Reconfigurable leaky-wave antennas

In this chapter, an overview of the recent development of reconfigurable high-gain antennas is presented. These antennas range from reconfigurable Yagi antennas, reconfigurable reflectarrays and reconfigurable transmitarrays to reconfigurable PRS antennas. It is demonstrated that PRS antennas are able to reconfigure their frequency, polarization and radiation patterns with high realized gains. Compared with RA arrays, reconfigurable reflectarrays and transmitarrays, it is much easier for reconfigurable PRS antennas to achieve various reconfigurations with a simpler biasing network. In order to fully exploit the diversities of antennas in wireless communication and radar systems, compound reconfigurations of two or three antenna parameters are highly desired. However, there have been no reported products employing such combined RAs. Since PRS antennas have more freedom of parameters (a single feeding source/feeding source arrays and a PRS structure), the above challenge could be addressed by allocating different reconfigurations to different parts. As this work progresses, there is no doubt that fully reconfigurable PRS antennas will deliver significant benefits to practical wireless systems in future.