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→Half wave dipole
* Dipole antennas are one of the earliest used antennas. The antenna used by Hertz in his experiment to transmit electromagnetic waves was also similar to dipole antenna. Its geometry is linear and its structure is, to simply speak, two wires in a line.
* As the name suggests, the length of this antenna is half of its wavelength at the desired frequency of operation. The signal is feeded to this antenna midway. It has an omnidirectional radiation pattern and linear polarization.
* It has low directivity (2.15 dB) and input impedance of 73 + j42.5 ohm. <ref>http://www.antenna-theory.com/antennas/halfwave.php</ref> The antenna can be made resonant (input impedance purely real) by reducing length of antenna to 0.48 fraction of wavelength
=== Folded dipole ===