Bluetooth Basics - Bluetooth Technology Tutorial

By Jason Kohrs

Bluetooth Basics

Bluetooth technology is nothing new, but in many respects it still seems to be more of a buzz word rather than a well understood, commonly accepted technology. You see advertisements for Bluetooth enabled cell phones, PDAs, and laptops, and a search of the Geeks.com website shows all sorts of different devices taking advantage of this wireless standard. But, what is it?

History

Before getting into the technology, the word Bluetooth is intriguing all on its own, and deserves a look. The term is far less high tech than you might imagine, and finds its roots in European history. The King of Denmark from 940 to 981 was renowned for his ability to help people communicate, his name (in English)... Harald Bluetooth. Perhaps a bit obscure, but the reference is appropriate for a wireless communications standard.

Another item worth investigating is the Bluetooth logo. Based on characters from the runic alphabet (used in ancient Denmark), it was chosen as it appears to be the combination of the English letter B and an asterisk.

Capabilities

The FAQ on the Bluetooth.org website offers a basic definition: "Bluetooth wireless technology is a worldwide specification for a small-form factor, low-cost radio solution that provides links between mobile computers, mobile phones, other portable handheld devices, and connectivity to the Internet."

Just like 802.11 b/g wireless networking systems and many cordless telephones, Bluetooth devices operate on 2.4 GHz radio signals. That band seems to be getting a bit crowded, and interference between devices may be difficult to avoid. Telephones are now being offered on the 5.8 GHz band to help remedy this, and Bluetooth has taken its own steps to reduce interference and improve transmission quality. Version 1.1 of the Bluetooth standard greatly reduces interference issues, but requires completely different hardware from the original 1.0C standard, thus eliminating any chance of backwards compatibility.

The typical specifications of Bluetooth indicate a maximum transfer rate of 723 kbps and a range of 20-100 meters (65 to 328 feet - depending on the class of the device). This speed is a fraction of that offered by 802.11 b or g wireless standards, so it is obvious that Bluetooth doesn’t pose a threat to replace your wireless network. Although it is very similar to 802.11 in many ways, Bluetooth was never intended to be a networking standard, but does have many practical applications.

Practical Applications

There are a variety of products that take advantage of Bluetooth’s capabilities, from laptops and PDAs, to headphones and input devices, and even wireless printer adapters.