A study of a reflectarray topology based on coupled oscillator arrays using Substrate Integrated Waveguide technology

This paper presents the design of a reflectarray based on coupled oscillators, whose elements are active cavity-backed antenna oscillators. The cavity backed topology, implemented in Substrate Integrated Waveguide (SIW) technology, allows for a compact, single substrate implementation, and provides a means for the suppression of the undesired surface-wave modes and for heat dissipation. The coupling between adjacent oscillator elements in the array can be controlled by properly coupling their cavities, thus allowing for the implementation of power combining and beam scanning capabilities. A small prototype of a linear reflectarray of seven elements is designed by properly combining full-wave EM simulation for the radiating structure and nonlinear Harmonic Balance (HB) and transient analysis for the optimization of the oscillators and the study of the stability of its steady-state solutions.