Multibeam Antenna for Telecommunications Networks Using Cylindrical EBG Structure

We present in this letter the study of a multibeam antenna for telecommunication networks by using cylindrical electromagnetic band-gap (EBG) structures. The EBG structure behaves as a partially reflecting surface (PRS) and enhances the directivity of a simple radiating source. We begin by presenting the principle of the multibeam antenna, and then we present a first version, conceived to operate in WiMAX band [5.45.7] GHz. Simulation results of this antenna will show us that the strong mutual coupling between the different excitation sources of the EBG structure badly influences its performance. In order to reduce the mutual coupling, metallic walls are inserted between the excitation sources. Moreover, excitation sources have been changed to improve the radiation performance of the antenna. A prototype of the final antenna is fabricated to validate our simulation results, and the measurements results are compared to the simulated ones.