Numerical Modelling of Unbiased Microstrip Circulators Based on Magnetic Nanowired Substrate: Use of a ferrite-equivalent model

An existing unbiased microstrip circulator based on magnetic nanowired substrate is modelled with a numerical electromagnetic simulation software. Although an analytical analysis is possible for basic Y-junction circulators, numerical modelling is required for more advanced design, but has to be validated on known devices. Numerical modelling of a single nanowire would imply a nanometer scale mesh. Because the ciculator uses millions of them, each nanowire of the whole design cannot be meshed with the current hardware capabilities. The unbiased nanowired substrate is thus defined as a biased ferrite-equivalent substrate. Input parameters of the ferrite-equivalent model are derived from previous work and new hypotheses about the physical properties of the nanowired substrate. Comparison between experimental data and simulation results validates the hypotheses.