Patch end-Launchers-a family of compact colinear coaxial-to-rectangular waveguide transitions

A new family of structures launching the fundamental mode in rectangular waveguides is proposed. Individual or stacked cavity-backed patch antennas radiate into a rectangular waveguide, providing a good matching with a coaxial input over a wide frequency range. The configuration results in a very compact, colinear transition from a standard coaxial connector to a rectangular waveguide. The components have applications as general-purpose coaxial-to-rectangular waveguide transitions and are well suited for low-profile, phased-array antennas. Experimental results confirm the computational estimations of the proposed components' performance.