Information Technology Reference
In-Depth Information
2
Bluetooth
Bluetooth is an industrial specification for exchanging data over short
distances creating wireless personal area networks (WPANs). It
represents a standard, secure and cost-effective method for information
exchange among devices over a short-range radio frequency (RF)
physical media.
Bluetooth was initially developed in 1994 by Ericsson [1] to allow mobile
devices to communicate within a 30 feet (
~
10 m) range as a wireless
alternative to RS232 data cables. In 1998, several majors in the technological
field, such as Ericsson, IBM, Intel, Nokia and Toshiba, established the
Bluetooth Special Interest Group (BT-SIG). From then on, more than 11,000
companies joined the BT-SIG and also all cellular phones and personal
digital assistant (PDA) manufacturers.
Despite its unique features, Bluetooth is based on other previously
existing wireless solutions, such as Motorola PIANO, IrDA, IEEE 802.11
and digital enhanced cordless telecommunications (DECT).
PIANO was designed to set up ad-hoc PANs. This feature was considered
by the BT-SIG to improve the initial goal that envisaged Bluetooth only as a
cable replacement. The full-duplex audio stream transmission is inherited
from DECT and it is mainly used for wireless headsets. Raw data exchange
is inherited from IrDA, whereas FHSS modulation within the ISM band,
authentication, privacy and power management techniques come from IEEE
802.11.
The name is inspired by King Harald Blåtand of Denmark, an able
diplomatic that joined all Scandinavian people together and introduced the
Christian faith in the region. The Bluetooth inventors thought that this
could be a suitable name for a technology aiming at the definition of a
unique communication protocol among different devices (the same way as
the king Blåtand joined people together).
Bluetooth is therefore a short-range wireless technology, now defined by
the IEEE 802.15 standard, designed for data exchange among different
electronic devices. Bluetooth has low energy requirements, thus making
possible its integration within a large variety of devices, ranging from PCs
and laptops to small peripherals, such as PDAs and cellular phones. Such
devices can therefore interact with each another, thus allowing for
audio/video exchange, internet connection sharing and all communication-
based activities.
A Bluetooth radio can be embedded in a device or can be added
afterwards, as for instance the pen drive-size radios with the USB hardware
interface.
