Design Of Compact Multi-band Mobile Phone Antennas

With the high-speed development of wireless communications,smart phones have been widely used.From the initial mobile phones to today's powerful smart phones,the demand for muti-function mobile phones is also increasing.The emergence of ultra-thin smart phones and smart phones with fullvision display in recent years made the study of low-profile mobile phone antennas and mobile phone antennas with small clear extremely imminent.With the increase of mobile phone's functions,the reduction of the profile,and the increase of the screen's area,the difficulty to design the mobile phone antenna is also increasing.The thesis mainly makes study of low-profile mobile phone antenna and mobile phone antenna with small clear.Based on the analysis of the technical problems that need to be used in design of mobile phone antennas,low profile and small clear antennas are studied in this paper.Firstly,the thesis introduces the research background,development history of the mobile phone antennas,the main forms of the mobile phone antennas,the technical problems of miniaturization and multi-frequency needed in antenna design,the main performance indicators of the mobile phone antenna,required environment when the mobile phone antennas tested.Secondly,two low-profile mobile phone antennas were designed.The first antenna is a low-profile seven-band mobile phone antenna.The antenna utilizes multiple-radiating stubs technology,folding radiation stubs technology,also using loading technology to improve the antenna to cover seven operating bands.The designed antenna has a good performance and is suitable for the mobile phone equipment.The antenna also has a good engineering utilization value.Based on the first antenna,an eight-band low-profile mobile phone antenna was designed using multi-band technology.By using multi-branch technology,folding radiation branch technology and loading technology,the antenna covers eight frequency bands to meet the 4G communication.Thirdly,a small clear miniaturized mobile phone antenna was designed for the mobile phones with fullvision display.Compared with the small clear antenna which is studied in recent years,this antenna's clearance is very samll.The designed antenna's clearance is only 5mm and the height of this antenna is 3.8mm.This antenna covers the eight operating bands.The test results show that the antenna can be well used in the mobile phones with fullvision display.