Experiment on an aperture-coupled leaky-wave antenna with a pencil beam

A frequency‐scanning leaky‐wave antenna with an aperture‐coupled feeding structure is presented. The aperture‐fed structure is used to excite the microstrip first higher mode. In order to suppress the dominant mode, we add a sequence of covered wire in the center of this antenna. The measured H‐plane main beam is a pencil beam, and is continuously scanned 12° as the frequency varies from 9.85 to 10.27 GHz. This feeding structure is very suitable for active phase antenna array applications. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 5–8, 1999.