A Wideband Triple-mode Substrate Integrated Waveguide Cavity-backed Slot Antenna

摘要

In this paper, A wideband substrate integrated waveguide (SIW) cavity-backed slot antenna with triple resonances is presented. The SIW cavity used for the antenna is fed by an offset coaxial probe to excite the TE₂₁₀ and TE₄₁₀ modes, and two radiation slots are etched on the left and right sides of the cavity. The TE₄₁₀ mode is split into two resonances by the perturbation of the two slots. Besides, several pairs of shorting vias are loaded inside the cavity for moving up the TE₂₁₀ mode so as to merge it with the two split TE₄₁₀ modes. At the center of the cavity, a shorter slot and two shorting vias are introduced for the impedance matching. Thus, these three modes can be allocated together to achieve a wideband characteristic. Simulated results show that the proposed antenna has a bandwidth of 20.2% (from 4.7 GHz to 5.75 GHz) and a peak gain of 9.88 dBi, while keeping a low profile of 0.038 λ₀ (wavelength in free space).