SIW based compact and dual-band equilateral triangular antennas

Abstract

In this paper, a substrate integrated waveguide (SIW)-based equilateral compact and dual band triangular antennas have been proposed. A SIW-based coaxial fed equilateral triangular antenna has been initially considered. The antenna is found to resonate at 5.28 GHz corresponding to U-NII-2 WLAN band. Two sides of the said antenna are made perfect electrical conductor wall with array of metallic vias and the third side is kept open which acts like a perfect magnetic conductor (PMC) wall. A single slit has been introduced on the PMC wall of the initial antenna which causes a decrease in resonating frequency from 5.28 to 4.29 GHz. The antenna has been further miniaturized by introducing another parallel extra slit on the PMC wall which leads to a decrease in the resonating frequency to 3.3 GHz. The former antenna with single slit is found to exhibit 33% miniaturization while the latter with double slits reflects 56% miniaturization. By changing the coaxial feed location of the initial antenna at off-axis position, a dual band antenna has been realized. The dual band antenna is found to excite both TE₁₀₁ and TE₂₀₂ modes efficiently with corresponding resonating frequencies at 4.18 and 8.85 GHz. The prototypes have been fabricated on Arlon AD270 substrate and simulated results are compared with the measured ones. A good agreement has been observed between the simulated and measured results.

Keywords:

• Antenna gain
• compact antennas
• dual-band antennas
• substrate
• integrated waveguide
• half-mode substrate integrated waveguide
• IEEE 802.11a WLAN U-NII-2 band
• WiMAX