A 10-GHz sub-harmonic Gilbert mixer is demonstrated using GaInP/GaAs hetero-junction bipolar transistor technology. The local oscillator (LO) signal time-delay path in the sub-harmonic LO stage is compensated using the fully symmetrical stacked-LO doubler; therefore, the balance of the sub-harmonic LO stage, the radio frequency to intermediate frequency isolation, and IIP 2 are improved. The demonstrated 10-GHz sub-harmonic mixer achieves 10 dB conversion gain, IP 1dB of -12 dBm, IIP 3 of 2 dBm and IIP 2 of 33 dBm.
- 1/f noise
- Port-to-port isolation
- Sub-harmonic Gilbert mixer
- Time-delay-compensated doubler