Aperture-coupled equilateral triangular microstrip array antennas for single and multiband operation

A novel design of aperture-coupled two-element equilateral triangular microstrip array antenna (ATEMSA) is proposed for multiband operation. A horizontal slot of optimum dimension if loaded at the center of radiating elements of ATEMSA, it converts multiband into single wideband without changing the nature of broadside radiation characteristics. The magnitude of impedance bandwidth is found to be 3.1 times more when compared to the impedance bandwidth of conventional equilateral triangular microstrip antenna (CETMSA). The gain, azimuthal radiation patterns and input impedance of proposed antennas are studied and reported. Details of the antenna design are given and experimental results are discussed.