Radio Waves and Telecommunications Naomi Bowden Tech1002 Z Allman Wednesday 9am
Radio Waves Radio waves are transmitted and received using electromagnetic waves also known as radio waves. Electric and magnetic fields are oscillated to determine the frequency. Frequency (oscillates per second) determine what they can be used for.
The standard frequency bandwidth for telecommunications, including broadcast television and radio is set at between 30KHz and 300 GHz (ofcom.org.uk 25/01/11)
Radio Communication using Amplitude Modulation A carrier signal is used to modulate sound waves such as speech and music, rather than the frequency being modulated as in FM radio broadcasts.
Electrical signals given off by microphones and other devices are used to vary the amplitude of the carrier wave rather than the frequency.
How Mobile Phone Networks Use Radio Communication 60% of the UK population, around 40 million people, own and use a mobile telephone
Mobile phones send and receive signals to and from the nearest base station. These radio waves are then sent back to the devices at a slightly different frequency which vibrate within the phones speaker so that our ears can convert the signals to voices or music.
Base stations link phones together (both mobile and landline) and transmit the information given either through phone cables or high frequency radio links via antenna.