[IEEE 2018 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications (IMWS-AMP) - Ann Arbor, MI (2018.7.16-2018.7.18)] 2018 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications (IMWS-AMP) - Nonlinear Equivalent-Circuit Model for Thin-Film Magnetic Material Based RF Devices

摘要： A nonlinear equivalent-circuit model is developed for thin-film magnetic material based RF devices such as frequency-selective limiter (FSL) and signal-to-noise enhancer (SNE). The ferromagnetic resonance is modeled by a RLC parallel circuit with parameters derived from Kittel’s equations. The nonlinear effect in magnetic material is represented by a pendulum model that predicts cross-frequency coupling as well as parametric oscillations of spins. The coupling of spin waves in different orders is also modeled by coupled nonlinear pendulum resonators with the exchange coupling between the spins represented by coupling inductors. The measurement results of a FSL in literature are used as a reference, and the model successfully predicts the threshold power level, nonlinear insertion loss, and frequency selectivity of the device.