A Reconfigurable Planar Antenna Array (RPAA) with back lobe reduction

A novel structure of Reconfigurable Planar Antenna Array (RPAA) added with a microwave absorber is designed. This antenna is consists of two elements structure, which are the 16-element microstrip rectangular patch antenna structures (top structure) and the separated feed line structure (bottom structure). The unique property of this antenna design is that instead of fabricating all together in the same plane, the antenna's feeding network is separated from the antenna radiating elements (the patches) by an air gap distance. This allows reducing spurious effects from the feed line. This antenna is integrated with RF switches to produce the scanning beam pattern to desired direction. This can be done by controlling the switch state to either on or off mode. The additional material was proposed involves placing a microwave absorber material such as ECCOSORB@ (Emersion & Cuming Microwave Products, Inc., Randolph, and Mass) at the back of the top substrate. The ECCOSORB is useful for suppression of unwanted radiated field and thus improved the back lobe pattern at an average of 10 dB. The simulated results are presented to demonstrate the excellent performance of this antenna.