Bluetooth

Introduction

Bluetooth is a radio technology making transmission of signals over short distances between cell phones, computers and other devices, like household appliances, without the use of wires. The name Bluetooth was born from the 10th century king of Denmark, King Harold Bluetooth who engaged in diplomacy which led warring parties to negotiate with each other. The inventors of the Bluetooth technology thought this a fitting name for their technology which allowed different devices to talk to each other.

Benefit

Bluetooth technology is based on communications central to other devices. Fundamentally, Bluetooth operates within the Industrial, Scientific and Medical (ISM) band at 2.4 GHz. It is a short-range wireless communication standard defined as cable replacement for a Personal Area Network (PAN).

A cable replacement standard has been defined because cables limit mobility of the consumer; they are hard to carry out, are easily lost or broken. To counteract these limitations Bluetooth is designed to be light and portable. It includes standards and protocols to make it mobile, robust, reliable and not limited to other Bluetooth devices.

Classes

Bluetooth is a radio standard primarily designed for low power consumption, with a short range (power class dependent: 1meter, 10 meters, 100 meters) and with a low-cost transceiver microchip in each device. Bluetooth lets these devices talk to each other when they come in range, even if they are not in the same room, as long as they are within up to 100 meters of each other, dependent on the power class of the product.

Costs

The costs of Bluetooth may from $5 to $20. It depends on its material, distance range, and feature. For example, the Class 1 Bluetooth chip got longer distance range and stronger signal then Class 3 chip so it costs more then class 3

Class Power Power Range Costs

(mW) (dBm) (approximate)

Class1 100 mw 20 dBm 100 meters $20

class2 2.5 mw 4dBm 10meters $15

class3 1mw 1dbm 1 meter $5

Important

Nowadays date communication become more and more important. The characteristic of Bluetooth such as Cable replacement between devices, Supported by major companies, Open Specification, Low power consumption, Connection can be initiated without user interaction, and devices can be connected to multiple devices at the same time. Bluetooth technology

become more and more popual in our daily life, using Bluetooth earphone instead with handing cell phone while you are driving. It is more safe for drving. Using bluetooth devices to exchange personal information with others. It helps people get correct and fact date. Bluetooth provides interoperability between devices from different manufacturers for specific services and use cases.

Implemented

Since Ericsson stared Bluetooth protocol not only implements on cell phone but also on many way such as on computer industry, Bluetooth has already been implemented on printers, mouse and keyboards. Bluetooth cell phones have been sold in large numbers, and are able to connect to computers, personal digital assistants (PDAs), certain automobile handsfree systems and various other devices. The standard also includes support for more powerful, longer-range devices suitable for constructing wireless LANs.

Originally, Bluetooth was designed for a cable replacement but Bluetooth has evolved to become an infrastructure