A COAXIAL FED FLOWER SHAPED MULTI-ELEMENT SUSPENDED PATCH ANTENNA WITH ILLUMINATION AREA IN THE FORM OF A RING

摘要

A multi-element suspended microstrip patch antenna with flower shaped printed pattern excited at its centre by a coaxial feed is presented. All the radiating patch elements are electromagnetically coupled symmetrically to the same coaxial feed, thereby eliminating the need for a separate power division network. With three or more elements, the antenna beam illuminates an area in the form of a ring symmetric about the axis perpendicular to the plane of the patch elements. The antenna offers a gain in the range 5-6 dBi with a 3 dB beam-width of about 50° in any cross-sectional plane passing through the vertical axis. Details of the simulation studies carried out on the antenna with one to five elements and experimental results on the fabricated antennas are presented. The antenna has potential applications in remote sensing and biomedical areas, particularly for microwave imaging.