A highly linear double balanced Schottky diode S-band mixer

A high-level double balanced SiC Schottky diode mixer in SiC monolithic microwave integrated circuit (MMIC) technology has been designed, processed and characterized. The mixer is a single ended in- and output circuit with coupled transformers as baluns to enable a compact design, resulting in a total area of 2.2/spl times/2.2mm/sup 2/. The mixer has a maximum IIP/sub 3/ of 38dBm and IIP/sub 2/ of 58dBm at 3.3GHz, and a typical P/sub 1 dB/ of 23dBm in the S-band. The minimum conversion loss was 12dBm at 2.4GHz. The high power operation of the mixer shows that SiC MMIC can perform well in high microwave radiation environments.