A Microstrip-coupled Slot-loop Antenna for Integrated Receivers in the Millimeter-wave Band

A square-loop slot antenna, printed at the back surface of an extended hemispherical lens, is examined as a candidate for ( ) millimeter-wä e mm-wa ̈e integrated-circuit Schottky-diode mixers. The loop slot is etched in a microwä e substrate, and coupled to a microstrip line section printed on the other side of the substrate. A Schottky barrier diode shunted to ground is the mixing de ̈ice. The input impedance of the antenna has been optimized to conjugate match the Schottky diode. To design and optimize the antenna, an efficient full-wa ̈e method of ( ) moments MoM technique, which sol̈ es the mixed potential integral ( ) equation MPIE in the stratified medium, has been de ̈eloped. Patterns ha ̈e been computed using the physical optics approximation and diffraction theory. The proposed configuration shows ̈ery wideband performance. Simulation results compare well with measurements. The proposed configuration is suitable to be scaled down for operation in the ( ) submillimeter-wä e submm-wä e band. Q 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 18: 91]95, 1998. ( )