Design of a single-feed dual-frequency microstrip antenna

This paper presents a new dual-frequency design for microstrip patch antennas. The proposed dual-frequency antenna is excited by a single probe feed, and the feed position is on the rectangular patch that is surrounded by a square-ring patch. The rectangular patch not only acts as a coupling-strip feed to the square-ring microstrip antenna at a lower frequency, but can also be resonant at a higher frequency. In addition, the two operating frequency bands can produce the same linear polarization or dual polarizations. Details of the antenna designs are described. The experimental and simulated results are also shown and discussed. (c) 2005 Wiley Periodicals, Inc.