How Bluetooth Works

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 time. This helps insure that
Bluetooth conforms to the ISM restrictions on the
transmission quantity per frequency.
2. Ensures that any interference won’t
last long. Any packet that doesn’t arrive safely
to its destination can be resent to the next
frequency.
3. Provides a base level of security as
it’s very hard for an eavesdropping device to predict
which frequency the Bluetooth devices will use
next.

The connected devices however, must agree upon the
frequency they will use next. The specification
in Bluetooth ensures this in two ways. First, it
defines a master and slave type relationship between
bluetooth devices. Next, it specifies an algorithm
that uses device specific information when
calculating the frequency hop sequences.

A Bluetooth device that operates in master mode can
communicate with up to seven devices that are set in
slave mode. To each of the slaves, the master
Bluetooth device will send its own unique address
and the value of its own internal clock. The
information sent is then used to calculate the
frequency hop sequences.

Because the master device and each of the slave
devices use the same algorithm with the same initial
input, the connected devices will always arrive
together at the next frequency that they have agreed
upon.

As a replacement for cable technology, it’s no
wonder that Bluetooth devices are usually battery
powered, such as wireless mice and battery powered
cell phones. To conserve the power, most devices
operate in low power. This helps to give Bluetooth
devices a range of around 5 – 10 meters.

This range is far enough for wireless communication
but close enough to avoid drawing too much power
from the power source of the device.

Bluetooth And Apple

The new Apple powerbook G4 are among the first
computers to offer Bluetooth technology 2.0+EDR.
The 2.0+EDR technology, which still backwards
compatible with 1.0, is up to three times faster
than previous versions, offering maximum data rate
transfers of up to 3 MBps. Being the first company
to certify a system with 2.0+EDR, Apple continues
to make great use of the Bluetooth technology.

Full support
In addition to the powerbook G4 portables, there
are other Bluetooth enabled computers available
from Apple, including the iBook, iMac G5, eMac,
and the Power Mac G5.

Making life easier
When you turn the Bluetooth feature on, your Mac
can easily perform a file transfer or even a
synchronization. From the Bluetooth selection
menu, you can choose to either send a file or
browse devices, quickly and easily. Or, you can
click the sync button in iSync to update your
cell phone or Palm OS handheld.

The Mac and GSM/GPRS mobile phone with Bluetooth
work to make each other more useful. By using
iSync, you can keep your phone updated without
having to type any info, as you can keep the
information in the more manageable address book
on your Mac instead.

You can also use your Bluetooth enabled Mac to
print documents and digital images to select a
printer that also supports the technology of
Bluetooth. Or, you can also use a headset to
talk to your friends during an iChat session.

Your Mac also has the ability to use Bluetooth
technology to communicate with your Palm OS
handheld. This way, you can perform a HotSync
operation without using any cables. You can also
send your business card or calendar events directly
to someone else’s handheld usingthe technology of
Bluetooth.

The implementation of Bluetooth by Apple is the
latest in a series of moves that have caused
great shift in the computer industry. Apple
established USB as the standard interface with
the launching of the first Mac back in 1998.

Since then, Apple established the 802.11 wireless
standard of networking with the launch of the
iBook and AirPort in 1999. During 2003, Apple
launched AirPort Extreme, which was based on
the new 802.11g high speed technology of wireless.

Now, Bluetooth helps to further strengthen the
dominant position of the Mac in wireless
communications, helping to preserve Apple’s
reputation for being the first to market with
innovative technology that integrates right into
the operating system.

Audiovox cellular phone accessory

Cellular phones have become one of the most functional modern day gadgets. It has evolved from being a luxurious toy for young professional into a necessity for the multi dimensional life of these young professionals.

However, cellular phones have different use for different people. Now, minors sport a cellular phone as a functional display, they consider it part of their wardrobe and flaunt having this modern day gadget in there complete get up. However, this is not the function of cellular phone to the business world.

They are necessities and not for dressing up. Because of the varied usefulness of cellular phones and the increasing need and want for easy communication, manufacturers are quick to take advantage of this booming industry.

Cellular phones and cellular phone accessories now flood the marketplace with different designs and different functionalities. Various cellular phone models and accessories including Audiovox cellular phone accessory comes in beautiful and functional designs.

Audiovox cellular phones and Audiovox cellular phone accessory can be such functional and comes with models that are lightweight and of beautiful designs. Audiovox cellular phone accessory such as premium power cord is a versatile power cord comes with cellular phone conditioning capacity.

Audiovox cellular phone accessory also include a hip clip holder that can be functional even when your cellular phone is not Audiovox. In addition, Audiovox cellular phone accessory such as headsets and ear glove produce a hands-free cellular phone function that will help you keep your hands on the wheels.

This will avoid accidents due to one hand driving and decreased attention on the road. Additionally, the over ear portable hands-free kit from the wide array of Audiovox cellular phone accessory line also functions to provide hands free telephony and had a built in feature that reduces background noise.

You will hear clearly the person on the other line, even while driving or doing other stuff. There is also that Jabra model of Audiovox cellular phone accessory, which is a headset that provides hands-free telephoning. Jabra is small, lighter that other headsets and stylish; it also functions as a speakerphone and thus is a more functional gadget for your cellular phone.

All these prove that Audivox cellular phone and Audiovox cellular phone accessory line are functional and technologically advance. Audiovox cellular phone accessory is a multi-functional accessory, it can function well with Audiovox cellular phone but it can also perform its functionality with other cellular phone brands.

There is also that Audiovox cellular phone accessory like the multi-functional antennae, this is attached to your car while you travel, and it functions well when you talk to another person on the other line while the car is in motion.

There are other antennas that limits their functions when you are mobile, not the antennae from the Audiovox cellular phone accessory line. This Audiovox cellular phone accessory design of antennae is very useful for travelers and corporate executives.

If you are looking for functionality in your cellular phone, try to find an Audiovox cellular phone and the matching Audiovox cellular earphone accessory for your communication requirements. They are very good for young professional who endeavor doing many things are the same time. Your Audiovox cellular phone and Audiovox cellular phone accessory line can compliment your highly active lifestyle.