Simulation and experimental investigation of the radiation efficiency of a dielectric resonator antenna

In this paper, we attempt to get a deeper insight into the radiation efficiency of the DRA and the difference of accuracy between the D/G method and the Wheeler cap method by measuring a simple rectangular DRA at C band with both methods. It is, on one hand, confirmed that, the radiation efficiency of the DRA can be as high as 98% at C band. On the other hand, the comparison of the two efficiency measurement methods shows discrepancies that can be explained from simulations. The radiation efficiency obtained by the D/G method is generally lower than that by the Wheeler cap method. The paper demonstrates that this arises from the effect of cross-polarization and from the finite sampling of the radiation pattern used in the D/G technique, which are inherent defects of this method.