Читать книгу Introduction To Modern Planar Transmission Lines - Anand K. Verma - Страница 157

The relative permeability matrix of a gyromagnetic ferrite medium is given below:

(4.2.12)

In the above equations, H₀ is the biasing magnetic field in the z‐direction, M_s is the saturation magnetization, and the parameter γ is the gyromagnetic ratio. Again the cross‐coupling factor jκ is responsible for the gyration property of the relative permeability of a medium. The permeability function shows a singularity at the frequency ω = ω₀. It is suppressed in the presence of losses. In the case of unbiased and demagnetized ferrite, H₀ = 0 and M_s = 0 leading to k = 0 and μ_r = 1. The ferrite, in this case, acts as a dielectric medium with permeability μ = μ₀.