Theoretical investigations on equilateral triangular dielectric resonator antenna

Equilateral triangular dielectric resonator antenna (ETDRA) is investigated here analytically for TMz mode. For theoretical analysis, the triangular surfaces on the top and bottom of the isolated ETDRA are modelled either as perfect magnetic conductors (PMC) or imperfect magnetic conductors (IPMC), whereas the side walls having rectangular cross-section are modelled as PMC only. The concept of reduction in effective size due to the avoidance of any corner by the electric field lines is used for the first time to predict the resonant frequency for different TMmnpz modes with an accuracy of 4%. Consequently, an expression is also given here for efficient evaluation of effective dimensions of the ETDRA for various TMmnpz modes. Closed form expressions for the far-field radiation patterns of dominant TM101z mode are also presented using both (PMC and IPMC) models. Theoretical results are compared with published data as found in the open literature. One antenna prototype is also fabricated, tested and measured for further verification. It is found that the authors' theoretical results are in close agreement with measured data.