Micromachined 95 GHz waveguide-fed plastic horn antennas

Waveguide-fed plastic horn antennas have been demonstrated for W-band applications using a versatile and cost-effective micro hot embossing process. The three-dimensional (3D) polymer structure with internally coated conductor is composed of a pyramidal horn, an E-plane waveguide bend, two resonant cavities for impedance matching and a connecting rectangular waveguide. Measurement results show broadband characteristics in W-band with a return loss of better than-10 dB; the bandwidth is 25.2 GHz between 76.5 and 101.7 GHz (26.5%), and the 3 dB beam widths of the E- and H-plane gain patterns at 95 GHz are 26° and 23°, respectively. The antenna gain is 17.04 dB at 95 GHz and the cross-polarization discriminations for E- and H-plane are 19.5 dB and 22.2 dB, respectively.