An Analytical Approach for Testing the Air gap Tuning Effect on an Equitriangular Microstrip Antennaâ€™s Radiation
L. Djouablia 1,*, A. Labbani2, A. Benghalia3
Signals and Telecommunication Journal, Vol. 4, No. 1, 2015.
DOI: 
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Abstract:
Using a combined approach, the effect of air gap tuning on the resonant frequency and radiation field of an equitriangular microstrip antenna is presented in this paper. An equilateral triangular patch is implemented on an isotropic
dielectric with an air gap inserted under this one in order to estimate the influence of an air gap on radiation antennaâ€™s characteristics. The problem is analysed in spectral domain using the moment method and an electric field integral equation combined with a mathematical approach. However, the dyadic Greenâ€™s functions corresponding to the proposed structure are
developed and the Fourier transform of basis current components are calculated mathematically using â€œthe reference elementâ€ method. A numerical result shows that the change in resonant frequency, bandwidth and radiation field of the
antenna is due primarily to a small disturbance of the air gap thickness and consequently substrateâ€™s equivalent permittivity.