Wideband Dielectric Patch Antenna With Stable Radiation Pattern

Abstract

A dielectric patch antenna (DPA) with a wide impedance bandwidth and a stable radiation pattern is investigated. By making use of the fact that the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E</i> -field distributions of different modes of the DPA are distinctive, multiple air regions are elaborately introduced into the DPA. They can manipulate the resonant frequencies of different modes. As a result, the impedance bandwidth can be enhanced by merging the fundamental TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">101</sub> and higher order modes TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">121</sub> , TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">321</sub> , and TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">141</sub> . The air regions can also regulate the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E</i> -field distributions of the higher order modes TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">321</sub> and TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">141</sub> , reducing the out-of-phase <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E</i> -fields and improving the radiation pattern. To validate the idea, a prototype operating in the X-band was designed, fabricated, and measured. Reasonable agreement between the measured and simulated results is observed. The measured 10 dB impedance bandwidth (| <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> | <−10 dB) is 44.9% (8.3–13.1 GHz), with the measured peak boresight realized gain being 8.95 dBi. Stable radiation patterns can be obtained within the working band.