Three-Port Pattern- and Polarization-Diversity Rectangular Dielectric Resonator Antenna

Abstract

In this communication, a compact three-port pattern- and polarization-diversity rectangular dielectric resonator antenna (DRA) is investigated. The antenna is designed based on three TE modes, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{TE}^{x}_{\delta 11}$ </tex-math></inline-formula> mode, asymmetric <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{TE}^{y}_{1\delta 1}$ </tex-math></inline-formula> mode, and the presented quasi-omnidirectional mode, symmetrical <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{TE}^{y}_{1\delta 1}$ </tex-math></inline-formula> mode. The radiation mechanism of the presented symmetrical <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{TE}^{y}_{1\delta 1}$ </tex-math></inline-formula> mode is revealed by the theory of array and the geometric theory of diffraction. The asymmetric and symmetrical <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{TE}^{y}_{1\delta 1}$ </tex-math></inline-formula> modes are supported by different boundary conditions. Based on the field-distribution difference between the two modes, an artificial boundary made of metal strips is electroplated on a portion of the side of the DRA to excite the symmetric and asymmetric <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{TE}^{y}_{1\delta 1}$ </tex-math></inline-formula> modes simultaneously. For verification, a three-mode diversity DRA <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{^{^{}}}$ </tex-math></inline-formula> is designed at 5.8 GHz. The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{TE}^{x}_{\delta 11}$ </tex-math></inline-formula> , asymmetric, and symmetric <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{TE}^{y}_{1\delta 1}$ </tex-math></inline-formula> modes are excited by differential probes, slot in the center, and slots at the periphery, respectively. The overlapping 10-dB bandwidth of the three ports covers from 5.7 to 5.9 GHz. The envelope correlation coefficients and mean effective gain ratios are lower than 0.13 and 1.5 dB, respectively.