Cancellation of Passive Intermodulation Distortion in Microwave Networks

Passive nonlinearities in high-power transmit/receive wireless systems cause undesirable transfer of power from high-power transmit carriers to the receive band, causing levels of interference and distortion that can severely limit or debilitate the system. This paper proposes a method of cancellation that allows for reduction of nonlinear distortion due to passive nonlinearities in high-power wireless systems. We verify the method by experiment, resulting in almost 40 dB of cancellation of nonlinear distortion in a high-power radio frequency system, effectively eliminating the reflected passive intermodulation from the system.