High-gain quasi-shielded tapered-slot antennas for 50–65 GHz switched-beam systems

A tapered-slot antenna (TSA) with microstrip-to-slotline transition is demonstrated for millimeter-wave wireless communications. Two antennas with different aperture widths and lengths are fabricated on a Teflon substrate (ε_r = 2.2, t = 10 mils), and result in a measured S₁₁ <;-8 dB with a gain of 11 dB and 7 dB at 55-63 GHz for an aperture of 3.5 mm and 1 mm, respectively. To validate its performance inside portable mm-wave systems, two metal shielding planes are placed above and below the antennas. The results show that the TSAs maintain good impedance matching and gain with a metal plane height of 1-3 mm, depending on the aperture. A four-element TSA array is also demonstrated for switched-beam systems.