Fundamental Limitations on the Output Power and the Third-Order Distortion of Balanced Mixers and Even Harmonic Mixers

A theoretical comparison of the fundamental limitations on the output power and the third-order distortion of balanced diode mixers and even harmonic mixers is described in this paper. In the authors' previous work, formulas for the output power limitations of the mixers in a modulator operation were described. Using the described formulas, the output power and the third-order distortion of the mixers are calculated for a mixer operation and are represented as universal charts. Further, the closed-form formulas for the output power at a 1 dB gain compression and the intercept point of the third-order intermodulation products are presented. As mixers in a modulator operation, it is clarified that even harmonic mixers have a lower output power capability than balanced diode mixers. All the derived formulas were confirmed with experimental investigations at 100 MHz.