Conception et Réalisation d’Antennes Reconfigurables

Abstract

In this thesis we describe novel approaches in designing reconfigurable antennas. The proposed reconfigurable layouts are intended for integration into compact UWB communication systems and are characterized by their low profile and easy fabrication processes. Initially, the project was to design et implement some reconfigurable antennas based on conductive polymers. As a result, the first part of this thesis provides an advanced literature survey as well as an investigation on the use of tunable permittivity or conductivity in designing antennas based on conductive polymers. The second part of this thesis reports on the design of planar reconfigurable UWB antennas with interference filtering capabilities. Firstly, a planar monopole UWB reconfigurable antenna has been designed showing filtering capabilities in three narrow bands which could potentially interfere in this particular region of the spectrum. Reconfigurability allows the antenna to match to any interference cases. The presented design uses low-cost FR 4 substrates known for being light. Secondly, an extremely compact UWB single-sided reconfigurable designed antenna is described. Unlike the previous antenna, the reconfigurable filtering circuit has been exclusively implemented in the ground plane rather than in the radiating patch in order to optimize the radiation performance of the antenna. By doing so, the new design is cost effective, allowing interferences’ filtering at the antenna level rather than at a later stage and avoids complex biasing control antenna circuitry