What is Bluetooth? & How it works? (Step-by-step)

Bluetooth is a commonly used technology in our day-to-day lifestyle. Do you ever think, How Bluetooth is working and what type of technology used in it? You came to the right place to know.

As per the usual definition, we can call Bluetooth is a wireless connection or wireless technology but according to the technical terminology, we can state it as…

What is Bluetooth?

Bluetooth is a wireless connecting network that is completely based on the radio frequency signals having ranges between 2.400 GHz to 2.483.5 GHz is used to connect a device with other devices (up to 8 devices). With Bluetooth, we can easily access almost all our electronic devices like phones, laptops, headphones, keyboards, mouses, TVs, etc.

We make a habit to use Bluetooth technology every day because nobody wants to get into trouble with wired gadgets.

Bluetooth has a reason behind its name and symbol.

Bluetooth Name :

Bluetooth is a strange name for a network. The fact is, it is not a network name initially.

In the early stages, companies like Intel, Ericsson, and Nokia want to create a single wireless standard. Jim Kardach from Intel named this network as ‘Bluetooth’. Because once he read a historical book and inspired by the character of Viking King ‘Harald Bluetooth Gormsson’ who united two countries (Denmark and Norway). Likewise, the wireless network is also connecting two devices for communication and so he named the network “Bluetooth”.

King Harald has a Blue colored tooth and so he got this nickname ‘Bluetooth’.

Bluetooth Symbol :

If we observe the Bluetooth symbol, we found the two letters ‘H’ and ‘B’. These are the initial letters that they have taken from the King’s name Harald Bluetooth. The background of the symbol is also blue.

Bluetooth symbol

Who invented Bluetooth?

In 1989, Dr. Nils Rydbeck was the chief technology officer at Ericsson mobiles and he collaborated with Dr. Johan Ullman who has an idea about Bluetooth for the first time. They find Dr.Jaap Haartsen who is capable to do the work that they want.

After five years of Dr. Jaap’s effort, he made the first protocol of Bluetooth. But it is not perfect then. So he took years to perfect the Bluetooth technology and present the first Bluetooth headset in 1999 at Comdex company exposition and trade show in Las Vegas.

They even got the best show award in the exposition. But the problem is security.

You can find the Bluetooth security information in the working section. So, you can clearly understand the topic.

Bluetooth Special Interest Group

Intel, IBM, Ericsson, Nokia, and Toshiba formed a group especially to develop Bluetooth technology in 1998. It was running with the collaboration of almost 30,000 companies with the name Bluetooth SIG (Special Interest Group).

Anybody can join the Special Interest Group. They provide the member-only resources for the Adopter membership. They also have a Business level membership called Associate membership.

How does Bluetooth work?

To make you understand clearly, I want to classify the working of Bluetooth into four steps.

  1. Network forming
  2. Data sharing
  3. Security and
  4. Network range

Network forming :

In the very first step, network forming is the primary part of the Bluetooth working. Piconet uses the Bluetooth protocols to form a network. But what is a Piconet mean?

Piconet :

A Piconet is a network that links a group of devices that are using Bluetooth technology protocols. It comprises 8 stations. One station occupied with the ‘Master’ and the other 7 stations is for ‘slaves’. Master has entire control either add or remove slaves or cancel the entire network.

The Bluetooth chip has a radio device, responsible to modulate and transmit data through the radio signals, and also the chip has a digital controller. It works like a CPU and has a protocol to interact with the device we are using called Link controller protocol. And also software called Link manager that has the function of communicating with other devices.

In each network, there must be a master and a slave, and more slaves can join up to 7. Network forming is the same in all versions.

With Piconet, we complete the network forming and now we want to share the files.

Data sharing :

We already know that Bluetooth uses radio wave signals for file transferring. After the formation of a network, it forms 79 different channels between the network-connected devices.

Each paired or slave device is used to find the new empty channel to connect with the master device for file transferring. If the channel is already occupied by the other devices in a network, then the new pairing device will find the new channel.

Bluetooth is used to change its frequency every time that is almost 1600 times a second. So there is no problem with jamming the signals. Here you can find what frequency means?

The speed of data sharing depends upon the version we are using. The maximum speed of file transferring with the latest version of Bluetooth is 24Mbps.

Security :

The real problem arrives here. There are three types of security threats to the Bluetooth network.

  • Bluebugging
  • Bluejacking and
  • Bluesnarfing

Bluebugging –

Blue bugging is a type of malware that enters our devices by turning on Bluetooth and make it discoverable. With Blue bugging, the hacker can get all kinds of data in our device, like Apps, images, videos, documents, etc. It is a difficult hacking method than Bluejacking and Bluesnarfing.

People gathering places or busy places have a high possibility of this type of hacking. And some preventive steps are…

  • Turn off ‘discovery mode’ on your device
  • Avoid using local or untrusted networks.

Bluejacking –

Bluejacking means receiving spam messages from unknown sources by just enabling the discovery mode in our device. It contains less harm, or no harm compared to Bluebugging and Bluesnarfing.

We can avoid Bluejacking by simply turning off the ‘discovery mode’.

