(CT) Radio and Wireless Lesson

Radio and Wireless Lesson

Introduction-

  

 

Explore

Energy is all around us. There is electrical energy, acoustical energy, and natural energy through the earth’s magnetic fields and sunlight. Electromagnetic radiation is the flow of energy, photons, through space. Review the following NASA video on radio waves for a greater understanding of radio waves. 

 

 

How does radio communications work? Electrical information is converted to a signal for transmission and then modulated to a carrier wave enabling greater distance and frequency conversion. Radio waves are then propagated from the transmitter through an antenna for the specific wavelength. Another antenna designed for that wavelength will receive the signal that is transmitted and it will be picked up by the receiver and demodulated to the designated frequency channel. Just like the radio in a stereo or car, the receiver must be tuned to the frequency of the transmission in order to select that signal and decode for use. The frequency is selectable by electronics. The range of wavelengths is associated with the selected antenna. Regardless of the information being sent, this is the basic technique of radio and wireless communications.

Explore the presentation below to learn more about the use of radio waves for communications.

   

Challenge

 

Take Away

Do you listen to AM radio? Have you noticed the difference in sound quality from FM?

The advantage of Frequency Modulated (FM) radio over Amplitude Modulated (AM) radio is the quality of sound reproduced. AM radio is produced through amplitude modulation of the carrier wave to transport the signal. This technology allows for amplification of all information, including noise, emitting from the source. FM radio was an improvement in that the carrier wave is changing frequency which thus eliminates any additional noise or static.

Turn your radio on and compare the difference.

 

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