RADIO COMMUNICATION AND THE MOBILE PHONE

A Wonderful Presentation by Gareth Dakin

RADIO COMMUNICATION

•A little over a hundred years since Marconi’s first

transmission , 60% of the UK enjoy the benefits of

mobile phone use.

RADIO WAVES

•Mobile phones transmit and receive signals using

electromagnetic waves or radio waves

•Electromagnetic radiation consists of oscillating

electric, magnetic fields and the frequency

FREQUENCY

•Frequency is the number of times per second at

which the wave oscillates

•This is measured in Hertz (Hz)

•Between 30 kHz and 300 GHz is what’s used for

telecommunications including radio

FREQUENCY

•The UK AM radio uses frequencies between 180

kHz and

1.6 MHz

• Mobile frequency range is between 872-960 MHz,

1710-1872 MHz and 1920-2170 MHz

RADIO COMMUNICATION USING AMPLITUDE

MODULATION

•Radio frequency wave used for radio communication

is known as a carrier wave

•The carrier wave is produced by the transmitter as

a sine wave

•For the radio wave to convey information such as

speech information needs to be added to the carrier

wave, this is modulation

RADIO COMMUNICATION USING AMPLITUDE

MODULATION

•For amplitude modulation electrical signals from a

microphone is used to vary the amplitude of the

carrier wave

•At any instant the amplitude of the carrier wave is

made proportional to the size of the electrical

modulating signal

•There are many types of modulating techniques

with different characteristics for different

applications

MOBILE PHONE NETWORKS USING RADIO

COMMUNICATION

•A mobile phone sends and receives information via radio

communication

•Radio frequency signals are transmitted from the phone to

the nearest base station

•Incoming signals are sent from the base station to the

phone at a slightly different frequency

•Base stations link mobile phones to the rest of the network

MOBILE PHONE NETWORKS USING RADIO

COMMUNICATION

•Signals are transmitted to the network via

telephone cables or higher frequency radio links

between an antenna

•Each base station provides radio coverage to a

geographical area known as a cell

BIBLIOGRAPHY

Geo Tau Aisay (2009) Radio waves [Online image]. Available from:

http://www.ieeeghn.org/wiki/index.php/Radio_Waves [24/01/11]

Hardware sphere (2010) Nokia to charge phone via radio waves [Online image]. Available from:

http://www.hardwaresphere.com/2009/06/12/nokia-to-charges-phone-via-radio-waves-in-201x/

[24/01/11]

Lee global history network (2011) Radio waves modulated by amplitude and frequency [Online

image]. Available from: http://www.ieeeghn.org/wiki/index.php/Radio_Waves [25/01/11]

Public telecommunication networks unit (2001) How mobile phone networks work [WWW] Ofcom.

Available from: http://www.sitefinder.ofcom.org.uk/mobilework.htm [18/01/11]

Queensland university (2010) Mobile phones [Online image]. Available from: http://

www.fmd.qut.edu.au/campus_services/cleaning/waste_disposal/mobile_phone.jsp [24/01/11]

Virtual systems e-blacktech (unknown) Structure of cellular network [Online image]. Available

from: http://www.e-blacktech.com/telephoneservice/cellphones.html [25/01/11]