definition of Q for an antenna [needed]

Hello;
Please explain me wjat is quality factor of an antenna? Has antenna a resonance equivalence circuit?

Hi,

I am not quite sure, but I think that the quality factor of the antenna is the center frequency divided by the bandwidth.

Some types of the antennas are resonant antennas such as the dipole and patch antenna. They have resonance at certain frequencies at which they radiate efficiently. But I never saw an equivalent resonace circuit of an antenna. Most people use simply the input impedance and the refletion coefficient (s11)

Best Regards,
Adel_48

Can you explain concept of Q for an antenna?

Q is officially the energy stored divided by the energy loss per radian of cyclic operation. The bandwidth of a tuned circuit is related to this, but applying a Q value to distributed circuits does not match the original definition.


As far as equivalent circuits, you can always get one by matching a certain number of impedance points in frequency between the antenna and the RLC network. You will only get a good match over a narrow frequency range.

the total power constant ,when the value of Q is grow,the energy stored in the vantenna is becoming more.