DOUBLE-LAYERED CIRCULAR MICROSTRIP REFLECTARRAY ELEMENT WITH BROAD PHASE RANGE

In this paper, a double-layered microstrip re∞ectarray element is studied. The unit element consists of a circular patch sandwiched between two substrates and a cross-slotted circular patch placed on the top-most surface. The radii of the two circular patches as well as the cross-slot lengths are varied simultaneously for controlling the phase range and the gradient of the re∞ection phase angle. Study shows that the sensitivity of the re∞ection phase angle can be made slower by utilizing substrates with lower dielectric constants. The component performance is studied using a rectangular waveguide and good agreement is found between the simulation and experiment. A wide re∞ection phase range of 681.82 - with loss magnitude less than i1dB is achievable in the re∞ection phase angle. A complete parametric analysis has been conducted to study the re∞ection characteristics of the proposed re∞ectarray unit element.