How does the size of an antenna affect its ability to transmit and receive?
What will be an ideal response?
An antenna transmits and receives a signal most efficiently at a specific frequency when it is as long as the full length of the wave; this is called a full-wave antenna. For practical reasons, antennas are more commonly designed to be as long as an exact fraction of the wavelength, and these are called half-wave antennas, quarter-wave antennas, and eighth-wave antennas. Though not as efficient as full-wave antennas, these smaller antennas work reasonably well. When antennas with a higher gain are required, you can increase the size of the antenna to the next bigger fraction. A larger antenna exhibits a higher gain than a shorter antenna. Almost any metallic object or any object that conducts electricity will act as an antenna, but if you use an antenna that is much shorter than the wavelength for a frequency, it will not radiate any significant amount of RF. Alternatively, if the antenna is much longer than the wavelength, it will send out some RF energy, just not very efficiently, and this may affect the reliability of the transmitter circuits.
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