REFLECTARRAYS OF RECTANGULAR MICROSTRIP PATCHES FOR DUAL-POLARIZATION DUAL-BEAM RADAR INTERFEROMETERS

Microstrip reflectarrays consisting of rectangular patches are investigated for application in space-based dual-polarized dual-beam radar interferometers. For nadir looking beams the angle of incidence of feed radiation in each patch is nominally 45˚. In such an application, square-patch reflectarrays can be designed for only one polarization with a sacrifice in performance in the other whereas reflectarrays consisting of rectangular patches may be designed for both polarizations, thereby improving their radiation performance. Piecewise planar parabolic reflectarrays consisting of square patches exhibit poor scan performance in tilted configuration. It is shown that with the use of rectangular patches in such a reflectarray one can design two beams of different polarizations for two offset feeds, thereby providing significant improvement in bandwidth and radiation performance.