High-Efficiency 3-D Antenna for 60-GHz Band

Design and measurement of a novel millimeter-wave antenna are presented. The radiating structure is based on a 3-D metallized molded plastic part which is soldered onto a thin, single-layer circuit board, and fed by a microstrip line of 50-$\Omega $ impedance. The 3-D structure is free of indentations and simple to manufacture. The -10 dB impedance bandwidth exceeds the 57-64 GHz license-exempt frequency band. Measurements show a gain of 5.8 dBi, half-power beamwidth of 85°- 90°, and indicate a high radiation efficiency of 90%.