Reactively loaded loop antennas with reflectors for circular polarization

There have been several attempts to expand the capabilities of loop antennas by impedance loading. In this paper, a new structure is proposed in which a reactance loads a one‐wavelength loop antenna with a reflector. It is shown that this structure is in principle suited as a circularly polarized antenna. The loading reactance is placed at 45o from the feed point. It is shown from numerical calculations that there exists a dimension for which a good axial ratio is obtained if the reactance is changed. Numerical results are shown for this axial ratio, input impedance, current distribution and radiative pattern at this dimension. From these results, general characteristics of this structure are found. From the model experiment, it is confirmed that circular polarization is generated from this structure.