Bluetooth technology – Definition, Applications, Advantages

Bluetooth technology – Bluetooth Technology supports ad-hoc piconets. Ad-hoc piconets are local area networks with a very short coverage area. It doesn’t require any kind of infrastructure.

Bluetooth Definition

Bluetooth is a wireless technology that is used for exchanging data between a variety of fixed and mobile devices over a very short diameter with the support of short-wavelength UHF radio waves provided by scientific, industrial, and medical radio bands, with 2.402 to 2.480 GHz.

What is Bluetooth technology

Bluetooth technology allows connecting a variety of devices in close proximity about 10 meters without the use of wiring or wireless infrastructure.

The gross data rate is about 1 Mbit/s. It can be used for asynchronous (data) and synchronous (voice) data exchange.

Many devices offer an infrared data association (IrDA) interface with transmission rates of, about 115 kbit/s or 4 Mbit/s.

There are some problems with IrDA due to its very limited range (on average 2 m for built-in interfaces). Also, it needs a line-of-sight between the interfaces. It is usually limited to two participants, which means, only point-to-point connections are supported.

IrDA has no internetworking functionalities. It has no media access, and also no enhanced communication architecture.

The main advantage of IrDA technology is its low cost, and also it is found in all mobile devices such as laptops, PDAs, mobile phones, tablets, etc.

What is Bluetooth used for

Bluetooth Technology – User scenarios

Various User Scenarios can be possible for Bluetooth technology-based wireless piconet

Connection of peripheral devices

A variety of devices are connected to a laptop, desktop, mouse, mike, speaker, etc using a wired connection. People can use Bluetooth facility to communicate and transfer data.

Support for ad-hoc networking:

People communicate with each other via, mobile phones, laptops, etc. Using small personal digital assistant teachers and students transfer data via Bluetooth chips built-in with the devices.

Bridging of networks:

Using wireless piconets, a cell phone can be connected to a Personal Digital Assistant, laptop and tablet, etc in a simple way.

Cell phones don’t have WLAN adapters built-in, but they could have a Bluetooth chip built-in facility. The cell phone can act as a bridge between the local piconet and, the global GSM network.

For example, on arrival at an airport, your mobile phone could receive e-mail via GSM and you can forward it to the laptop which is still in your bag. Via a piconet, a fileserver can update local information stored on a laptop while the person is walking.

Bluetooth to track COVID-19

The recent application of Bluetooth technology is to warn about COVID-19 by tracking contacts of the nearby person who has been found COVID-19 positive.

What is Bluetooth technology and how does it work

Bluetooth Architecture

Bluetooth works on 79 channels in the 2.4 GHz band with 1 MHz carrier space. Bluetooth devices perform frequency hopping with the 1,600 hops/s in a pseudo-random style.

Bluetooth technology operates via piconet

Bluetooth Piconet

A piconet is a group of Bluetooth enabled devices. All these devices are synchronized to the same hopping pattern.

Devices in the piconet operate in the following pattern-

One device in the piconet acts as a master device called -M, all other devices connected to the master act as slave devices called -S.
The master device decides the hopping sequence pattern in the piconet and the slave devices have to synchronize to this hopping sequence pattern.
Each piconet has a unique hopping sequence pattern. If any device needs to participate in the piconet, the device has to synchronize to the current hopping pattern.
Two additional devices are also there called parked devices or P and Standby devices or SB.
This parked device can not actively participate in the piconet (It means these devices do not have a connection currently), but they are known devices and can be reactivated within a period of time or within some milliseconds.
Devices in standby (SB) do not participate in the piconet.
Each piconet has one master device and up to seven slave devices.
More than 200 devices can be parked devices.
The reason for the upper limit of eight active devices is the 3-bit address used in Bluetooth.
If a parked device needs to communicate and there are currently seven active slave devices, then one slave device has to switch to the Park mode in order to permit the parked device to switch to the active mode.
All active devices have to use the same hopping sequence and they must be synchronized.
The first step involves a master device sending its clock and device ID.
All Bluetooth devices have the same capabilities, which means either they can be a master or a slave device.
There is no difference between terminals and base stations, any two or more devices can form a piconet.
The device initiating the piconet automatically becomes the master, all other devices will become the slaves.
The hopping pattern is determined by the device ID, a 48-bit worldwide unique identifier. The phase of the hopping sequence is decided by the master device’s clock.
After setting the internal clock according to the master device a slave device may participate in the piconet.
All active devices are given a 3-bit active member address or AMA. All parked devices use an 8-bit parked member address or PMA.
Devices that are in standby mode do not need any address. All users within one piconet have the same hopping sequence and share the same 1 MHz channel.
As more and more devices join the piconet, the throughput per device reduces speedily.
Only those devices that really exchange data share the same piconet at a time, hence, many piconets with overlapping coverage may present simultaneously. This overlapping coverage area is called scatternet.
In the case of the scatternet consisting of two piconets, in which one device participates in two different piconets, both the piconets use a different hopping pattern, determined by the master of the particular piconet.

Bluetooth applies FH-CDMA for the separation of two or more piconets.

What is the difference between WiFi and Bluetooth

Bluetooth is used to connect 7 devices without wires or cables, while WiFi gives you high-speed access to the internet.

Bluetooth is a wireless technology that allows you to exchange data over a short distance while WIFI provides you to connect as many devices as you wish.

Wifi the maximum limit of connections depend on Wi-Fi router which can accommodate up to several communicating devices at a time.

Do laptops have Bluetooth

Now all the electronic devices come with builtin Bluetooth technology

Bluetooth technology – Definition, Applications, Advantages