Ka-band Broadband Frequency Multiplier Design

Ka-band broadband millimeter-wave quadrupler is designed and developed in this paper. The input and output ports are SMA and WR28 respectively. This quadrupler is realized by the structure of doubler-amplifier-doubler. The quadrupler is composed of 13-20Ghz-band broadband doubler, broadband amplifier and Ka-band broadband doubler.Theory basis is provided with characteristic of nonlinear device connection in series and parallel and series-parallel for this paper. The former wideband doubler is manufactured by using a novel planar bilateral coupled microstrip balun and a shottky diode pair in series. The drive amplifier is manufactured using MMIC. The latter doubler is realized by a solid circuit which consists of suspend stripline low pass filter, coplanar waveguide impedance conversion circuit, shottky diode pair in series-parallel, finline impedance conversion and gradual change finline. The whole circuit is designed and optimized by Serenade and HFSS of Ansoft Corporation.The testing result of former doubler is that the conversion loss is below 13dB and the harmonic suppress is higher than 15dB, and the one of broadband amplifier is that the conversion gain is higher than 14dB, which is up to the demand. All parts of Ka-band doubler circuit are analyzed and designed in theory and some are emulated by software.