How does Bluetooth work and how data is transmitted wirelessly?

Day after day, hour after hour, you exchange photos, videos, and music with your friends over the phone, without the need for connections and without having to use a third party device to be the link between you, you may have once wondered how this technology saves you A lot of costs, effort and time, in addition to being the best solution for file sharing – all kinds of files – whatever it is, and even more so, today as we approached the middle of the seventeenth millennium, the scope of the use of Bluetooth technology is no longer limited or limited only in exchange Files, we’re here in the IoT era Or the Internet of Things ”, you are able to control almost everything in your home from one location, without having to go somewhere to press a button or connect one of the links, you can turn on and turn off the lighting and open the electric oven and open the doors and do all Almost anything in your home or office from one place with just a few pulses on a concrete screen or buttons.

Let us learn through today’s article about how one of the most important technologies of modern times works, the most beneficial to humanity, most notably, the future of humanity beyond 2020.


Formerly known as “Short-Link Radio Technology” or “ short-range radio technology”, a radio wave technology specifically designed for short-range communications of no more than 30 feet or 10 meters, the technology uses short-length radio waves High-frequency short-Wavelength (UHF Radio Waves) in the band “ISM” Industrial, Scientific and Medical between 2.4 to 2.485 GHz, to create personal networks in a specific range “PANs”.

The technology is managed by the Bluetooth Special Interest Group “SIG”, which includes more than 30,000 member companies in the field of communications, computing and networks in addition to consumer electronics, where each device manufacturer needs to meet the specifications of their device Bluetooth SIG standards in order to start advertising for a device using Bluetooth technology . Developed by Nis Rydbeck in 1989, he worked for Ericsson Mobile in Sweden, as well as Johan Ultman.

Initially, the development of technology was to make wireless headphones. Rydbeck asked Tord Wingren, specifically Jaap Haartsen and Sven Mattisson, who was working for Ericsson, the required specifications based on FHSS technology, or Frequency-Hopping Spread Spectrum, to make a suitable alternative to connectors. RS-232 for data transfer, where Bluetooth was able to connect up to seven devices simultaneously without interrupting each other, which overcame the problems of previous technologies and links.

The name Bluetooth came from the name of the Scandinavian King Harald Bluetooth from the eighteenth century because it is one of the best examples of this technology on the ground that it was the unification of the disharmonious Danish tribes under the command of one kingdom. This name was proposed by Jim Kardach in 1997 and for those who do not know, Kardach is the developer of the system that allowed computers and phones to communicate together. Harald Bluetooth.

The logo consists of two components:

  • The letter H in Scandinavian known as Younger Futhark is pronounced Hagali and stands for the first name of Harald.
  • The letter B, which is also pronounced Bjarken in Scandinavian, stands for Bluetooth.

How Bluetooth works

Here we turn to the most important points of our topic today, how this technology works, I will take an example in trying to simplify it for you, let’s talk for example on wireless speakers and connect them to the phone via Bluetooth.

First, in order for each device to communicate with each other via Bluetooth technology needs a programmatic part and a physical part, the physical part is an air chip in both devices that send and receive waves over a certain frequency, while the software part is what is known as “interpretation” of incoming signals And send it to the device in a way that it can read. In this way, when you create the communication language between the two devices, the phone learns how and how it sends audio files and information in the way that the speakers understand, as well as the role of the speakers in the interpretation of the commands issued by the phone such as reducing and raising the volume and control sections.

In most cases, when you activate the Bluetooth feature in either of the devices will become one of them discoverable by the other and of course in this case, the headset is discovered by the phone, the speakers also send a little information to the phone and this is the most important role in this process, and that To alert the phone that it is ready and ready to receive information from him to become under his command to form a personal network limited region between both devices or as mentioned previously PAN.

But you might be wondering, how do you not mix Bluetooth signals in one place? The answer lies in the signal addresses of each of the browsers. Even if there are signals from other devices with the same wavelength of those devices, each wavelength signal of these lengths has a specific address that can be detected and read so that data can only be exchanged between compatible devices. Also, Bluetooth technology works as mentioned earlier in a limited range, which is no more than ten feet, which certainly prevents the presence of many signals in this small space to cut signals between each other.

According to, the site for this great technology, it works in the range between 2.4 to 2.485 GHz, and through the so-called spread-spectrum frequency hopping at 1600 hops/sec.

Well, you may be satisfied with those numbers, let me simplify it better

The mission of the Bluetooth chip is to release wavelengths in a specific area of ​​frequencies for short-range communications. However, the possibility of other devices transmitting other wavelengths and ready to receive the wavelengths of other devices means that there is a risk that wavelengths may interrupt each other, especially those in the same small band at the same or near frequencies.

The solution was to make signals known as Hops or hops during frequency. As mentioned, for Bluetooth, signals jump between frequencies around 1,600 hops per second, and of course, the probability of having two equal frequencies from two different devices is a probability of not more than 0.00125 percent.

It’s not the same for wireless headsets that use Bluetooth, as they use full or partial duplex connectivity. A full-duplex connection means that all connected devices are capable of transmitting and receiving signals, meaning that the conversation that occurs between the two devices, in this case, will become two-way instead of one-way. Same time.

Less power, less speed

Bluetooth technology is a technology as directed to transfer data in the short term, and is the best option for transferring data between mobile phones, and the reason for this is one thing in the interest of another thing, which is the low energy consumed by the Bluetooth chip in your phone, which makes it, of course, do not send Files and information over a long-range and don’t send them at high speed. The technology is dedicated to the transfer and exchange of information within 10 meters, and even segments used in the factories do not exceed a range of 300 feet or 100 meters.

For example, Bluetooth 4.0 came with a range of up to 200 feet instead of 33 feet in Bluetooth 3.0, with a maximum transfer speed of 25 Mbps with less power consumption, and Bluetooth 5.0. Which reached a range of 800 feet or 240 meters and the transfer speed of 50 Mbps per second.

Bluetooth or WiFi

This question was one of the most important questions I wrote in the draft article because it is very different and there is a lot of confusion between Bluetooth and Wi-Fi, both of which ultimately aspire to get to what you want without the need to use any wires.

Bluetooth technology is always used in short distances and is used to transfer small amounts of data. Unlike WiFi, it is safer, less energy-consuming and automatically connected. Wi-Fi is used to transfer large amounts of data between computers and the Internet.

Is using Bluetooth harmful?

There is virtually no technology on earth that has not been talked about health damage, wherever it is, wherever it is used, how it is used, and of course, our friend has not been safe from this matter. It is not true, because the frequency of radio waves propagates in the range from 2.402 to 2.480 GHz, which is ionized and harmless. Also, the maximum output power of Bluetooth radio waves is 100mW, which causes no harm to the body at all.

What happens if Bluetooth is let activated on the phone?

The real consumption of the Bluetooth chip in your phone is through the transfer of data between your phone and other devices. If you leave the phone and connect it even to a device that knows it without transferring data, for example, connect it to a music player without playing music already, it means that it will not make an effort in transferring data , Or even effortlessly searching for nearby Bluetooth devices, meaning the power consumption is 0.

This was all I found about Bluetooth technology, one of the qualitative transitions in history, which saved us a lot and a lot of time, effort, costs and even places. We no longer need spaces to connect wires and also saved us the dangers of wires that could cause some of us to happen. If you know anything else about this great technology, join us in the comments for Ali and other readers of what you might add.