Multiband Design And Research Of Built-in Terminal Antenna

Multi-frequency and miniaturization of built-in terminal antenna has been a hot topic in recent years.The development of wireless communication technology also puts forward higher requirements for antenna design,so how to realize multi-frequency coverage in a limited space is one of the problems facing terminal antenna.In this paper,three kinds of multi-frequency antennas are designed by means of multi-branch and so on,aiming at the problem of multi-frequency realization of the built-in terminal antenna.The research contents of this paper mainly include the following aspects.1.this paper first describes the background and significance of mobile terminal antenna,introduces two kinds of commonly used built-in terminal antenna: planar monopole antennas,planar inverted F antenna,and comparing their respective characteristics and the performance index,finally summarizes the implementation of mobile terminal antenna miniaturization,multiband,broadband technology.2.For the multi-band antenna,two built-in multi-band monopole antennas and one built-in inverted f-type antenna are designed,the design idea and flow of antenna are described in detail,and the influence of the change of antenna structure size parameters on the performance of the whole antenna is discussed.Finally,the three antennas have achieved good impedance and bandwidth.The bandwidth defined by S11?-6db covers GSM,DCS,PCS,UMTS,LTE and other communication frequency bands,and has good omni-directional property within the frequency band,which is suitable for modern builtin terminal devices and has good application value.3.Finally,the paper focuses on the application test of five common built-in terminal antennas on different terminal devices.By analyzing different terminal equipment on the attenuation of the antenna performance is likely to cause,tested antenna in detail under different status of passive and active performance,debugging,optimized and combined with network analyzer,discusses the structure and components around the antenna terminal device itself brings to the antenna performance interference;Finally,by adjusting the antenna shape and improving the environment around the antenna,the interference degree of peripheral devices to the antenna sensitivity was reduced,and the radiation performance of the whole antenna was improved.