A Two Dimensional Quasi-Optical Microwave Power Combining System Based On A Dielectric Slab

Hwang, Huan-Sheng A Two Dimensional Quasi-Optical Microwave Power Combining System Based On A Dielectric Slab Under the direction of Michael B. Steer A quasi-optical (QO) power combining system based on a two dimensional hybrid dielectric slab beammode waveguide (HDSBW) with solid-state devices is demonstrated. This 2D QO system can serve as a planar resonator or a planar amplifier system, in which active E-plane taper-slot antennas are embedded on the top surface or underneath the slab. The resonant frequencies and cavity modes of the slab resonator were investigated, and experimental free-running and injection-locked operations are shown and indicate that the 2D resonator is an excellent single-mode source. Impedance matching has been accomplished by studying the propagation constants and wave impedances in the HDSBW and the tapered horn. Theoretical result of the TE mode coupling between the horn and the HDSBW system is accomplished and agrees with the measured data. The active convexand concave-lens HDSBW systems with the MESFET/MMIC amplifier units were also implemented. Measurements of the amplifier gain and system gain, scattering loss due the lenses and antennas, and the surface fields of the combined power are shown, and provide the details of the designing methodology for the future planar QO power combiners. The radiation patterns of the metal-strip leaky-wave antenna located on the top of the passive HDSBW has been characterized. This antenna has the main beam scanning at 10 degrees per 1 GHz shift and can be used as the radiating end for the active HDSBW amplifier system.