The Stoichiometric Ratio Z The Research And Application Of Hexagonal Ferrite

With the rapid development of mobile communication technology,the antenna thatis used in personal mobile terminal is developing to miniaturization,multi-frequency.Highdielectric materials are used as a loaded media of the antenna,which can effectivelyreduce the size of the antenna.the ferrite possesses permittivity and permeability,so itwas proposed to miniaturize the very-high frequency (VHF) antenna.In this article the non-stoichiometric Z-type ferrites were investigated and theferrite was used to miniaturize the antenna,and the Z-type ferrite antenna for the mobilephone application was investigated.The main results are as follows:1. The effect mechanisms of Ba excess on Z-type hexagonal ferrite were investing-ated,The effects of calcination temperatures and sintering temperatures were studiedalso.2.The effect mechanisms of Co excess on Z-type hexagonal ferrite were studied,itwas found that small amounts of Co excess improve electromagnetic performance,forCo2Z type hexagonal ferrite with too much Co excess multi-phase mixtures were obtain-ed, which reduces the electromagnetic properties of materials.3.Ba deficient effect mechanisms of Z-type hexagonal ferrite were investigated,theresults show that:for barium deficient samples multi-phase mixtures were obtained,thatreduces the saturation magnetization of the material and also reduces the initialpermeability of the material.4.Co deficient effect mechanisms of Z-type hexagonal ferrite with were studied,experimental results show that:the lack of a certain amount of Co makes the materialgrain size become bigger and increase the permeability of the material,the lack of excessCo,so that the grain size becomes small and it decreases the magnetic permeability anddielectric constant.5.A T-DMB mobile antenna which work at175MHz~210MHz was made by usingZ-type hexagonal ferrite as a loaded media,and the performance of the antenna designedby using HFSS simulation software was tested.The results showed that:using Z-type hexagonal ferrite antenna as a loaded media conducive to the miniat-urization ofmobilephone antenna.