What is Hertzian dipole?
A Hertzian dipole is commonly defined as an electrically-short and infinitesimally-thin straight filament of current, in which the density of the current is uniform over its length.
What is Hertzian antenna?
The Hertzian dipole is a linear. antenna which is much shorter than the free-space wavelength: In 1887, Hertz used a sub-wavelength antenna to generate (transmit) and detect (receive) radio waves – the first wireless broadcast.
Which antenna is also called a Hertzian dipole?
Hertzian dipole. A dipole antenna, developed by Heinrich Rudolph Hertz around 1886,[citation needed] is an antenna that can be made by a simple wire, with a center-fed driven element for transmitting or receiving radio frequency energy.
Why is Hertzian dipole so named?
This type of antenna is called a Hertzian dipole, after the German physicist Heinrich Hertz. , as is to be expected if energy is conserved. associated with the real resistance is due to ohmic heating of the antenna.
What is the directivity of a Hertzian dipole antenna?
The peak of G(θ, φ) is known as the directivity of an antenna. It is 1.5 in the case of a Hertzian dipole. If an antenna is radiating isotropically, its directivity is 1.
What is the theoretical gain of a Hertzian dipole?
The dipole antenna has a power gain of 1.64 or 10 log 1.64 = 2.15 dB above isotropic. Hence option B is correct.
What is the radiation resistance of a Hertzian dipole?
If the frequency is changed to 3 MHz (20 = 100 m), the radiation resistance is 7.9 un and the current required to radiate 1 W is 356 A! Nevertheless the Hertzian dipole serves a useful purpose in that the far fields of a Hertzian dipole are virtually identical to the far fields of most other practical antennas.
How do you calculate the radiation resistance of a Hertzian dipole?
The radiation resistance of a Hertzian dipole antenna is given by:
- R r a d = ( 2 π η 3 ) ( l λ ) 2 —(1)
- R r a d = 80 π 2 ( l λ ) 2.
- R r = 80 × π 2 ( 1 10 ) 2.