Directional and polarization radiation characteristics of a horizontal impedance vibrator located above a rectangular screen

Resumo

An algorithm of calculation of the directivity, energy, and polarization radiation characteristics of an arbitrarily oriented thin impedance vibrator located above a rectangular screen is developed on the basis of the asymptotic solution to the 3D problem of diffraction of the field of the electric vibrator by a perfectly conducting rectangular screen. The asymptotic expressions for the current of an impedance vibrator having the electric length 0.4 ≤2l/λ ≤ 0.6 are applied. The asymptotic solution is obtained on the basis of the method of the uniform geometric diffraction theory. The aforementioned characteristics are studied in the whole observation space in the far zone. The effects of the thickness and length of the vibrators and the effects of the distances from the screen on the resonance values of the distributed surface impedance and the corresponding radiation characteristics are shown. The resonance vibrator’s radiation characteristics that depend on the screen dimensions are analyzed. The amplitude and polarization patterns of a horizontal vibrator located above a square screen having optimal dimensions are calculated.