A Compact Wide-Beam Open-Loop Antenna for Small Flight Vehicle Applications

In this letter, a compact wide-beam open-loop antenna is presented for small flight vehicle communication applications. The object is comprised of a disc-shaped metal pedestal and a vertical substrate. The primary radiated structure is the open loop, which is printed on the vertical substrate and fed by an edge coaxial line. Wide beam characteristics have been verified at 3.542 GHz to 3.612 GHz, with a half-power beamwidth (HPBW) of 278° and 240° in the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">xoz</i>- and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">yoz</i>-planes, respectively. The total dimensions are calculated as π × 0.2λ<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> × 0.2λ<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> × 0.09λ<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub>, where λ<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> represents the wavelength of the central frequency in free space. The suggested design prototype has been fabricated and evaluated inside the microwave anechoic chamber, and the measured results closely correspond to the simulated. With its wide beam, compact size, lightweight, and affordable price, the suggested design is anticipated to be a good candidate for small flight vehicle applications.