Do antennas resonate?
A radio antenna is a form of tuned circuit consisting of inductance and capacitance, and as a result it has a resonant frequency. This is the frequency where the capacitive and inductive reactances cancel each other out. Antennas for short wave applications are larger still.
What is Hertz antenna?
The length of the total wire, which is being used as a dipole, equals half of the wavelength (i.e., l = λ/2). Such an antenna is called as half-wave dipole antenna. This is the most widely used antenna because of its advantages. It is also known as Hertz antenna.
Does a resonant antenna work better than a non-resonants antenna?
Reply #1 from “Retired EE with aerospace and biomedical experience & 8 patents.” Yes a resonant antenna properly matched to the transmitter or reciever will work better a non-resonant antenna. Any antenna discussion MUST include the frequency or frequency band in order to be more detailed.
What does a too long non resonant dipole look like?
Let’s look at a resonant dipole, Figure 1 (a), a too-long non-resonant dipole, Figure 1 (b) and a too-short non-resonant dipole, Figure 1 (c). The resonant antenna looks just like a resistor.
What kind of antenna has no SWR and no resonance?
Its antenna efficiency is zero, because it does not radiate any of the power. So here we have a great example of a low SWR but no resonance and no radiated power. The half-wave dipole is a common ham radio HF antenna. Now let’s look at the classic center-fed half-wave dipole in free space.
What happens at frequencies other than the resonant frequency?
At all frequencies other than its resonant frequency the antenna presents a reactive impedance component (inductive or capacitive) that adds to the resistive component. If the source impedance is still resistive, it is no longer matched to that of the antenna, so the power delivered to it is reduced.