Che-Chung KuoChun-Lin KuoChe-Jia KuoS.A. MaasHUEI WANG2018-09-102018-09-102008-04https://www.scopus.com/inward/record.uri?eid=2-s2.0-40549138237&doi=10.1109%2fTMTT.2008.919063&partnerID=40&md5=08ac973af7043e0fcb67925eb3595eb9In this paper, three monolithic star mixers using a new miniature dual balun are proposed. The first one is a double spiral transformer mixer, and the second one is a trifilar transformer mixer. Both of these are fabricated using a commercial GaAs pseudomorphic HEMT process. The third is a 3-D transformer mixer, which is fabricated using a commercial CMOS process. These mixers exhibit bandwidths over 2545 GHz (57%) with local oscillator isolations better than 20 dB. These star mixers are smaller than $(\lambda/6\times\lambda/6) $ for the mixer core area. Compared with traditional star mixers, these mixers demonstrate 80% size reduction, and achieve good performance with the smallest chip size among all star mixers using monolithic microwave integrated circuit processes. © 2006 IEEE.Balun; Diode mixer; Double-balanced mixer (DBM); Mixer; Monolithic microwave integrated circuit (MMIC); Resistive mixer; Spiral transformer; Star mixer; Transformerjournal article10.1109/tmtt.2008.9190632-s2.0-40549138237