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(Tying it all together!). Using Electromagnetic Radiation to Communicate. In the beginning. Most of our everyday communication starts off as sound waves. These are NOT electromagnetic radiation – sound waves are mechanical and need a medium to move through.
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(Tying it all together!) Using Electromagnetic Radiation to Communicate
In the beginning... • Most of our everyday communication starts off as sound waves. • These are NOT electromagnetic radiation – sound waves are mechanical and need a medium to move through. • To make long distance communication possible, we need to convert the sound waves to electromagnetic radiation.
Label the picture with the part of the spectrum used for each communication device
Bandwidth • In electronic communication, bandwidth is the width of the range (or band) of frequencies that an electronic signal uses on a given transmission medium. • Bandwidth is expressed in terms of the difference between the highest-frequency signal component and the lowest-frequency signal component. It is measured in Hertz. • A typical voice signal has a bandwidth of approximately 3 kHz and an analog television broadcast video signal has a bandwidth of 6 MHz
The Fight for Bandwidth • Go to the following websites: • http://online.wsj.com/article/SB10001424052748703574604574499730302393274.html • http://communication.howstuffworks.com/telephone6.htm • Use the information (and any other information that you find) to answer outcome 25 Discuss problems produced by the limited range of the electromagnetic spectrum available for communication purposes.
The waves involved • http://www.brainpop.com/technology/communications/cellphone/ • http://www.brainpop.com/technology/communications/radar/
How a Radio Works AM FM • http://www.brainpop.com/technology/communications/radio/
Applications of Reflection • Plane mirror: • Concave mirror: • Convex mirror: • Ionosphere:
A “long answer” question • Describe ways in which applications of reflection of light, radio waves and microwaves have assisted in information transfer.