Compact Planar Resonator Arrays

Abstract

Compact planar arrays based on resonators generally of the Fabry-Perot type, have, as with reflectarrays, their origins in the technology of planar periodic surfaces sometimes referred to as frequency selective surfaces (FSS) or metamaterials. The cavity resonator antenna (CRA) which is arguably better known as a partially reflective surface antenna (PRS) can be a source of very compact geometries. With its quite surprising potential for high directivity in a compact package, the PRS antenna has recently been attracting growing interest. Furthermore, despite its low to moderate bandwidth the gain advantages continue to motivate the use of PRS antennas in space applications, in remote sensing, or in satellite communications. The introduction of passive periodic surfaces such as frequency selective surfaces, metamaterials and leaky-wave surfaces into the CRA package has enlarged the range of possible applications by offering the potential of introducing inexpensive electronic beam steering into antennas in a compact package, making mobile communications roles, and applications in ‘wireless’ networks, seem distinctly possible.