2. How Radio Waves Work
Radio Waves are a way of transmitting information over millions of miles, they can transmit speech, music and other
audio. The radio waves can be only be received by tuning into the correct frequency which it is being transmitted on.
Sine waves are continuous waves which are used because the wave type can be varied to transmit different signals and
frequencies. Another reason why sine waves are used is because other devices are also using radio waves, so this way
the waves will not be confused or mixed.
Each Radio device has a two different components which make it up, these are the transmitter and the receiver.
The function of the Transmitter is to convert to original source of the media wanting to be transmitted e.g. speech
or music, into an encoded version of this media which the receiver can interpret. This is known as a sine wave
which can be transmitted into a radio wave.
The function of the Receiver is to receive the radio waves convert them into a sine wave and transfer this
information back to the original form of media being transmitted so it would be transferring the encoded wave
into the music or speech wanting to be transmitted rather than hearing the static sound which would be
transmitted otherwise.
Both the Transmitter and the Receiver both have an antenna so that they can manage the signals and pick them up or
send them out easier.
3. Frequencies
In order for Radio waves to be transmitted and received, you have to tune into a certain frequency which will let other
people who want to receive the same information as you also receive the desired information, “Radio waves have
frequencies from 300 GHz to as low as 3 kHz, and corresponding wavelengths from 1 millimeter to 100 kilometres”
[Wikipedia (2012) Radio Waves [Online]. Available from: http://en.wikipedia.org/wiki/Radio_waves. [Accessed 24/01/12].
Each radio station or broadcasting station will have their own frequency which will be unique to their station, so that
other stations wont get merged because of overlaying frequencies.
Radio waves can be transmitted from an aerial in a number of different ways either ground, sky or following the
curvature of the earth. Radio waves follow these patterns because of the reflection which they need to transmit over
long distances.
4. Aerials
Aerials are the component which receive the electrical signals which are being produced by the individual radio stations
and convert that electrical signal into the original form of media which it has been created in.
There are two main different forms of aerial either the dipole or a parabolic dish.
The dipole aerial type is made up of two metal placed either horizontally or vertically which conduct electricity.
The Parabolic Dish type of aerial works by the radio waves falling onto the dish which has a dipole in the centre of it so
the dish reflects all of the waves into the dipole which then gets forced through the transmitter which then will convert
the electrical signal into the original form of media.
Dipole aerials are used to receive television signals or very high radio signals, if the aerial is positioned straight at the
transmitter then the signal being received will be a lot stronger and clearer.
5. Wave Technology
Landline phones. These work by a signal being transmitted down a wire this signal then gets transmitted into an
electronic frequency, then the frequency will get changed into sound waves.
Mobile phones. Mobile phones use cells, cells are a radio frequency which is used in a local area. Each one will
have its own frequency and they each contain a different bas station receiver.
Television, television signals are transmitted using a transmitter which send information to the aerial and the tuner
through the means of radio waves which is using ultra high frequency. To receive this type of signal a satellite is
needed.
6. Types of Wave
Radio waves are visible waves which
carry data as a picture or sound.
Microwave are used to transmit signals
for mobile phone calls, the transmitter
and the receivers help communicate with
mobile phones that are in range
Infrared are normally used for wireless
communication, remote controls and
radio forecasting.
Ultraviolet waves are found in sunlight
and is also a visible form of wave, these
are known to change the colour of skin.
X-ray’s are used for looking at the internal
parts of the human body and bag like in
airports.
Gamma rays are used for sterilising food
and medical treatments such as cancer.
7. Importance of Radio Waves
Radio waves are massively important and have been the standing figure which has made technology progress so much
in a short amount of time. Most of us will be using radio waves in some form in day to day life without realising we are
using them, the world we live in today wouldn’t be the same technology wise if the radio wave around.
