2007-09-12 19:02:03 · 4 answers · asked by ainanup23 1 in Computers & Internet ➔ Hardware ➔ Add-ons
Quote:
"The Bluetooth technology was given its name in reference to the Danish king Harald "Bluetooth" Blaatand. He was the one who unified Denmark and Norway between 940 and 985 AD. The reason Bluetooth is named after him is because it is known to unite the telecom and computing industries today. "
End Quote.
Bluetooth technology has set out to replace wires used for connectivity between devices wherever possible. New laptops (mostly) come with Bluetooth technology enabled because it's possible to get a bluetooth mouse, keyboard, printer, speakers, phone etc and allow the devices to communicate wirelessly.
It functions on the wireless frequency range: 2.4 to 2.485 GHz!!
Enjoy!
2007-09-12 19:58:17 · answer #1 · answered by Beanie 3 · 0⤊ 0⤋
Origin of the name and the logo
Bluetooth was named after a late tenth century king, Harald Bluetooth King of Denmark and Norway. He is known for his unification of previously warring tribes from Denmark (including now Swedish Scania, where the Bluetooth technology was invented), and Norway. Bluetooth likewise was intended to unify different technologies, such as computers and mobile phones.
The name may have been inspired less by the historical Harald than the loose interpretation of him in The Long Ships by Frans Gunnar Bengtsson, a Swedish Viking-inspired novel.
The Bluetooth logo merges the Nordic runes analogous to the modern Latin H and B: hagall and bjarkan from the Younger Futhark runes forming a bind rune.
How Bluetooth Technology Works
Bluetooth wireless technology is a short-range communications system intended to replace the cables connecting portable and/or fixed electronic devices. The key features of Bluetooth wireless technology are robustness, low power, and low cost. Many features of the core specification are optional, allowing product differentiation.
The Bluetooth core system consists of an RF transceiver, baseband, and protocol stack. The system offers services that enable the connection of devices and the exchange of a variety of data classes between these devices.
Overview of Operation
The Bluetooth RF (physical layer) operates in the unlicensed ISM band at 2.4GHz. The system employs a frequency hop transceiver to combat interference and fading, and provides many FHSS carriers. RF operation uses a shaped, binary frequency modulation to minimize transceiver complexity. The symbol
rate is 1 Megasymbol per second (Msps) supporting the bit rate of 1 Megabit per second (Mbps) or, with Enhanced Data Rate, a gross air bit rate of 2 or 3Mb/s. These modes are known as Basic Rate and Enhanced Data Rate respectively.
During typical operation, a physical radio channel is shared by a group of devices that are synchronized to a common clock and frequency hopping pattern. One device provides the synchronization reference and is known as the master. All other devices are known as slaves. A group of devices synchronized in this fashion form a piconet. This is the fundamental form of communication for Bluetooth wireless technology.
Devices in a piconet use a specific frequency hopping pattern which is algorithmically determined by certain fields in the Bluetooth specification address and clock of the master. The basic hopping pattern is a pseudo-random ordering of the 79 frequencies in the ISM band. The hopping pattern may be adapted to exclude a portion of the frequencies that are used by interfering devices. The adaptive hopping technique improves Bluetooth technology co-existence with static (non-hopping) ISM systems when these are co-located.
The physical channel is sub-divided into time units known as slots. Data is transmitted between Bluetooth enabled devices in packets that are positioned in these slots. When circumstances permit, a number of consecutive slots may be allocated to a single packet. Frequency hopping takes place between the transmission or reception of packets. Bluetooth technology provides the effect of full duplex transmission through the use of a time-division duplex (TDD) scheme.
Above the physical channel there is a layering of links and channels and associated control protocols. The hierarchy of channels and links from the physical channel upwards is physical channel, physical link, logical transport, logical link and L2CAP channel.
Within a physical channel, a physical link is formed between any two devices that transmit packets in either direction between them. In a piconet physical channel there are restrictions on which devices may form a physical link. There is a physical link between each slave and the master. Physical links are not formed directly between the slaves in a piconet.
The physical link is used as a transport for one or more logical links that support unicast synchronous, asynchronous and isochronous traffic, and broadcast traffic. Traffic on logical links is multiplexed onto the physical link by occupying slots assigned by a scheduling function in the resource manager.
A control protocol for the baseband and physical layers is carried over logical links in addition to user data. This is the link manager protocol (LMP). Devices that are active in a piconet have a default asynchronous connection-oriented logical transport that is used to transport the LMP protocol signaling. For historical reasons this is known as the ACL logical transport. The default ACL logical transport is the one that is created whenever a device joins a piconet. Additional logical transports may be created to transport synchronous data streams when this is required.
The link manager function uses LMP to control the operation of devices in the piconet and provide services to manage the lower architectural layers (radio layer and baseband layer). The LMP protocol is only carried on the default ACL logical transport and the default broadcast logical transport.
Above the baseband layer the L2CAP layer provides a channel-based abstraction to applications and services. It carries out segmentation and reassembly of application data and multiplexing and de-multiplexing of multiple channels over a shared logical link. L2CAP has a protocol control channel that is carried over the default ACL logical transport. Application data submitted to the L2CAP protocol may be carried on any logical link that supports the L2CAP protocol.
2007-09-13 03:04:34 · answer #2 · answered by sagarukin 4 · 0⤊ 0⤋
man whats with the cut and paste
2007-09-13 21:50:00 · answer #3 · answered by Anonymous · 0⤊ 0⤋
Beanie got it right..
:)
2007-09-13 10:33:21 · answer #4 · answered by Sridhar G 6 · 0⤊ 0⤋