Definitions• Radio Waves - Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light.• Electromagnetic Radiation - Electromagnetic radiation (EM radiation or EMR) is a form of energy emitted and absorbed by charged particles, which exhibits wave-like behaviour as it travels through space.• Wikipedia Definitions
WiFi • Wireless networks use radio waves to transmit signals.1. A computer’s wireless adapter translates data into a radiosignal and transmits it using an antenna.2. A wireless router receives the signal and decodes it. The routerthen sends the information to the internet using a physical, wiredEthernet connection. • They transmit at frequencies of 2.4 GHz or 5 GHz. A higher frequency allows it to carry more data.
WiFiWhy are the radio waves important and why are they used?• Radio waves carry data back and forth from the wireless adapter and the router. This allows users to use the internet wirelessly.
Mobile computing• Mobile networks also use radio waves to transmit signals back and forth, from the mobile phone to the base station.• A base station is usually never more than 2 or 3 miles away.• The signals that are transmitted are also used to carry data back and forth.• The use of radio waves in mobile computing is important for accessing the internet, (which is made up of data), from anywhere wirelessly.
Television broadcasting• Television (TV) is a telecommunication medium for transmitting and receiving moving images, with or without sound.• The antenna receives the signal in the form of electromagnetic waves that is broadcasted from the television station.• The signal is received and displayed on television screens.• A dish works in the same way. It receives waves broadcasted from the television station, and the signal is sent through a cable into the house.
Television broadcasting –digital switchover• The on-going switchover the in the UK affects any TV that receives its signal through an antenna.• Digital TV offers more benefits than analogue, including a stronger TV signal. This image shows how signals are transmitted for television broadcasting into the home.
Bibliography• Alcohen2006. Is 3G radio waves or sattellite? . Available: http://wiki.answers.com/Q/Is_3G_radio_waves_or_sattellite. Last accessed 20/01/2012.• Marshall Brain. How WiFi Works. Available: http://computer.howstuffworks.com/wireless-network1.htm. Last accessed 20/01/2012.• Ruth Netting. (2007). Radio Waves. Available: http://science.hq.nasa.gov/kids/imagers/ems/radio.html. Last accessed 20/01/2012.• Digital UK. (2011). Switchover. Available: http://www.digitaluk.co.uk/home. Last accessed 20/01/2012.