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Bluetooth
Overview
| The
Bluetooth wireless technology is set to revolutionize the personal
connectivity market by providing freedom from wired connections. It is a
specification for a small form-factor, low-cost radio solution providing
links between mobile computers, mobile phones and other portable handheld
devices, and connectivity to the internet. |
| The
Bluetooth Special Interest Group (SIG), comprised of leaders in the
telecommunications, computing, and network industries, is driving
development of the technology and bringing it to market. The Bluetooth SIG
includes promoter companies 3Com, Ericsson, IBM, Intel, Lucent, Microsoft,
Motorola, Nokia and Toshiba, and thousands of adopters |
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Technology
Bluetooth is a global de facto standard for wireless connectivity. Based
on a low-cost, short-range radio link, Bluetooth cuts the cords that used
to tie up digital devices.
When two Bluetooth equipped devices come within 10 meters range of each
other, they can establish a connection together. And because Bluetooth
utilizes a radio-based link, it doesn't require a line-of-sight connection
in order to communicate. Your laptop could send information to a printer
in the next room, or your microwave could send a message to your mobile
phone telling you that your meal is ready. |
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In the
future, Bluetooth is likely to be standard in tens of millions of mobile
phones, PCs, laptops and a whole range of other electronic devices. As a
result, the market is going to demand new innovative applications,
value-added services, end-to-end solutions and much more. The
possibilities opened up really are limitless, and because the radio
frequency used is globally available, Bluetooth can offer fast and secure
access to |
| wireless
connectivity all over the world. With potential like that, it's no wonder
that Bluetooth is set to become the fastest adopted technology in history. |
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Bluetooth wireless technology is a system
solution comprising hardware, software and interoperability requirements.
The Bluetooth specifications specify the complete system.
The Bluetooth Specification defines a short (around 10 m) or optionally a
medium range (around 100 m) radio link capable of voice or data
transmission up to a maximum capacity of 720 Kb/s per channel. |
Radio
frequency operation is in the unlicensed industrial, scientific and
medical (ISM) band at 2.4 to 2.48 GHz, using a spread spectrum, frequency
hopping, full-duplex signal at up to 1600 hops/sec. The signal hops among
79 frequencies at 1 MHz intervals to give a high degree of interference
immunity. RF output is specified as 0 dBm (1 mW) in the 10m-range version
and -30 to +20 dBm (100 mW) in the longer range version.
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| When
producing the radio specification, high emphasis was put on making a
design enabling single-chip implementation in CMOS circuits, thereby
reducing cost, power consumption and the chip size required for
implementation in mobile devices. |
| The
Bluetooth Solution answers the need for short-range wireless connectivity
within three areas:
Data and Voice access points
Cable replacement
Ad hoc networking
Data and Voice access points
Bluetooth wireless technology facilitates real-time voice and data
transmissions, which makes it possible to connect any portable and
stationary communication device as easily as switching on the lights.
You can, for instance, surf the Internet and send e-mails on your portable
PC or notebook regardless of whether you are wirelessly connected through
a mobile phone or through a wire-bound connection (PSTN, ISDN, LAN, xDSL). |
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Voice
Up to three simultaneous synchronous voice channels are used, or a channel
which simultaneously supports asynchronous data and synchronous voice.
Each voice channel supports a 64 kb/s synchronous (voice) channel in each
direction.
Data
The asynchronous data channel can support maximal 723.2 kb/s asymmetric
(and still up to 57.6 kb/s in the return direction), or 433.9 kb/s
symmetric.
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Cable
replacement
Bluetooth wireless technology eliminates the need for numerous, often
proprietary, cable attachments for connection of practically any kind of
communication device.
Connections are instant and they are maintained even when devices are not
within line of sight. The range of each radio is approximately 10 meters,
but it can be extended to around 100 meters with an optional amplifier.
Ad hoc networking
A device equipped with a Bluetooth radio establishes instant connection to
another Bluetooth radio as soon as it comes into range.
Since each Bluetooth device supports both point-to-point and
point-to-multipoint connections, several piconets can be established and
linked together ad hoc. The Bluetooth topology is best described as a
multiple piconet structure.
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Related Readings
Bluetooth
GSM
GPRS
3G
WAP
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