Performance improvement of reflectarrays based on embedded slots configurations

Abstract

An infinite reflectarray antenna in the X-band frequency range has been designed, and various slot configurations have been proposed to optimize the design of reconfigurable reflectarray antennas in the X-band frequency range. It has been demonstrated that the introduction of slots in the patch element causes a decrease in the maximum surface current density (J) and electric field intensity (E) and hence causes a variation in the resonant frequency of the reflectarray. Waveguide simulator technique has been used to represent infinite reflectarrays with a two patch unit cell element and scattering parameter measurements have been carried out using vector network analyzer. A change in resonant frequency from 10 GHz to 8.3 GHz has been shown for a slot width of 0.5W (W is the width of patch element) as compared to patch element without slot. Furthermore, a maximum attainable dynamic phase range of 314° has been achieved by using slots in the patch element constructed on a 0.508mm thick substrate with a maximum surface current density (J) of 113A/m and electric field intensity (E) of 14 kV/m for 0.5W slot in the patch element.