Design of a wideband 900 GHz balanced frequency tripler for radioastronomy

We report on the design of a fix-tuned split-block waveguide balanced frequency tripler working nominally at 900 GHz. It uses a GaAs Schottky planar diode pair in a balanced configuration. The circuit is fabricated with JPL membrane technology in order to minimize dielectric loading. The multiplier is bias-less to dramatically ease the mounting and the operating procedure. At room temperature, the expected output power is 50-130 μW in the band 800-970 GHz when the tripler is pumped with 4 mW. By modifying the waveguide input and output matching circuit, the multiplier can be tuned to operate at lower frequencies.