US Patent 11232931 Intermodulation distortion mitigation using electronic variable capacitor

A matching network for a system having a non-linear load and powered by a first RF power supply operating at a first frequency and a second RF power supply operating at a second frequency. The matching network includes a first matching network section for providing an impedance match between the first power supply and the load. The matching network also includes a second matching network section for providing an impedance match between the second power supply and the load. A the first matching network section includes a first variable reactance, and the variable reactance is controlled in accordance with IMD sensed in the signal applied to the load by the first RF power supply. The variable reactance is adjusted in accordance with the IMD to reduce the detected IMD.