Measurement Of Electromagnetic Parameters Of Microwave Ferrite

In the microwave and low frequency accurate measurement of electromagnetic properties ofmaterials is an important issue. It has great significance for the development of basic research andapplied research of material. Based on the summary measurement methods of the electromagneticproperties of the material, at microwave frequencies, using cavity perturbation method, by studyingthe wave equation, wave in resonant cavity,we have a certain understanding for electromagneticmeasuring principle, through electromagnetic research in a rectangular resonator, we can get anelectromagnetic field expressions in a rectangular cavity to analyze and measure the performanceparameters of microwave ferrite. By measuring the difference of reflection coefficient containingand not containing the sample, then we can determine the electromagnetic parameters of materials:scattering parameters,the resonance frequency. we can calculate Q and Haccording to the VC++program,then the magnetic permeability of the material will get.Within1GHZ, ferrite measurement is still no uniform testing standards, mostly using lumpedparameter method directly. Passive magnetic ferrite components used in EMI filters, ferrite withcomplex magnetic permeability (CMP) versus frequency. In the frequency range from150kHz to30MHz when manufacturers often don’t give the complex magnetic permeability. Furthermore,certain measurement techniques require samples of special sizes and shapes. These passivedevices commonly used in EMI filter, we need to know the insertion loss of ferrite core. In thispaper,we proposed a more accurate core model to measure the complex magnetic permeability(CMP). Has been considered the leakage inductance parasitic capacitance of the inductor.Finally, the measurement is primarily caused by a vector network analyzer and we take adetailed error analysis.Simultaneously imperfect physical model,frequency error△f, sample lengthmeasurement error is also exist.