2. History There is debate about who first invented the radio Marconi and Tesla both invented it at around the same time, but Marconi was eventually awarded the radio patent The first radio voice broadcast was by reginald Fessenden in 1906
3. What are radio waves? A form of electromagnetic radiation Vary in wavelength (from 1mm – 100,000km) Travel at the speed of light Used for:- - Mobile radio communication - Broadcasting - Radar - Computer Networks - And more... Believed by some that they can cause Cancer and Leukaemia
4. 4 Types... They are divided into 4 Long Wave – 1-2km Medium Wave – 100m VHF – (very high frequency) 2m UHF – (ultra high frequency) <1m
5. Amplitude Modulation – How It Works 1. Data impressed onto an AC Carrier Waveform 2. Modulation 3. Data carried through radio waves 4. Received by an antenna 5. Demodulation
7. How Mobile Phones Work Mobile phones use "cells” Each cell has a base station at its centre. The base station sends and receives calls The mobile phone communicates with the base station using radio waves. As you move through cells, the calls are transmitted from the nearest base station
9. References wiseGEEK (n.d.) What are radio waves? [WWW] Available from: http://www.wisegeek.com/what-are-radio-waves.htm [Accessed 26/1/11] Wikipedia (24.1.11) Radio Waves [WWW] Available from: http://en.wikipedia.org/wiki/Radio_waves [Accessed 26/1/11] Darvill Clara (n.d.) Radio Waves [WWW] Available from: http://www.darvill.clara.net/emag/emagradio.htm [Accessed26/1/11] Ofcom (n.d.) How Mobile Phone Networks Work [WWW] Available from: http://stakeholders.ofcom.org.uk/sitefinder/glossary/how/ [Accessed 26/1/11) AskComReg (n.d.) Coverage [WWW] Available from: http://www.askcomreg.ie/mobile/coverage.44.LE.asp [Accessed 26/1/11]