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.
(word count 450)
Terms of Use for this Private Label Article
Possibly Related PLR Articles:
Empress Hotel
Located in the heart of the charming La Jolla village,
the Empress Hotel is an enchanted palace located
just four miles north of Mission Bay. Adding a
little bit more beauty to the already amazing San
Diego, this hotel is very popular for...read more
Betting Using Horse Racing Selection Systems
Since then, horse racing has been a part of our society. It has been a popular entertainment for many different people. Although many people think that it's impossible to make money by betting on horse racing, other finds it quite profitable using...read more
Dress Santa Game
If you are willing to put a little time and energy into a Christmas game, this one is surefire hit. It's called "dress Santa" and it's funny and silly and worth having a camera round to record the fun. You might even want a camcorder as well.
...read more
Finding Low-Cost Air Purifiers
Are you interesting in purchasing an air purifier? A large number of individuals are. Unfortunately, many mistakenly believe that they cannot afford an air purifier. While air purifiers, at least a good portion of them, can be considered...read more
Internet Security Software: Free Downloads To Secure Your PC
The internet is considered as the information superhighway where you can gather the information you need for school and work. In fact, the internet is so useful that people have begun to use it for businesses.
The internet can even be a great...read more
Information Detective
Vital Information
-------------------------------------------------------------------------------
Start-up Investment
Low - $5000 ( a home office)
High - $20,000 (an office with one employee)
...read more
PPC Appraisal Program: Leave Your Computer On And Earn Money
This program is very simple to download, entirely free and really works!
Requiring no sponsoring, no costs at all to join, once it has been set up, the only thing you do is leave your computer on and the system will just automatically run and...read more
Green drinks and the pH miracle diet
If you've been learning about the benefits of the pH miracle diet you've probably run across the phrase "green drinks" before. In fact, a quick search of reviews on Robert Young's book "The pH Miracle Diet" shows that many people who use the program...read more
Advantages and Disadvantages of Purchasing Your Own Affiliate Tracking Software
Millions of business owners rely on affiliate programs to help increase their sales and in turn their profits. If are the owner of an online business, especially one that sells a particular product or service, you may be able to benefit from the use...read more
Building Your Business with an Opt-in List
Before revealing the secrets of the trades, here are myths and fallacies that need to be cleared before one indulges into building an opt-in list. These marketing misconceptions could pose so much of an obstacle towards your profitting well from...read more