Bluetooth

A wireless personal area network (WPAN) standard for short-range transmission of digital voice and data. Bluetooth is widely used for hands-free cellphone operation, including wireless headsets and connecting to Bluetooth-enabled automobiles that turn the car's audio system into a speakerphone. It can also be used to transfer data between cellphone and computer. Although Bluetooth refers to the transmission technology, the term has practically become synonymous with cellphone applications. See WPAN.

Specifications
Supporting point-to-point and multipoint applications, Bluetooth provides up to 720 Kbps data transfer within a range of 10 meters and up to 100 meters with a power boost. In 2004, Bluetooth 2.0 + EDR (Enhanced Data Rate) was introduced with a different encoding scheme that increased the data rate to 3 Mbps.

Unlike infrared technology (IrDA), which requires line of sight between transmitter and receiver, Bluetooth uses omnidirectional radio waves that can transmit through walls and other non-metal barriers.

Governed by the Bluetooth Special Interest Group (www.bluetooth.com), founded in 1998 by Ericsson, IBM, Intel, Nokia and Toshiba, Bluetooth transmits in the unlicensed 2.4 GHz band. It uses a frequency hopping spread spectrum technique that changes its signal 1600 times per second. If there is interference from other devices, transmission continues, but speed is downgraded. See WiMedia Alliance.

King Blatan of Denmark
The name Bluetooth comes from King Harald Blatan (Bluetooth) of Denmark, who in the 10th century, began to Christianize the country. Ericsson, a Scandinavian company, was the first to develop the specification. See Bluejacking, Bluesnarfing, Bluetooth virus, Cabir, PAN, wireless adapter and wireless LAN.

Two Wireless Systems

The first major Bluetooth application was for cellphone headsets such as this Cardo Systems unit (www.cardowireless.com). This means using two wireless systems: Bluetooth between ear and cellphone and CDMA or GSM between cellphone and cell tower.

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(protocol, standard)

Bluetooth - A specification for short-range radio links between mobile computers, mobile phones, digital cameras, and other portable devices. http://bluetooth.com.