2. One of the most commonly accepted uses of
radio waves is in the radio that most people
listen to everyday.
However the use of radio waves is much more
widespread than that, and also much more
varied
In this presentation a few of these uses and
methods will be investigated in more detail.
3. Radio waves make up one end of the electromagnetic spectrum.
They have the longest wavelength (up to 100km) compared other
types, such as infrared or microwaves.
As such, they are suited for transmitting signals over long
distances, for purposes of communication between transmitter
and receiver.
Radio waves on the
electromagnetic
spectrum
5. These are networks of interconnected computers or
mobile devices which, as the name suggests, do not
require wires or cables to communicate with one
another.
Instead these networks generally use radio waves to
send signals to each other.
There are various types of wireless networks, most
depending on the size of the network created.
The implementation of wireless networks has had a
visible impact on the world we live in, with almost all
electronic devices released in recent years having had
some form of wireless connectivity in-built.
The public has grown increasingly dependent on
wireless networking with 98% of people who responded
to some connection-based surveys stating that they use
Wi-Fi daily, with many expecting it to be built into a
device that they purchase (Devicescape 2011).
6. Bluetooth is primarily used to Wi-Fi is technically a brand name
transmit data wirelessly over very for any device that adheres to the
short distances in an ad-hoc IEEE 802.11 standard.
network, with communicating Although it seems to have a
devices often being close enough similar purpose to Bluetooth, in
for a person to be holding both of that it connects devices over a
them. fairly limited range, Wi-Fi is
It is used more frequently now than meant to replace the older
infrared communication as that standard Local Area Network,
traditionally relies on line-of-sight that would use Ethernet cables
to communicate with another with PCs and laptops.
device, whereas the radio waves in Wi-Fi also uses more power than
Bluetooth technology negate this Bluetooth, allowing it to have a
need to a certain extent. larger range from the router.
One advantage that Bluetooth also This also means that data can be
has is that, despite its relatively transferred much faster due to a
narrow frequency range (2402 to higher bit rate.
2480 MHz), communicating devices
rarely interfere with each other as However, Wi-Fi has been
the frequency hops across 79 criticised in the past for having
different bands in that range, security protocols that were
around 1,600 times a second. easily decrypted, leaving data
vulnerable to anyone.
7. Mobile phone networks work on a
cell based system. Wherever
coverage is supplied, the area is
separated into cells, each with
their own base station.
The cell network is needed
because of the limited amount of
radio frequencies available. By
creating nearby cells of differing
frequencies, the same ones can
be used much further away where
there is no worry of interference.
When a phone call is made, the
phone transmits signals via radio
waves to the nearest base station,
which then sends that signal to
the base station nearest to the
phone that is being contacted.
8. Mobile phones have possibly changed the world
with their ability to allow anyone to contact anyone
at anytime.
The number of people who have access to them has
risen dramatically since their commercial
introduction in the early 1980s. It is said that in
many countries, there are often more mobile
phones than people.
In some ways this has many positive effects on the
world, in terms of safety. For instance, one could
contact emergency services whenever they needed
to, even if they were far away from a town or city.
On the other hand there have been several worries
about extended use of mobile phones, such as the
risk of cancer from the absorption of radio waves to
the brain. Issues have also arisen with the constant
use of mobile phones when driving or in other
tasks that require concentration, as it may cause
fatal accidents. Many of the health-related
enquiries have been so far inconclusive though.
9. Initially an acronym for ‘RAdio
Detection And Ranging’ in WW2,
radar is now commonplace in
our lives, and is used for a wide
variety of tasks.
Radar functions through the
emitting of radio waves, which
reflect off an object and are
then detected by some sort of
receiver. Using this signal, the
distance of an object can then
be calculated from various
different factors, such as the
time taken for the signal to
return.
10. As previously stated, the uses of radar are
widespread, each with their own value.
The initial usage of radar involved detecting aircraft
in World War 2, a practice that radar is still used for
today, to great effect. Similarly, at sea, radar is used
to detect ships and other objects that would be hard
to find otherwise.
In terms of outer space, radar is used to detect extra-
terrestrial objects such as asteroids and other
planets.
It is also frequently used to predict the weather by
detecting precipitation in its many forms.
As such, radar is a very important technology that has
aided both the general public and the progress of
scientific discovery.
11. The impact that radio wave technology has
had on the world in the last century can not
be ignored
So many things that we take for granted, such
as being able to just text someone, or use the
internet anywhere in a room, rely on the
technology that research into in radio waves
has supplied us with as a planet, making it a
much smaller place with the instantaneity of
communication.
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