Adaptive beam steering base station antenna: Performances optimization of the reconfigurable EBG material

The aim of this paper is to present a new principle of beam steering using a controllable Electromagnetic Band Gap (EBG) based on the commutation between two complementary states of the metamaterial thank to PIN diodes along metallic wires for a wide frequency band including GSM, DCS and UMTS in place of classical feeding network including phase shifter, amplifier, .... After a short presentation of the beam steering principle and the antenna design, we will present the measurements of the electromagnetic characteristics of the antenna in several configurations (single or multibeam). These measurements will show the capabilities of this antenna to manage the radiation and some problems to steer the beam on all the working bands. Additionnal simulations, including lumped elements, will be presented in order to understand the radiation control problems, to iquestimproveiquest the performances of the EBG material and find the best RF characteristics of the PIN diodes to be able to manage the radiation on all frequency bands.