Wideband Dielectric Patch Antenna With Stable Radiation Pattern

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
E
-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
₁₀₁
and higher order modes TM
₁₂₁
, TM
₃₂₁
, and TM
₁₄₁
. The air regions can also regulate the
E
-field distributions of the higher order modes TM
₃₂₁
and TM
₁₄₁
, reducing the out-of-phase
E
-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 (|
S
₁₁
| <−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.