WHAT IS BLUETOOTH TECHNOLOGY ? And why so popular now a days

Bluetooth, named after the renowned Danish King, Harold Bluetooth, is a short-range wireless connectivity standard.

Bluetooth is capturing the minds of the present day technologists, as a technology enabler for the wireless unification of a wide variety of portable devices like mobile PCs, mobile phones and the like. It does away with the cables and enables voice and data transfer between the devices through wireless networks called piconets.

The primary segments identified for Bluetooth application are: Cellular & PCS Mobile Phones, Digital Cordless Phones, Data Access Points, PC Cards and Adapters , Notebook & Desktop PCs, Handheld PCs & Palm Companions / PDA s, Digital Still Cameras, Output Equipment, Automotive and Industrial & Medical applications.

The technology behind it:
Bluetooth is a Radio Frequency (RF) specification for short-range, point-to-multi-point voice and data transfer. An advantage of Bluetooth is it's similarity to many other specifications already deployed and it's borrowing of many a feature from these specifications. The 2.4GHz band is used by IEEE 802.11 to enable wireless LAN connectivity. Bluetooth borrows specifications to enable file sharing and data transfers between devices from IrDA (a wireless specification that uses InfraRed light to connect devices). HomeRF SWAP, a specification aimed at small network of devices for the home environment, is another source for Bluetooth.
It is omni-directional and has a present nominal link range of 10cm to 10m, which can be extended to 100m, with increased transmitting power. Bluetooth operates in the 2.4GHz Industrial-Scientific-Medical (ISM) Band and uses a Frequency Hop (FH) spread spectrum technology in which packets are transmitted in defined time slots on defined frequencies. A full duplex information interchange rate of upto 1Mbps may be achieved in which a Time-Division Duplex (TDD) scheme is used.

A Bluetooth System:
* A Radio Unit - consisting of a radio transceiver, which provides the radio, link between the Bluetooth devices.
* A Baseband Unit - a hardware consisting of flash memory and a CPU. This interfaces with the radio unit and the host device electronics.
* Link Management Software - a driver software or firmware which enables the application software to interface with the baseband unit.
* An Application Software - this implements the user interface and is the application that can run on wireless.