Mobile FRC

Bluetooth devices will normally operate at 2.4 GHZ
in the license free, globally available ISM radio
band. The advantage to this band includes worldwide
availability and compatibility. A disadvantage to
this however, is that the devices must share this
band with other RF emitters. This includes
automobile security systems, other wireless devices,
and other noise sources, such as microwaves.

To overcome this challenge, Bluetooth employs a
fast frequency hopping scheme and therefore uses
shorter packets than other standards within the
ISM band. This scheme helps to make Bluetooth
communication more robust and more secure.

Frequency hopping
Frequency hopping is basically jumping from frequency
to frequency within the ISM radio band. After a
bluetooth device sends or receives a packet, it
and the device (or devices) it’s communicating with
hop to another frequency before the next packet is
sent. This scheme offers three advantages:
1. Allows Bluetooth devices to use the
entirety of the available ISM band, while never
transmitting from a fixed frequency for more than a
short period of… Read the rest

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… Read the rest

Bluetooth is a specification for the use of low
power radio communications to wireless phones,
computers, and other network wireless devices over
short distances. The name Bluetooth is actually
borrowed from Harald Bluetooth, a Denmark king
more than 1,000 years ago.

The technology of Bluetooth was primarily designed
to support simple wireless networking of devices
and peripherals, which includes cell phones, PDAs,
and wireless headsets. The wireless signals that
are transmitted by Bluetooth cover short distances
of up to 30 feet, generally communicating less
than 1 MPps (Mega Byte per second).

The networks of Bluetooth feature dynamic topology
called PAN or a piconet. The piconets contain a
minumum of two and a maximum of eight peer devices.
The devices will communicate using protocols that
are part of the specification.

Even though the Bluetooth standard will utilize
the same 2.4 GHz range as 802.11b and 802.11g,
the technology isn’t suitable for a Wi-Fi
replacement. When compared to Wi-Fi, Bluetooth
is much slower, limited in range, and actually
supports less devices.

For short range devices, Bluetooth is rapidly
becoming… Read the rest

The networking standards of Bluetooth will transmit
data via low power radio frequency. Bluetooth
communicates on a 2.45 GHz frequency. This very
band of frequency has been set aside by international
agreement for the use of industrial and medical
devices.

Many devices that you already known and use take
advantage of this frequency band. Garage door
openers, baby monitors, and the next generation of
mobile phones all use this frequency within the ISM
band. Ensuring that Bluetooth and the other
devices don’t interfere with each other is a crucial
part of the design process.

One of the ways Bluetooth will avoid interfering
with other electronic devices is by sending out
weak signals of around 1 mw. In comparison, even
the most powerful of cell phones can transmit a
signal of 3 watts.

The low power signals will limit the range of a
Bluetooth device to around 32 feet, which cut the
chances of interference between your computer and
other electronic devices. Even though it has low
power, Bluetooth doesn’t require a line of sight
between… Read the rest