An Accurate Method for Synthesis of Reflecting Elements to Design Wideband Reflectarray Antenna

This paper presents an accurate method for synthesis of true time delay (TTD) reflecting elements to design wideband reflectarray (RA) antennas. In doing so, primarily the conventional phase distribution formulation of RA is modified to accommodate the design of resonant reflecting elements based on TTD technique. An accurate circuit model is then presented to realize the linear reflection coefficient phase of the reflecting elements of the RA antenna using the continued fraction theory. Finally, the equivalent circuit models of reflecting elements are implemented via multilayer frequency selective-surface structures. The RA antenna is designed and fabricated to operate in the X-band frequency. Stable aperture phase efficiency of about 80% and stable radiation patterns throughout the operating frequency band, confirm the accuracy of the proposed method.