The use and importance of radio waves and signals beyond radio broadcasting

2.  Radio waves are part of a larger family of
waves on the electromagnetic spectrum.
 They have the longest wave length in the
electromagnetic spectrum and can range
from 1 millimetre to hundreds of metres.
 Radio waves have frequencies varying from
as low as 3 kHz up to 300 GHz.
 They are used for various different forms of
communication.

3. This diagram shows radio waves on the electromagnetic spectrum. It shows
the length of the wavelengths for different devices that use radio waves
with radar, television, FM and AM waves. It shows that radio waves not only
have the largest wavelength in the electromagnetic spectrum, they also
have the biggest range in wave size in the spectrum.
Radio waves cannot be seen as they lie outside of the visible light section in
the electromagnetic spectrum.

4.  Radio waves are very important in everyday
life.
 They are used for nearly all non-written
communication and most wireless
technologies.
 Radio waves transmit
music, conversations, pictures and data
invisibly through the air, often over vast
distances.
 Many common household products require
radio waves to work. AM and FM
radios, wireless networks, telephones and
televisions all require radio waves to operate.

5.  AM and FM radio broadcasts
 Cordless phones
 Radar
 Garage door openers
 Wireless networks
 Radio-controlled toys
 Television broadcasts
 Mobile phones
 GPS receivers
 Satellite communications
 Police radios
 Wireless clocks

6.  Many people use wireless
networking, also known
as WiFi, to connect to the
internet via their
computers, laptops or
mobile phones.
 It makes internet
connecting more
convenient because it
doesn’t require wires or
cables and therefore
allows for roaming.

7.  WiFi transmits at frequencies of 2.4 GHz or 5
GHz which is considerably higher than many
other devices that use radio waves. This allows
the signal to carry more data, allowing for a
better internet connection.
 Wireless radio waves can transmit on three
different frequency bands or, they can
“frequency hop”, switching between all three
bandwidths. This helps to reduce interference
and allows multiple devices to use the same
wireless connection simultaneously.

8.  A radar system emits radio
waves, called radar signals, in
predetermined directions
through a transmitter. When
the signals come into contact
with an object they are
reflected and/or scattered
into different directions. The
signals that are reflected
back towards the transmitter
are the desirable ones which
make the radar work, making
the object visible on the
radar.

9.  Radar is used in a variety of ways, for example: to
detect a moving object in the distance; to
detect the speed of an object; or to map
something.
 Police use it to detect speeding motorists.
 Planes, both in the air and on land, can be
detected via radar and air traffic controllers use
it to guide safe landings.
 The military use radar to detect the enemy and
to guide weapons.
 NASA use radar to map the Earth and other
planets as well as tracking satellites.
 Meteorologists can use radar to track
storms, hurricanes and tornadoes.

10.  http://en.wikipedia.org/wiki/Radio_waves
 http://www.antonine-
education.co.uk/physics_gcse/Unit_1/Topic_5/topic_5_wh
at_are_the_uses_and_ha.htm
 http://passion4science.wordpress.com/2011/08/06/electro
magnetic-spectrum/
 http://curiosity.discovery.com/question/what-importance-
of-radio-waves
 http://en.wikipedia.org/wiki/Radio_waves#Radio_commu
nication
 http://computer.howstuffworks.com/wireless-network.htm
 http://en.wikipedia.org/wiki/Radar
 http://science.howstuffworks.com/radar.htm
 https://marketplace.secondlife.com/ja-JP/p/AWDesigns-
Radar-V12-BOX-PROMO/1758892?id=1758892&lang=ja-
JP&locale=ja-JP&slug=AWDesigns-Radar-V12-BOX-PROMO