Bluetooth - wireless communication and network.

Introduction

Developed by Ericsson Inc., Intel Corp., Nokia Corp. and Toshiba, Bluetooth is a short-range wireless technology that allows computers, computer peripherals, and certain household appliances to communicate with each other without the need for connecting cables.

Bluetooth uses short-wave radio frequencies to transmit signals over short distances and connect a wide range of personal, professional and domestic devices together wirelessly.

Bluetooth uses FHSS in the 2.4GHz ISM band at approx 1600 hops/s. Data rates of up to 1Mbit/s over a range of 10m can be achieved (range can be extended). The communication channel can support both data (asynchronous) and voice (synchronous) communications.

Bluetooth Network

Bluetooth is designed to operate in an environment of many users. Bluetooth network actually consists of small subnets or piconets. A piconet consists of two or more connected nodes sharing the same channel. Very piconet have one master and up to 7 slaves. There is never a direct transmission between slaves. Rather all communication goes through the master.

Two or more connected piconets form a scatternet. To connect piconets simply let them have a node in common. A node may be a slave in one piconet and a master in another. This is the basis for forming ad-hoc networks in bluetooth. With ad-hoc networking, device equipped with a Bluetooth radio can establish instant connection to another Bluetooth radio as soon as it comes into range. To provide security, each link is encoded and protected against eavesdropping and interference.

Bluetooth Application

Bluetooth was designed to allow low bandwidth wireless connections to become so simple to use that they seamlessly integrate into our daily life. This low-cost, "cableless" technology can be seen in many consumer devices such as PDAs (personal digital assistants). Following are some examples of the capabilities that Bluetooth can provide consumers:

Discard the cables leading to your keyboard; mouse; speakers; and eventually, even your monitor.

Make calls from a wireless headset connected remotely to a cell phone.

Take calls over internet applications such as Skype or MSN through VoIP technology.

Hook up MP3 players wirelessly to other machines to download music.

Set up home networks so that a couch potato can remotely monitor air conditioning, the oven etc.

Call home from a remote location to turn appliances on and off, set the alarm, and monitor activity.

In business, for example, sensors and spectrometers can be fitted with Bluetooth cards or adapters to send data without using wires to a central desktop computer for analysis.

Devices that are starting to have Bluetooth connectivity built in include :

Printers
Scanners
Digital cameras and camcorders
Cell Phones
Headsets
PDAs
Laptops
Keyboards and Mice
In-car handsfree kits
GPS navigation receivers
Home appliances (microwaves, washers, refrigerators)

Bluetooth is becoming more widespread and functional every day reason being it is low in cost, convenient, and simple way of enabling our various computer devices to communicate to each other and to their peripherals.