Bluetooth

By: Michael Nelson

Bluetooth Technology is the use of wireless communication between certain electronic devices.  Bluetooth was designed with the concept of getting rid of all the wires that are use to connect electronic devices that enable the devices to communicate back and forth like between a computer and a printer, or between a cell phone and an earpiece.  Bluetooth works on a secure, low cost, globally available short range radio frequency. 

Bluetooth technology allows two devices to communicate to one another when the devices come with in the radio frequency of the other devices.  The current ranges of the three power class are 328 feet, 32 feet, and 3 feet.  It is important to note that distances for the different power class are of there maximum ranges and under normally usage of a Bluetooth device the distance is about half that.  The specification was first developed by Ericsson, and was later formalized by the Bluetooth Special Interest Group (SIG). The SIG was formally announced on May 20, 1999.  It was established by Sony, Ericsson, IBM, Intel, Toshiba and Nokia, and later joined by other companies as associates or adopted members. 

In April, 1998, Intel and Microsoft formed a consortium between themselves and IBM, Ericsson, Nokia, Toshiba and Puma technology and adopted the code name Bluetooth for their proposed open specification.             

Bluetooth is named after the Danish King Harald Blatand (the translation of Blatand in English is Bluetooth), King of Denmark and Norway from about 935 to his death in about 986, known for his unification of previously warring tribes from Denmark, Norway and Sweden. Bluetooth likewise was intended to unify different technologies like computers and mobile phones. The actual Harald Blatand that was referred to in naming Bluetooth was most probably the liberal interpretation given to him. The Long Ships by Frans Gunnar Bengtsson, a Swedish best-selling Viking inspired novel.           

A Bluetooth device playing the role of the “master” can communicate with up to 7 devices playing the role of the “slave.”  At any given time, data can be transferred between the master and one slave; but the master switches rapidly from slave to slave in a round-robin fashion. Simultaneous transmission from the master to multiple slaves is possible, but not used much in practice.  These groups of up to 8 devices (1 master and 7 slaves) are called piconets.  Either device may switch the master/slave role at anytime.
The Bluetooth specification also allows connecting two or more piconets together to form a scatternet, with some devices acting as a bridge by simultaneously playing the master role in one piconet and the slave role in another piconet.  These devices have yet to come, though are supposed to appear within the nest two years.

Bluetooth applications are being use between desktops, laptops, printers, mice, keyboards, PDA’s, mp3 players, Digital Cameras, cell phones, and now in some Luxury cars such as Acura, BMW, Toyota Prius and Lexus.

Sources

http://en.wikipedia.org/wiki/bluetooth