2. Introduction
When we think of radio waves, we assume they
are only used for radio and broadcasting. In
reality, they are used for many more things ,
these include mobile phones, WIFI and
television . Through this presentation I will
discuss the use and importance of radio waves
and how they apply to mediums beyond radio
broadcasting.
3. Radio Waves
With regards to the electromagnetic spectrum, radio waves have the
longest wavelength. The following diagram represents the
wavelength for AM, FM and TV.
As you can see from the diagram, AM has the longest wavelength as it is
broadcasted further than TV and AM radio. With AM radio having a wider
coverage, this implements issues of quality. The bandwidth is usually around
5 kHz, although the human ear has a musical range of 20hz which leads to
an imperfect sound when compared to the superior FM radio quality. Having
discussed this, it leads me to further research into how radio waves take part
in mediums other than radio.
4. WIFI
WIFI uses radio waves in a similar way to how a radio
operates. This process involves the computer
translating data into a radio signal which is then sent
out through an antenna. This signal is then received by
a wireless router, which goes through the process of
decoding. The router then sends the information via a
wired Ethernet cable.
A notable difference between WIFI and other radio
waves is the amount of data that is transmitted. The
frequency transmitted via WIFI is either 2.4 GHz or 5
GHz. With this frequency being relatively high, It allows
more data to be transferred. Cell phones and
television, in comparison use a lower frequency due to
less data being needed for the signal.
5. Mobile phones
From an international perspective mobile phones are referred to as ‘cell
phones’. The term ‘cell’ derives from how a mobile phone operates.
the function involves a cellular pattern, which is basically a number
of areas that are divided into cells. These cells require a base
station which make up the network and have both a radio and
transmitter tower. In large cities, they can have hundreds of towers
set up to keep up with the high demand of mobile phone use.
A mobile phone carries little power in terms of transmission, and
therefore connects to the nearest transmitter within a base station.
It can be noted that in more urban areas it is likely to get a stronger
signal , in comparison to rural areas where less base stations are
likely to be.
6. Television
The antennae of a television is used to receive the signal, which is
found in the form of electronic magnetic waves (like a radio)
The television signal is sent in two forms; one is the video which is
through AM , and sound can be recieved by either AM or FM signal.
On average a TV signal needs a bandwidth of 4 Hz , although a
further 2 Hz needs to be acounted for sound.
The video signal (separately) then goes through the process of
amplitude- modulation along with the sound which is then merged
and picked up via the antennae
7. Radar
A radar works through a signal being transmitted, which bounces of an
object which is then received by a receiver. Radars use
electromagnetic waves and microwaves
A radar is divided into a transmitter ,switch, antenna, receiver, data
recorder, processor and output device. The received signal is sent to a
recording device , and is later interpreted and presented.
8. What are the importance of radio
waves ?
The significance of radio waves during the 21st century goes far
beyond communication. Notably, with new technological
advancements such as SATNAV, it is true that we have surpassed
the initial intentions of use for radio waves.
It is true that radio technology was responsible for overseas
connection and led to the speed of receiving transmissions from
such a long distance, considerably shorter.
Radio waves are relied upon in such fields as the military and
aircraft based jobs and serve importance , particularly with regards
to AM radio transmissions.
9. Conclusion
The importance of radio waves in modern day is highly depended
upon, whether it be for radio or other extensive medias we use
radio waves for. Without it, we would suffer in terms of long
distance communication and also the luxuries of such things as
satellite navigation which is one of many devices that make modern
day living so convenient.
10. References
How WIFI works (WWW) Marshall brain and Tracy V. Wilson (2011)
ttp://computer.howstuffworks.com/wireless-network1.htmhttp://
www.infoplease.com/ce6/sci/A0860617.html
Uses of radio waves (WWW) Columbia university (2007)
How cell phones use radiation (WWW) Marshall Brain, Jeff Tyson and Juila Layton
(2011) http://electronics.howstuffworks.com/cell-phone2.htm
http://science.hq.nasa.gov/kids/imagers/ems/radio.html Radio waves (WWW) Ruth Netting
(2007)
Image source- http://science.hq.nasa.gov/kids/imagers/ems/radio.gif
http://en.wikipedia.org/wiki/Radio#Video Television radio signal (WWW) (2011)
http://www.ig.utexas.edu/research/projects/mars/education/pictures/radar/rad_system.g
if Radar diagram (WWW)
http://www.ig.utexas.edu/research/projects/mars/education/radar_works.htm
How radars works (WWW) Institutes for Geophysics
