A broadband and miniaturized V-band passive MMIC frequency doubler

The paper presents a wideband V-band passive MMIC frequency doubler. It consists of input match circuit, two balanced diodes and a passive balun. The input match circuit is mainly consisted of parallel capacitor to ground, which could be taken as input match. Two balanced diodes are constructed by HEMT (High Electron Mobility Transistor) where drain and source have been short-circuited. The passive balun adopts a novel, but very simple structure, which makes two-way signals attain 180° phase difference in a very wide frequency range. The doubler is simulated in ADS and is fabricated in the OMMIC process. The measurement results show that this doubler has relatively low conversion loss, about from 10dB to 13dB when input power level is bigger than 10dBm. The doubler also has favorable suppression over 1/2 and 3/2 spurs, which are better than 20dB, from 40GHz to 75GHz output frequencies. In addition, the doubler occupies little area, only 0.6mm2, and so saves much cost.