High frequency electromagnetic field coupling to small antennas in rectangular resonator

The integral-differential equation for the current of an electrically small antenna inside a resonator, which is induced by given sources, is solved by the so-called “Method of Small Antenna”. The calculated input impedance of the antenna in the resonator and the calculated coefficients of the mutual coupling between two antennas are compared to experimental measurements, performed within the mode-stirred chamber at the University of Magdeburg. For low resonances, when the assumption of electrically small antennas is justified, a good agreement is found.