What is Bluetooth
is a wireless technology that enables any electrical device to
wirelessly communicate in the range of 2.5 GHz ISM frequency
band. Mobile phones, headsets, PDA's and portable computers can
communicate and send data to each other without wires or cables
to link to devices together. The name of Bluetooth derived from
the name of an English king Harold Bluetooth.
It a low
cost, low power, radio technology, which is particularly suited
to the short range Personal Area Network (PAN) application.
Bluetooth Special Interest Group is authorized to develop its
specifications & license.
Features of Bluetooth are given below:
operates in the 2.4GHz frequency band without having a
license for wireless communication.
10-100 meters data can be transfer in real time.
proximity & accuracy is not required for Bluetooth as in
case of infrared data (IrDA) communication device. Bluetooth
does not suffer from interference from obstacles such as
walls while infrared suffers due to obstacles.
Bluetooth supports both point-to-point and
point-to-multipoint wireless connections without cables
between mobile phones and personal computers.
transfer rate of blue tooth varies from version to version.
Data rate of 1 Mbps for Version 1.2 Up to 3 Mbps for Version
parts of Bluetooth system are RF transceiver, base band, and
protocol stack. Bluetooth is used for
small-area networking without user intervention. Due to
extremely low transmission power in Bluetooth technique
power is saved. It is a networking standard that works at two
Due to these levels mobiles have to agree on these levels when bits are
sent. It decides the amount of data to be sent at a time, and how the
parties in a conversation can be sure that the message received is the
same as the message sent.
networking transmits data through low-power radio waves. It can
connect up to eight devices simultaneously. With in the range of
about ten meters you must think that the devices will not interfere
with each other. Bluetooth solved the problem of devices
interference while sending the data by using the technique of
Spread-Spectrum Frequency Hopping due to which devices may transfer
data at the same frequency at the same time.
The question rises here is how
Bluetooth send the same data using same frequency band without
devices interferences? In Bluetooth technique, transmitters change
frequencies 1,600 times in every second. In this way devices can
make full use of a limited band of the radio spectrum.
devices came into the range of each other, conversations take place
automatically. This conversation automatically determines whether
they have the data to share or not. In this way Bluetooth devices
not only share the data but also control the data to be transferred.
When the connection is established, the devices either they are part
of a computer system or a network, Bluetooth systems create a