Bluesnarfing –

Bluesnarfing means reading our phone data and manipulate or misuse it. It is a harmful malware attack than Bluejacking. This malware can enter our device even if we turn off the discovery mode in our device.

By all the three security threats, we understand that turn on the Bluetooth and discovery mode only if required. And don’t trust the unknown public source connection for pairing.

Range :

Bluetooth range increases from 1.0 to 5.2 means 10 to 400 meters, respectively. And this is the maximum range to connect two Bluetooth devices on the outdoor ground. This is the practical number given by the Nordic Semiconductor.

The range may vary from version to version. In version 1.0, the network connection is only possible up to 10 meters range. But now, with version 5.0, we can connect from the 100 to 400 meters range.

Bluetooth Versions :

A version of a device or software tells us about its efficiency. Bluetooth has changed a lot from version1.0 to 5.2 in various aspects like security, user friendly, Low Energy, connectivity range, etc.

The latest version of Bluetooth is version 5.2. Any version in the market released by the Bluetooth SIG group. Let’s see the evolution of Bluetooth.

Version 1.0 :

It is the first version of Bluetooth from SIG. It has a bad interface with a lot of problems while using it. In fact, in 1.0 and 1.0B, we need to add a Bluetooth hardware device address for pairing.

They release it in July 1999. The transfer speed at this version is 721 Kb/sec, which is possible to connect two devices within 10 meters range.

Version 1.1

  • Released in 2002 with IEEE Standard 802.15.1
  • Received Signal Strength Indicator placed
  • Possibility of non-encrypted channels
  • Many bugs fixed which exists on before version
  • Data transfer speed and signal range are the same as the previous version

Version 1.2

  • Officially released in 2003
  • Connecting speed improved and Discovery
  • Transmission speed increased to 1 Mb/sec
  • Improves voice quality of audio links

Version 2.0

  • Power consumption reduced
  • Data transfer speed improved up to 2.1 Mb/sec
  • Released in 2004
  • They bring near field connections for pairing

Version 2.1

  • Released in August 2007
  • They bring the best pairing technique in 2.1 called Secure Simple Pairing
  • Includes Extended Inquiry Response, to know about the device before pairing
  • Sniff subrating which allows low power consumption in low-power mode

Version 3.0

  • Released in April 2009
  • Theoretical data transfer speed enhanced to 24 Mb/sec

Version 4.0

  • Released in December 2009
  • Low Energy protocol brings a wide range of usage in many fields
  • 128-bit encryption

Version 4.1

  • Released in December 2013
  • Limited Discovery time for security purpose
  • Low Duty cycle directed advertising
  • Small devices don’t require an intermediary IPV6

Version 4.2

  • Released in December 2014
  • Security enhances
  • Internet protocol support profile ready for smart thing to home
  • Data transfer speed improved

Version 5.0

  • Released in December 2016
  • Increases data transfer speed from 25 Mb/sec to 50 Mb/sec
  • Increased the range of the network up to 400 meters

Version 5.1

  • Released in January 2019
  • The Angle of Arrival (AoA) and Angle of Departure (AoD) are used to locating and tracking the device

Version 5.2

  • Released in December 2019
  • Low Energy power control
  • Low Energy audio to pair multiple devices to a single source

Remember, the data transfer speed and the range of connectivity are based on the devices.

Bluetooth Low Energy :

Boat rockerz 400

This is my headphone. Two years back, I bought this product on Amazon, and now it works perfectly alright. The battery backup is around 7 hours, with 2 hours of charging.

The key thing here I’m saying is Bluetooth Low Energy technology use 0.01 to 0.50 W (<15 mA), which is pretty low. And at the peak stage, the maximum current is using <30 mA, which means nearly 1 W of power.

Because of this best advantage, we are using this wireless technology for different purposes like heartbeat monitoring, health monitoring, sensor alerts on mobiles, etc.

Is Bluetooth harmful?

The answer is No. According to the Food and Drug Administration (FDA), the nonionizing Electromagnetic radiations like Bluetooth, Computers, Mobiles, Wi-Fi networks, and Microwaves, etc, are not harmful to humans.

So, there is no need to worry to use this wireless technology.

Uses of Bluetooth :

  • The connection is highly protected with a password.
  • Passwords can save automatically.
  • The ‘discoverable’ feature exists.
  • Connect to our ecosystem within seconds.
  • Low power required.
  • Enable file sharing and receiving.
  • Stock feature coming with Android and Apple.
  • No harmful

These are some high noticeable features. And the coming versions may bring more features. I keep updating this page for you to get information on your figure tips.

Conclusion :

Use this wireless technology whenever required otherwise turn it off. By doing this, we don’t give a chance to hackers or malware to enter our devices. And also, we can reduce mobile battery consumption.

Protect your data by pairing with the trusted networks only.

I hope this article will make you learn something new today. Drop your mail to get informative articles like this directly to your inbox. And also, check out the YouTube channel for video content.

Author: Aswarth

Hey Guys, I'm an Electrical Engineer who is interested to learn Technical stuff in deep and want to give you the best quality information on this blog.