A presentation exploring a few different ways radio waves are used in media technology other than traditional radio broadcasting.

1. Radio Waves and their uses in
Media Technology
Cat Riley
P11258060

2. Radio Waves
This presentation will explore alternative uses for radio waves outside of
traditional radio broadcasting.
Radio waves are the lowest frequencies in the electromagnetic spectrum, and
are used mainly for communications. They are created and sent round via
transmitters. Stars, other gases in space, and lightening also emit radio
waves. This is why interference is sometimes heard when listening to the
radio during a storm.

3. Just Radio?
Radio waves are used to transmit information from one
destination to another through the air or some cases space.
This does not mean just for the purpose of radio stations
broadcasting to listeners; there are other important uses
within the media field.
 To transmit television signals
 To allow people to communicate via telephone
without being plugged into a landline
 To access the internet wirelessly and on the move
 To send and receive data through wireless pairing
via bluetooth
 Etc…

4. Bluetooth
This widely used communication system was named after Harald Bluetooth, a
famous Danish king who introduced Christianity and united Denmark and
part of Norway into a single kingdom. This reference was chosen for the
name as a nod towards the Nordic region and how important its
companies have been in the development of the communications
industry.
Bluetooth transmits data via very low frequency
(between 2.402 and 2.480 gigahertz) radio waves.
This band is know as the ISM (industrial, scienctific,
medical). Baby monitors, mechanical garage doors
and cordless phones also use this waveband.
Bluetooth devices send extremely weak signals
(about 1 milliwat) so as not to interfere with other
devices. For example a poweful mobile phone which
can transmit at around 3 milliwats.
Click here for a useful video on the basics of Bluetooth

5. Bluetooth
Example: The notification when sending a file
from my mobile phone to my laptop.
When devices that are both Bluetooth capable (such as a mobile phone and a
headset as shown above) are in range, an automatic conversation occurs
to decided whether they have data that needs sharing. Both devices then
hop between frequencies within the ISM band so they can stay together
and avoid any other piconnets, otherwise known as PANs or Personal Area
Networks, that may be operating in the immediate area.
With bluetooth, many different kind of data can be sent and receieved,
depending on the type of devices that are connecting.

6. Wi-Fi
Wireless networks are everywhere. Free wi-fi is commonly provided in public
places such as cafes, airports libraries and on trains. These networks allow
people to access the world wide web on their portable devices whenever
they want, without the use of cables or wires.
A wireless internet connection is comparable to a
two-way radio communication. Data is
translated into a radio signal and is
transmitted using an antennae by
the computer’s wireless router.
This signal is then decoded by the
wireless router, which sends the
information to the internet using
an Ethernet connection (a physical wire).
Click here for a quick video explanation of Wi-fi

7. Wi-Fi
Wi-fitransmits at a frequency of either 2.4 or 5 gigahertz, significantly higher
than Bluetooth, mobile phones or televisons. A higher frequency enables
the signal to carry more data.
Wi-fi connections use 802.11 networking standards, which come in a few
different varieties, transmitting at different speeds and able to handle
different amounts of data:
802.11a –
5 GHz, 54 megabits per second
802.11b –
2.4 GHz, 11 megabits per second
802.11g –
2.4 GHz, 54 megabits per second
802.11n –
5 GHz, 24 megabits per second
(but reportedly can achieve 140)

8. Bibliography
• NASA’s Imagine the Universe!
http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html
• Electromagnetic Spectrum image
http://lot.astro.utoronto.ca/images/spectrum.png
• Infoplease
http://www.infoplease.com/ce6/sci/A0860617.html
• How Stuff Works
http://electronics.howstuffworks.com/bluetooth1.htm
http://computer.howstuffworks.com/wireless-network1.htm
• Bluetooth Logo Image
http://www.ketrin.co.uk/wp-
content/blog/uploads/2011/05/BlueTooth.png

9. Bibliography continued…
• Womanwith headset image
http://2.bp.blogspot.com/_Qv8wb7pq08Q/TTwB7zsu2ZI/AAAAAAAAAlY/h
OahyuY7lLg/s1600/Best_Bluetooth_Headsets.jpg
• Wi-Fi logo image
http://www.annectocomputers.co.uk/wp-content/uploads/2011/07/Wi-
FI-Converted-copy.gif
• How Wi-Fi works image
http://static.ddmcdn.com/gif/wireless-network-1a.jpg
• Youtube
http://www.youtube.com/watch?v=e1p4c7Gf8d8&feature=related
• E How
http://www.ehow.com/video_4754178_wifi-work.html