Complex permittivity and permeability of barium and strontium ferrite powders in X, KU, and K-band frequency ranges

Abstract

This paper presents accurate results for the complex permittivity, ε=ε′−jε″ and permeability, μ=μ′−jμ″ of barium ferrite powder (BaFe12O19) and strontium ferrite powder (SrFe12O19), in the frequency range from 8.0to26.5GHz. The complex permittivity and permeability are determined via the waveguide transmission/reflection (TR) technique and the waveguide cavity resonator (CR) technique at 25°C and relative humidity <75%. Measurements reveal that the real permittivities of BaFe12O19 and SrFe12O19 are, respectively, 2.497<εBa′<2.678, and 2.597<εSr′<2.712. BaFe12O19 has an average real permeability μBa′=1.078 and SrFe12O19 has an average real permeability μSr′=1.063. The imaginary permittivities are respectively εBa″<0.081 and εSr″<0.077. The imaginary permeabilites are respectively μBa″<0.095 and μSr″<0.106.