DESIGN OF ANTENNA-EMBEDDED COMPOSITE SANDWICH STRUCTURE USING OPEN CONDITION FOR WIDE BANDWIDTH AND HIGH GAIN

摘要

The present study aims to design electrically and structurally effective antenna structures. The basic design concept is a composite sandwich structure in which microstrip antenna is embedded and this is termed composite smart structure (CSS). The most important outstanding problem is that composite materials of structural function cannot be used without reducing antenna efficiency. This is a significant design problem that needs to be solved in practical applications. Therefore, the effect of facesheet on antenna performances is studied in the first stage. Changes in the gain of microstrip antenna due to facesheet have been determined. 'Open condition' is defined when gain is maximized. The open condition can be made with the thickness of outer facesheet by controlling its position. In the design of CSS, glass/epoxy composites and Nomex honeycomb are used with exploiting open condition. Experiments, confirm that the gain is improved and the bandwidth is also as wide as specified in our requirements.