Practical aspects of the characterization of ferrite absorber using one-port device at RF frequencies

The one-port-circuit impedance method has been used for study and development of novel materials for EW, such as absorbers, in electromagnetic noise suppressors, and current transducers. This method allows the electromagnetic characterization in the frequency range between 100 Hz and 100 MHz. The experimental arrangement implemented in the laboratory was validated using the data obtained from a Ni-Zn ferrite. Based on the expected values for the physical quantities and taking into account the dynamic measuring range of the equipment, it was verified that a limitation of the method is expected for low frequencies. The reliability of both the permeability and permittivity data was certified for frequencies higher than 10 kHz, which was justified from the impedance levels measured on the sample holder used. Discussions are made, about the method and about solutions for using the same in the whole frequency range of the equipment.