Approximate Theoretical Investigations on Isosceles Triangular Dielectric Resonator Antennas and Experimental Validation

Theoretical and experimental investigations on isosceles θ
_i
- θ
_i
- φ
_i
triangular dielectric resonator antennas (TDRAs) are presented here for TM mode for the first time. Trilinear transformation is slightly modified to obtain the approximate solutions for eigenfunction and eigenvalue. Limitations of the theory are discussed. Closed form expression is given here to predict the resonant frequency with a maximum error of 4%. It is found that isosceles TDRA produces a peak in the broadside direction at fundamental TM
₁₀₁
^z
and higher order TM
₁₀₃
^z
modes. Three isosceles TDRAs having θ
_i
= 60°, 70°, and 75° are fabricated for experimental validation.