Users enter their names and identification