For arguments sake lets say I have a receiving antenna that has been positioned between two large conductive plates. Are there any differences in how that antenna operates (gain, efficiency etc.) when the conductive plates are electrostatically charged (such that a constant electric field forms between the two) compared to if the plates were left neutral?
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$\begingroup$ The largest effects will be from polarization of the air or other medium surrounding the antenna, which would alter the permittivity and lead to changes in gain. For these effects to be prominent the field would have to be strong. Alas, I am not an expert in antennas, however, so I can't be quantitative. Sorry, I mistook your question at first for one of a more practical nature, my thought being: just get rid of all that metal. $\endgroup$– Albertus MagnusCommented Mar 26 at 18:34
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$\begingroup$ The operation of a receive antenna is not affected by a static external electric field. Now it is true that an incident radiation or the reflection from the antenna may move the charges on the capacitor and that accelerated motion may induce a secondary radiation, scattering, from the plates some of which could be received by the antenna. $\endgroup$– hyportnexCommented Mar 27 at 0:30
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There should be no influence on the RF performance of the antenna unless the electric field is so strong that electrostatic forces would move or deform the antenna, or that air ionization with plasma formation and conduction (e.g., lightning) sets in, which could lead to absorption and/or to changes in the oscillation pattern of the electromagnetic field associated with the antenna and thus to its receiving properties.
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$\begingroup$ Does it change at all for a non-repeating waveform e.g. a transient? Does the static field act similar to a damping force on the movement of electrons, causing the measured transient to settle faster than it otherwise would? $\endgroup$ Commented Mar 27 at 9:50