Experimental Validation of the Feasibility of a Reconfigurable Square Spiral Antenna

This letter focuses on the experimental validation of a new square spiral antenna topology. The proposed topology can operate over an ultrawideband and be reconfigured into an array of smaller square spiral antennas. This offers a good surface efficiency and many advantages like an increase of both gain and directivity, a good circular polarization over the entire bandwidth, and the ability to reconfigure the radiation pattern. In the letter, the experimental validation is given for frozen states.