1. Radio waves!
By Henry Lau
Media Production TECH 1002
Studies in Media Technology 1
2. What are they?
Radio waves are simply wavelengths made from
electromagnetic radiation which are part of the
electromagnetic spectrum. They were put into the
group based off its frequency and its constant
wavelength. This means there are several others
which were grouped together to create the whole
electromagnetic spectrum. Several examples
include:
Gamma radiation
X-ray radiation
Ultraviolet radiation
Visible radiation
Microwave radiation
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3. Why do we use them?
We mainly use them to
carry across (transmit)
long distance
information. It is
currently the most
efficient method next to
the internet. It can range
from basic Morse code to
voice to voice
communication.
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4. Why are they important?
During our everyday lives most of us rely on
the use radio waves whether we realise it or
not. Despite this radio waves are constantly
being used to transmit information across the
whole world. Its used as the base for most
wireless communication and invisible hence
why we’re mostly unaware when we’re using
it. Without radio waves the majority of our
communication devices wouldn't’ work
including mobile phones, radio broadcasting
stations and even television!
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5. What uses radio waves?
Television signals
Wireless internet
Radio stations
Mobile phones
Garage door openers
Police radios
GPS devices
Wireless clocks
Etc…
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6. Wi-Fi
Wireless network or Wi-Fi is exactly what It sounds like, wireless
internet which can be used almost everywhere. Quite often, their
services (sometimes free) are provided in several hotspots such as
cafes, libraries and hotels.
Wi-Fi also uses radio waves, similar to how radios have a two way
communication.
The process starts by the device (laptop/mobile) translating data
into a radio wave and sends it to router through the access point.
the router then sends the information to the internet through a
wired connection. With the information received the process goes in
reverse till the original device obtains that information.
Wi-Fi uses frequencies ranging from 2.4GHz to 5GHz, this is
considered higher than usual frequencies due to the devices
requiring more information than say a television or walkie-talkie.
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7. Television
Televisions are used almost everyday by everyone, whether it
being for casual entertainment or watching the news, it plays
a huge part in our lives today.
The process starts by mixing 2 electrical signals, one from a
microphone for sound and one from a video camera. This is
called Modulation. The audio uses Amplitude Modulation (AM)
and the images uses the Frequency Modulation (FM). The TV
antenna then picks up the carrier wave and then re converts
the signal back into the original format allowing us to see
what we would usually expect on the screen. This is known
as demodulation.
The frequency used for television ranges from around
470MHz to 865MHz.
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8. Mobile Phones
Mobile phones in this generation, is probably the most important piece of
technology we’ve ever used so much in our lives, around 60% of the UK
population use mobile phones today.
The mobile phone works through using radio waves, transmitting and
receiving information such as computer data, speech and so much more.
The mobile first sends frequency signals from the nearest base station, with
this the signal then gets transmitted to the main telephone network through
cables or a different frequency (usually higher than the original) on an
antenna. At the main network, the network finds the specific mobile and
sends the signal to it in reverse through another base station which covers
where the mobile is currently in. depending on the mobile’s status the
second mobile sends back information the original phone instantly, this
constantly occurs till the communication with each device ends through user
input or loss of signal.
Mobile phones services operate in several frequencies ranging from 872 to
960 MHz, 1710 to 1875 MHz and 1920 to 2170 MHZ.
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9. Bibliography
How Do WiFi Wireless Networks Work. 2012. How Do WiFi Wireless Networks Work. [ONLINE]
Available at: http://www.pool-king.com/wireless/wireless-networks.php. [Accessed 29 January 2012].
HowStuffWorks "What Is WiFi?". 2012. HowStuffWorks "What Is WiFi?". [ONLINE] Available at:
http://computer.howstuffworks.com/wireless-network1.htm. [Accessed 29 January 2012].
HowStuffWorks "How Radio Works". 2012. HowStuffWorks "How Radio Works". [ONLINE] Available at:
http://electronics.howstuffworks.com/radio4.htm. [Accessed 29 January 2012].
What are radio waves?. 2012. What are radio waves?. [ONLINE] Available at:
http://www.qrg.northwestern.edu/projects/vss/docs/communications/1-what-are-radio-waves.html.
[Accessed 29 January 2012].
Radio and Television. 2012. Radio and Television. [ONLINE] Available at:
http://www.scribd.com/doc/1028/Radio-and-Television. [Accessed 30 January 2012].
Mobile Phone Base Stations - How Mobile Phone Networks Work. 2012. Mobile Phone Base Stations -
How Mobile Phone Networks Work. [ONLINE] Available at:
http://www.ofcom.org.uk/static/archive/ra/topics/mpsafety/school-audit/mobilework.htm. [Accessed
30 January 2012].
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10. Bibliography continued
TV Channels and Frequency Bands. 2012. TV Channels and Frequency Bands. [ONLINE] Available at:
http://www.gbaudio.co.uk/atchannels.pdf. [Accessed 30 January 2012].
tv vector - eps, ai, cdr, svg, pdf. 2012. tv vector - eps, ai, cdr, svg, pdf. [ONLINE] Available at:
http://tvvector.blogspot.com/. [Accessed 30 January 2012].
TomTom Language Bug | XarJ Blog and Podcast. 2012. TomTom Language Bug | XarJ Blog and
Podcast. [ONLINE] Available at: http://www.xarj.net/2008/tomtom-language-bug/. [Accessed 30
January 2012].
Bodet Time solutions that work for you. 2012. Wireless clock system. [ONLINE] Available at:
http://www.bodet.co.uk/clock-systems/select-a-technology/wireless-clock-system.html. [Accessed 30
January 2012].
Mobile Phone Style Vector Icon | Free Icon | All Free Web Resources for Designer - Web Design Hot!.
2012. Mobile Phone Style Vector Icon | Free Icon | All Free Web Resources for Designer - Web Design
Hot!. [ONLINE] Available at: http://www.webdesignhot.com/free-icon/mobile-phone-style-vector-
icon/. [Accessed 30 January 2012].
The Electromagnetic Spectrum: Home page . 2012. The Electromagnetic Spectrum: Home page .
[ONLINE] Available at: http://www.darvill.clara.net/emag/index.htm. [Accessed 30 January 2012].
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