Here is my presentation on the importance and uses of radio waves.

2. Radio Waves are essentially invisible signals that can be received by various different
devices. Radio waves are one of the longest wavelengths in the electromagnetic
spectrum and have a whole variety of uses other than allowing you to listen to music
on the radio. The recent advances in technology have meant that radio signals can
now be detected by mobile phones, television sets and online.
Heinrich Hertz proved the existence of radio waves in 1880 and since this discovery the
technology has dramatically advanced as our understanding of how radio waves
work has increased. It is possible to tune your radio to a specific frequency so that
you can receive certain radio broadcasts, however not all are available everywhere.
A small radio station like Demon FM will only be accessible within about 10 miles of
DMU whereas a much larger station like Radio 1 will be available over a much larger
area.
The ionosphere can be found in the earths atmosphere and can allow radio waves to
travel much larger distances at night. This is possible because at night radio waves
can reflect off the ionosphere and bounce to and from earth meaning they can travel
much further. This can sometimes mean stations that you would not normally be able
to receive from your home are accessible at night.

3. Radio waves play a huge role in everyday life, however many people do not realise how
much we depend on them. Probably the most important use of radio signals is
communication, as they have dramatically changed the way we communicate with
each other in day to day life. A prime example would be the mobile phone, as most
people own a mobile phone that uses radio waves to send and receive messages. In
addition to this radio waves are also used to operate essential radio systems for
planes, satellite navigation systems and police radio’s, which is continually improving
our way of life and playing a majorly important part in society today.
Without the use of radio waves technology would not have advanced as quickly as it has
recently. The common use of radio waves has allowed us to communicate with one
another much more efficiently and over huge distances. The ability to send files,
pictures and music to one another has meant that a lot of media has been shared
around at a much faster pace, an example being viral videos or breaking news.
This technology is not only important socially but also for military reasons, as satellites and
radio systems are used to communicate on the battlefield. The army, air force and
navy all use radio waves in some aspect of their technology to communicate with
one another, which can in turn save lives. With the continuing development of
technology radio waves are surely going to be incorporated in to another useful item
or communication method that will improve our lives once more.

4. Mobile Phones are one of the main devices that depend on
radio waves to operate and are commonly used all over
the world. In order for mobiles to work a telephone
network is needed. Radio base stations provide this
service by transmitting signals from an antenna to
mobiles so that messages can be sent and received.
Mobile networks are split up in to ‘cells’ that each have a
base station. The major cities usually have smaller cells
as each base station is having to cope with large
numbers of calls because of the dense population. This
is completely different to the countryside where one cell
may be used for a much larger area.
In order for a call to be made from one mobile to another a
radio base station is required. This is more informally
known as having ‘signal’ and the closer you are to one of
these stations the better your signal. To make a call the
mobile will send radio signals to a base station, which
will then send a signal to the nearest base station of the
person receiving the call. This signal will then be sent to
the phone of the person being called so they can receive
the incoming call. Whilst on the move in a car or on a
train the base station will switch as you move from cell to
cell to avoid cutting you off mid conversation.

5. Radio waves are also used in another huge medium,
television. Millions of people watch television everyday
so it’s a big business with very high demand for
channels and cable T.V. This means that thousands of
T.V stations are required to satisfy this demand and
broadcast the radio waves that are used to transport the
signal to peoples homes. The radio waves will carry
signals that are transmitted from the stations to your T.V
set antenna, which will then be displayed on the screen
in the form of an image made up of pixels. There are
multiple channels available in the modern day so this
shows how much we have advanced since T.V was first
invented.
Cable companies provide most of the channels by using
satellite dishes and antennas to receive the T.V stations
transmissions, which they then sell to customers for the
luxury of being able to view the channel in their home.
Television signals are transmitted using Ultra high
frequency, which is approximately 470 – 582MHz. In
order to receive this television signal you need a satellite
dish that will pick up the radio waves broadcast from T.V
stations and convert the information in to an image on
your T.V screen.

6. WiFi is a reasonably new technology that has made it possible
to use radio waves to produce high speed wireless
internet. This internet connection is produced by sending
a radio signal from a computer antenna to a wireless
router which is designed to convert this information in to
an internet connection. Once the router has converted the
signal to a connection it is sent to the computer using an
Ethernet cable so the user can connect to the internet.
WiFi is also used for radio communication because of its
high frequency which allows more data to be transmitted.
These WiFi radios transmit at a frequency of 2.4 GHz or 5
GHz which is significantly higher than that of other
technologies that use radio waves.
WiFi is now widely used because of its convenience and
simplicity and is common in most households. The use of
radio waves allows multiple people to access the same
wireless router at once, however if too many people use
the network at once then its possible to lose connection.

7. The military use radio waves for a variety of important
tasks that are extremely helpful in a war
situation. The radar is the first example of the
military exploiting this useful technology. The
radar was first used in World War 2 and uses
radio waves to locate objects and provide
certain details about them. These details can be
extremely valuable and provide information on
how far away the object is from the transmitter,
how fast the object is going and even the height.
This is particularly useful for detecting missiles
and other enemy forces that may be close by,
which gives some warning as to when an attack
might happen or where enemies may be hiding.
In order to locate objects radio waves are
transmitted, which will then reflect back off
anything it encounters. The reflected waves will
then be received by the antenna which will
display the object on a screen or monitor. This
allows the military to pin point the locations of
certain objects whether they are in the air, in
space or on the ground. This technology is used
in multiple devices by the military ranging from
marine radars to antimissile defence systems.

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