Recent progress in antennas with an EBG reflector and antennas with periodically arrayed loops

A low-profile curl antenna with an EBG reflector has a relatively wide input impedance bandwidth. Low-profile equiangular- and Archimedean-spiral antennas, each backed by an EBG reflector, have a wider input impedance bandwidth than the curl. A low-profile inverted F antenna above an EBG reflector radiates a tilted beam. An array composed of inverted F antennas combined with switching circuits has a beam that can be scanned. A layer of periodically arrayed loops transforms the axial beam of an antenna into a tilted beam with high directivity.