In the years near 950 AD, a Viking king named Harold Bluetooth (Harald Blåtand in Danish) united Denmark and Norway. The initial study on wireless connectivity of electronic devices was conducted by Ericsson Mobile communications in Sweden, and so it was natural for them to adopt Bluetooth as the name to “unite” wireless connectivity between devices within a “personal operating space,” defined, at first, by a 10-meter circle. Bluetooth is aimed at providing wireless connectivity between personal electronic devices from 1m to less than 100 m distances. Since Bluetooth is a radio system, the distance criteria depend on the transmitted power, the receiver sensitivity, propagation path characteristics, and what is in proximity to the antennas used. (Also see this chapter’s last section, Power Consumption.)

Bluetooth technology provides such wirelessly connected devices the possibility of creating an ad hoc network, often referred to as a Wireless Personal Area Network (WPAN). In 1998, the Bluetooth Special Interest Group (SIG) was formed. Since then Ericsson, 3Com, IBM, Intel, Lucent, Microsoft, Motorola, Nokia, Toshiba, and thousands of others have worked together for the purpose of developing a global wireless network standard that could be used worldwide. Bluetooth standard 1 (IEEE 802.15.1) and then standard 2 (often referred to as enhanced data rate or EDR) are the resulting compatible technologies (Bing, 2002, and Nathan, 2001).