A high efficiency and high power 165-180 GHz balanced doubler based on Schottky diode

In this paper, a high efficiency and high power 165-180 GHz balanced doubler based on the planar Schottky diode is presented. To maximize the efficiency of the doubler in the target frequency band, an in-band embedded impedance optimization method (IEIOM) is adopted. The method aims to extract the conjugate value of embedded impedances of the three-dimensional electromagnetic (3D-EM) model of the diode. Compared to the method of impedance optimization at a single frequency point using Load-Pull, the proposed method not only takes account for both conversion efficiency and bandwidth but also simplifies operation process. To verify the proposed concept, the doubler was fabricated and measured, which exhibits a conversion efficiency of 13%-46% at the 165-180 GHz band under 160-200 mW input power and a 90.88 mW peak output power with a 46% efficiency was measured at 178 GHz when the input power is 198 mW.