Computer-aided design of microwave frequency doublers using a new circuit structure

A circuit structure for microwave frequency doublers is presented. It has been used in the design of a MMIC (monolithic microwave integrated circuit) doubler. Its major advantages are effective suppression of the unwanted odd-order harmonics and conversion gain to the desired second harmonic. These advantages have been demonstrated by computer simulation and further verified by measured results for the MMIC circuit. The circuit can be used in both balanced and unbalanced output configurations, without requiring baluns or transformers. The fundamental frequency suppression was found to be over 50 dB, while better than 3 dB conversion gain was achieved.<
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