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As a fashionable tech youth, there are a few products that enhance personal charm in life: Bluetooth headsets, Bluetooth mice, Bluetooth speakers, smart wristbands…
Just buying one, even if you haven’t started using it, will make you feel like your life has instantly upgraded in quality, and the tech attributes are off the charts.
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The term Bluetooth is something we are all very familiar with. But what exactly is Bluetooth, since you use it every day?
This story starts with a Danish king
Bluetooth is actually a short-range wireless communication technology, a global open standard for wireless transmission of voice and data.
But why is it called “blue”?
This can be traced back to the 10th century Danish King Harald Blåtand.
King Harald ruled Denmark from around 958 to 986 AD. He was a great warrior who ended the Viking Age and unified much of Scandinavia, including present-day Norway, Sweden, and Denmark.
The Danish word “Blåtand” translates to “Bluetooth” in English, hence he is also known as King Harald Bluetooth.
There are many versions about the origin of this name; one legend suggests that the king loved to eat blueberries, which stained his teeth blue. Some historians speculate that one of the king’s teeth had decayed and appeared blue in color.
In 1996, Ericsson, Nokia, Toshiba, IBM, and Intel planned to establish an industry association to jointly develop a short-range wireless connection technology. The development team hoped that this wireless communication technology would coordinate and unify the work across different industries, much like King Bluetooth did.
Thus, the technology was named Bluetooth.
The Bluetooth logo is a combination of the ancient Nordic letters ᚼ and ᛒ, which represent the initials “HB” of King Harald Blåtand.
Thanks to this magical logo, the story of this Danish king will indeed be remembered for ages.
Meaning of the Bluetooth logo
Why should I still use Bluetooth?
As both are short-range communication technologies, Bluetooth is inevitably compared with Wi-Fi technology. So what are the differences between the two?
First, in terms of usage, we often connect multiple devices to the same Wi-Fi to access the internet, which is a one-to-many connection; whereas Bluetooth allows data transmission between two devices, which is a point-to-point connection.
This aspect suggests that Bluetooth has a higher data security.
Secondly, Bluetooth uses microstrip antennas, which are small and easy to integrate into devices, and Bluetooth modules are very low-cost, leading to a high penetration rate of Bluetooth devices. In contrast, Wi-Fi devices require separate network cards and routing devices, which are more expensive and consume more power.
In some scenarios, Bluetooth is more suitable than Wi-Fi.
For example, friends in Shanghai often use an app called “Metro” when riding the subway.
Image source: Shanghai Local Treasure
To protect passengers’ property security and prevent QR codes from being fraudulently scanned;
The app requires users to enable Bluetooth during use, so that the gate and mobile phone can verify each other, and the gate will only open after verification.
If this app used network or Wi-Fi for authentication, poor network conditions on the passenger’s phone could affect their ability to enter or exit the gate.
In this case, using Bluetooth for secure authentication is a more suitable solution.
Does turning on Bluetooth consume battery?
But if I have to keep Bluetooth on just to ride the subway, will that drain my phone’s battery?
To understand this issue, you need to know about the new developments in Bluetooth technology.
Currently, there are two types of Bluetooth we use: traditional Bluetooth and Bluetooth Low Energy (BLE).
Traditional Bluetooth uses a point-to-point communication method, which maintains a continuous connection and is generally used in scenarios with large data volumes.
For example, Bluetooth headsets and speakers use this connection method.
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Compared to traditional Bluetooth, the greatest advantage of BLE is its fast search and connection speed and low power consumption. A BLE connection (scanning devices, establishing connections, sending data, etc.) takes only about 3 milliseconds. Once the task is completed, it quickly switches to a “non-connected” state, minimizing power consumption.
However, BLE has a physical bandwidth of only 1 megabit, resulting in a lower data transmission rate, so BLE is generally used for devices that require high real-time performance but have very small data packets, such as keyboards and remote controls.
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Using the “Metro” app as an example, this app utilizes BLE technology.
When passengers pass through the gate, the software can quickly establish a connection with the gate via BLE and complete the authentication process, which is nearly imperceptible to the passengers and does not increase their waiting time at the gate.
Moreover, due to the use of BLE technology, the Metro only needs to send a small data packet to the gate. After authentication, Bluetooth quickly enters a “non-connected” state, greatly reducing power consumption, making the energy used negligible for the phone.
Whether commuting to work, listening to music on the subway, or working wirelessly, the use of Bluetooth technology has made our lives more convenient.
Next time you turn on Bluetooth, don’t forget to thank that engineering romance from Northern Europe and that distant Viking-era Danish king.
[1] https://gizmodo.com/bluetooth-is-named-after-a-medieval-king-who-may-have-h-1671450657
[2] https://en.wikipedia.org/wiki/Harald_Bluetooth
Main Reviewer丨Chen Yong Responsible Editor丨Dan Zhicao
Source丨Science Popularization China WeChat Official Account Guo Ke
