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Blue Tooth
Bluetooth is an open wireless protocol for exchanging data over short distances from fixed and mobile devices, creating personal area networks (PANs). It was originally conceived as a wireless alternative to RS232 data cables. It can connect several devices, overcoming problems of synchronization.
The word Bluetooth is an anglicized version of Old Norse Blátönn or Danish Blåtand, the name of the tenth-century king Harald I of Denmark and Norway, who united dissonant Scandinavian tribes into a single kingdom. The implication is that Bluetooth does the same with communications protocols, uniting them into one universal standard.
Bluetooth uses a radio technology called frequency-hopping spread spectrum, which chops up the data being sent and transmits chunks of it on up to 79 frequencies. In its basic mode, the modulation is Gaussian frequency-shift keying (GFSK). It can achieve a gross data rate of 1 Mb/s. Bluetooth provides a way to connect and exchange information between devices such as mobile phones, telephones, laptops, personal computers, printers, Global Positioning System (GPS) receivers, digital cameras, and video game consoles through a secure, globally unlicensed Industrial, Scientific and Medical (ISM) 2.4 GHz short-range radio frequency bandwidth. The Bluetooth specifications are developed and licensed by the Bluetooth Special Interest Group (SIG). The Bluetooth SIG consists of companies in the areas of telecommunication, computing, networking, and consumer electronics.[
Bluetooth is a standard and communications protocol primarily designed for low power consumption, with a short range (power-class-dependent: 1 meter, 10 meters, 100 meters) based on low-cost transceiver microchips in each device. Bluetooth makes it possible for these devices to communicate with each other when they are in range. Because the devices use a radio (broadcast) communications system, they do not have to be in line of sight of each other.
Class 1 100 mW (20 dBm) ~100 meters
Class 2 2.5 mW (4 dBm) ~10 meters
Class 3 1 mW (0 dBm) ~1 meter
In most cases the effective range of class 2 devices is extended if they connect to a class 1 transceiver, compared to a pure class 2 network. This is accomplished by the higher sensitivity and transmission power of Class 1 devices.
More prevalent applications of Bluetooth include:
* Wireless control of and communication between a mobile phone and a hands-free headset. This was one of the earliest applications to become popular.
* Wireless networking between PCs in a confined space and where little bandwidth is required.
* Wireless communication with PC input and output devices, the most common being the mouse, keyboard and printer.
* Transfer of files, contact details, calendar appointments, and reminders between devices with OBEX.
* Replacement of traditional wired serial communications in test equipment, GPS receivers, medical equipment, bar code scanners, and traffic control devices.
* For controls where infrared was traditionally used.
* Sending small advertisements from Bluetooth-enabled advertising hoardings to other, discoverable, Bluetooth devices[citation needed].
* Two seventh-generation game consoles, Nintendo's Wii and Sony's PlayStation 3, use Bluetooth for their respective wireless controllers.
* Dial-up internet access on personal computers or PDAs using a data-capable mobile phone as a modem.
A personal computer must have a Bluetooth adapter in order to communicate with other Bluetooth devices (such as mobile phones, mice and keyboards). While some desktop computers and most recent laptops come with a built-in Bluetooth adapter, others will require an external one in the form of a dongle.
Computer requirements
Unlike its predecessor, IrDA, which requires a separate adapter for each device, Bluetooth allows multiple devices to communicate with a computer over a single adapter.
The word Bluetooth is an anglicized version of Old Norse Blátönn or Danish Blåtand, the name of the tenth-century king Harald I of Denmark and Norway, who united dissonant Scandinavian tribes into a single kingdom. The implication is that Bluetooth does the same with communications protocols, uniting them into one universal standard.
Bluetooth uses a radio technology called frequency-hopping spread spectrum, which chops up the data being sent and transmits chunks of it on up to 79 frequencies. In its basic mode, the modulation is Gaussian frequency-shift keying (GFSK). It can achieve a gross data rate of 1 Mb/s. Bluetooth provides a way to connect and exchange information between devices such as mobile phones, telephones, laptops, personal computers, printers, Global Positioning System (GPS) receivers, digital cameras, and video game consoles through a secure, globally unlicensed Industrial, Scientific and Medical (ISM) 2.4 GHz short-range radio frequency bandwidth. The Bluetooth specifications are developed and licensed by the Bluetooth Special Interest Group (SIG). The Bluetooth SIG consists of companies in the areas of telecommunication, computing, networking, and consumer electronics.[
Bluetooth is a standard and communications protocol primarily designed for low power consumption, with a short range (power-class-dependent: 1 meter, 10 meters, 100 meters) based on low-cost transceiver microchips in each device. Bluetooth makes it possible for these devices to communicate with each other when they are in range. Because the devices use a radio (broadcast) communications system, they do not have to be in line of sight of each other.
Class 1 100 mW (20 dBm) ~100 meters
Class 2 2.5 mW (4 dBm) ~10 meters
Class 3 1 mW (0 dBm) ~1 meter
In most cases the effective range of class 2 devices is extended if they connect to a class 1 transceiver, compared to a pure class 2 network. This is accomplished by the higher sensitivity and transmission power of Class 1 devices.
More prevalent applications of Bluetooth include:
* Wireless control of and communication between a mobile phone and a hands-free headset. This was one of the earliest applications to become popular.
* Wireless networking between PCs in a confined space and where little bandwidth is required.
* Wireless communication with PC input and output devices, the most common being the mouse, keyboard and printer.
* Transfer of files, contact details, calendar appointments, and reminders between devices with OBEX.
* Replacement of traditional wired serial communications in test equipment, GPS receivers, medical equipment, bar code scanners, and traffic control devices.
* For controls where infrared was traditionally used.
* Sending small advertisements from Bluetooth-enabled advertising hoardings to other, discoverable, Bluetooth devices[citation needed].
* Two seventh-generation game consoles, Nintendo's Wii and Sony's PlayStation 3, use Bluetooth for their respective wireless controllers.
* Dial-up internet access on personal computers or PDAs using a data-capable mobile phone as a modem.
A personal computer must have a Bluetooth adapter in order to communicate with other Bluetooth devices (such as mobile phones, mice and keyboards). While some desktop computers and most recent laptops come with a built-in Bluetooth adapter, others will require an external one in the form of a dongle.
Computer requirements
Unlike its predecessor, IrDA, which requires a separate adapter for each device, Bluetooth allows multiple devices to communicate with a computer over a single adapter.
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