An Intermodulation Distortion Suppression Selfinjecting Real-Time RF Signal Processing Feedback Loop

This paper presents an approach to suppress third order intermodulation (IMD3) products by designing a real-time RF signal processing second harmonic self-injection feedback loop. Harmonic separation network and RF signal processing network form a second harmonic self-injection feedback loop in RF active device circuit to cancel out IMD product. To verify the proposed design concept, a prototype is designed, fabricated, and validated both in simulation and measurement. The measurement results align well with circuit EM simulation to demonstrate propose design approach.