Quasi-optical planar arrays with FETs and slots

This work describes the design concept and experimental results for prototypes of two-dimensional quasi-optical power-combining arrays. Several different quasi-optical circuits were used to obtain the fundamental data for this study. How to incorporate the antenna input impedance into the active antenna circuit and how to analyze the strong coupling condition with two operating modes are addressed using large-signal analysis. Several circuit configurations are demonstrated, including a single active antenna operating at 9.3 and 24.0 GHz, a six-element linear power-combining array operating at 15.6 GHz, and four-element and sixteen-element two-dimensional power combining arrays operating at 10.4 and 7.8 GHz. Important characteristics such as antenna patterns and tuning ranges are discussed. The prospects for a two-dimensional monolithic quasi-optical power-combining array are discussed