ADS Design Guide for FSL
FSL device structures
Microstrip line based FSL
Co-planer waveguide(CPW) based FSL
Two FSL device structures are considered here. The first one is microstrip line based FSL device, where a YIG thin film is sandwiched by a signal strip and a ground plane. The second structure is CPW based FSL, where the YIG thin film is placed beneath the signal strip and two ground planes. The main difference is that for CPW-FSLs, the magnetic field distribution is not uniform, compared with MLIN-FSL case. As a result, different circuit model is needed to account for such field nonuniformity.
Modeling approach
A compact nonlinear circuit model is developed for frequency-selective limiters (FSLs) based on thin film magnetic materials. The model contains three-port spin units that represent the dynamic spin precession behaviors. They are derived rigorously from the Landau-Lifshitz-Gilbert (LLG) equation. Afterwards, the three-port spin units are combined with external circuity to represent the coupling between the RF signal in the form of electromagnetic (EM) waves and the spin waves.
Related publications
H. Cui Z. Yao and Y. E. Wang, "Coupling Electromagnetic Waves to Spin Waves: A Physics-Based Nonlinear Circuit Model for Frequency-Selective Limiters," in IEEE Transactions on Microwave Theory and Techniques, vol. 67, no. 8, pp. 3221-3229, Aug. 2019, doi: 10.1109/TMTT.2019.2918517.
Mason Fordham, Rüstü Umut Tok, Han Cui, Yuanxun Ethan Wang. “A Nonlinear 3-D Equivalent Circuit Model for Ferromagnetic RF Devices”. Government Microcircuit Applications & Critical Technology Conference (GOMACTech), 2021.
Qian Gao, Mason Fordham, Yuanxun Ethan Wang. " A Compact Model for Frequency-Selective Limiters with Strong Field Nonuniformity". Government Microcircuit Applications & Critical Technology Conference (GOMACTech), Miami, FL, Mar. 21-24, 2022.
Design guide functions
CPW-FSL design guide ADS schematic files' functions:
MLIN-FSL design guide ADS schematic files' functions:
Sample simulation file & simulation result:
MLIN-FSL insertion loss simulation schematic
Plot of insertion loss with input power sweeping
Design guide downloads & install instruction
Acknowledgement
This work is funded by DAPRA M3IC program.