Resonance frequency of an equilateral triangular microstrip antenna

We propose two simple and accurate closed-form models to compute the resonance frequency of an equilateral-triangular microstrip patch antenna on standard single layer and suspended substrates. The models have accuracy better than 0.7% for all cases for substrates having ε_r = 1.09 to 10.5. We also compare the accuracy of the commercial full-wave analysis software, Microwave Studio, against the available experimental results. It exhibits average accuracy of about 2.94% for the suspended structure and 0.97% for the standard substrate. The proposed models can be easily extended to the multilayer composite substrate. The models are suitable for interactive CAD of design and optimization of equilateral-triangular microstrip antenna.