A Waveguide Reconfigurable Multiband Terahertz Frequency Doubler Using Choke Flange Technology

In this article, a novel waveguide reconfigurable Schottky diode-based frequency doubler with tunable multiband high efficiency output is proposed and demonstrated. The multiband frequency output is achieved by reconfigurable input waveguide matching and cross-band output circuits matching. In the doubler, the whole cavity is composed of two parts: reconfigurable input matching waveguide cavities and coused main circuit associated with the coused cavity. These reconfigurable cavities are designed to match input impedance for corresponding band. The coused main circuit is adopted by weight optimization to fulfill output match of multiband. Then, the reconfigurable cavity is assembled into doubler through reduced-height waveguide choke flange, which aims to alleviate the assembly interconnection losses. Sample of the frequency doubler, operating at 170, 183, and 220 GHz, has been demonstrated based on this prototype. Measured results indicate that, the peak efficiencies of three bands are 38%, 34.5%, and 22.3%, respectively, with a total tunable operating bandwidth of 50 GHz.