Rf Ferrite Materials And Broadband Devices

With the development of information technology in the 21st century, the devices to miniaturization, broadband, anti-EMI technology is increasingly obvious and put forward higher requirements for the performance of the materials. The Co2Z-type hexagonal ferrite has become an ideal material for application of high-frequency inductors, broadband devices and anti-EMI components, as soft magnetic materials with high initial permeability, high Q value, high cut-off frequency. In this paper, the Co2Z-type high-frequency soft magnetic materials and application of broadband devices have been studied for the development trend.In this thesis, the Co2Z-type hexagonal ferrite materials with high-frequency and high-Q were prepared by the traditional oxide methods. Experiments with oxygen atmosphere sintering as the main line, through the experimental analysis of the phase structure, microstructure and electromagnetic properties of ionic replacement, Fe2O3 relative content, calcining temperature and sintering temperature etc and comparison with the materials sintered in air. The results show that changing the sintering atmosphere can effectively improve the high-frequency magnetic properties of materials, the real part of permeability of material is 8.2, Q factor is 15.05,μ′Q is 123.41 at 1GHz; the initial permeability is 5.99; the cut-off frequency is above 1.8GHz; the resonance frequency is above 1.8GHz at the pre-sintering temperature of 1260℃and the sintering temperature of 1220℃in Oxygen atmosphere.The Co2Z-type hexagonal ferrite materials are widely used at high-frequency fields. In this paper, the Co2Z soft magnetic materials were used as magnetic cores to design and manufacture a broadband coaxial cable power combiner/divider. The design and fabrication of power combiner/divider is mainly based on transmission line transformers network, based on theoretical calculation, formula derivation and proof. With the theory of transmission line transformers,the main part of design process of the device such as power combiner/divider network, impedance matching network, magnetic core etc were analyzed. According to the design requirements of the device, the design proposal and design parameters were determined and the entire process of design and fabrication was completed. Finally, achieved relative good results through the test of the device object. And the certain superiority had been verified to use the Co2Z-type hexagonal ferrite materials as magnetic cores from a practical experiment of the power combiner/divider.