Bluetooth Technical Operations

Bluetooth Technical Operations

Bluetooth is a high speed, low powered wireless link
technology that's designed to connect phones or other
portable equipment together with little to no work
required by the user. Unlike infrared, Bluetooth
doesn't require line of site positioning to work.

Current prototype circuits are contained on a board
that is 0.9 cm square, with a much smaller circuit
board being developed.

When one Bluetooth device comes in contact with
another, they will automatically exchange addresses
and details of capability. Then, they can establish
a 1 MB link with security that they will use as
required. The protocols involved with handle both
data and voice, with a very flexible topography.

The technology achieves its goal by embedding tiny,
non expensive short range tranceivers into the
devices available today. The radio operates on the
2.45 GHz frequency band, and supports up to 721
KBps, along with three voice channels.

Each devices offers a unique 48 bit address from
the IEEE 802 standard, with the connections being
point to point or multipoint. The max range is
10 meters, although it can be extended to 100
meters by increasing the power. The devices are
also protected from radio interference by changing
their frequencies, also known as frequency hopping.

What's important, is the fact that Bluetooth
devices won't drain battery life. The specification
targets power consumption of the device, limiting
the drain on the battery. The radio chip will
consume only 0.3mA in stand by mode, which is less
than 5% of the power that standard phones use.

Bluetooth will also guarantee security at the bit
level. The authentification is controlled by the
user via a 128 bit key. The radio signals can
be coded with anything up to 128 bit. With the
frequency hopping, Bluetooth is already very
hard to listen into.

The baseband protocol is a combination of both
circuit and packet switches. Slots can be reserved
for synchronous packets as well. Each packet
will be transmitted in a different hop frequency.
Normally, a packet covers a single slot although
it can be extended to cover up to five slots.

Bluetooth can also support data channels of up to
three simultaneous voice channels. Therefore,
it's possible to transfer the data while you talk
at the same time. Each individual voice channel
will support 64 KB.

From a technical standpoint, Bluetooth is very
different indeed. It's the best wireless method
in the world, surpassing even infrared. For
communication on the go, Bluetooth is indeed
very hard to compete with.

Advantages And Disadvantages

Bluetooth has a lot to offer with an increasingly
difficult market place. Bluetooth helps to bring
with it the promise of freedom from the cables and
simplicity in networking that has yet to be matched
by LAN (Local Area Network).

In the key marketplace, of wireless and handheld
devices, the closest competitor to Bluetooth is
infrared. Infrared holds many key features,
although the line of sight it provides doesn't go
through walls or through obstacles like that of the
Bluetooth technology.

Unlike infrared, Bluetooth isn't a line of sight and
it provides ranges of up to 100 meters. Bluetooth
is also low power and low processing with an
overhead protocol. What this means, is that it's
ideal for integration into small battery powered
devices. To put it short, the applications with
Bluetooth are virtually endless.

Disadvantages
Bluetooth has several positive features and one
would be extremely hard pressed to find downsides
when given the current competition. The only real
downsides are the data rate and security. Infrared
can have data rates of up to 4 MBps, which provides
very fast rates for data transfer, while Bluetooth
only offers 1 MBps.

For this very reason, infrared has yet to be
dispensed with completely and is considered by
many to be the complimentary technology to that
of Bluetooth. Infrared has inherent security due
to its line of sight.

The greater range and radio frequency (RF) of
Bluetooth make it much more open to interception and
attack. For this reason, security is a very key
aspect to the Bluetooth specification.

Although there are very few disadvantages, Bluetooth
still remains the best for short range wireless
technology. Those who have tried it love it, and
they know for a fact that Bluetooth will be
around for years to come.