Research On Miniature Multi-frequency And Broadband Antenna For4G Mobile Phone

With the rapid development of mobile communication in recent years, more andmore requirements are needed in terms of handset antenna. Miniaturization,multi-frequency and broadband, which have been the dominant trend of mobile phoneantenna. At present, the electronically small antenna becomes the first choice formobile terminal because of its small volume, low profile and light weight, etc.This thesis discusses the basic theories and analytical methods of the mobilephone antennas, and summarizes the current techniques to realize miniaturization andmulti-band of the handset antenna. Meanwhile, according to the current hot topics anddesign trend of mobile phone antenna, the miniaturization and multi-band handsetantenna design ideas are studied and three novel miniaturization, multi-frequency andbroadband handset antenna are proposed.Among the three design schemes of miniaturization, multi-frequency andbroadband handset antenna, two designs adopt the principle of the PIFA antenna andanother antenna design uses coupling feed. In order to achieve miniature standard, thethree presented antennas use fold technique, which greatly reduce the volume ofantenna. The three antennas that can work at2G/3G/4G service bands haveadvantages of broadband, compact structure, simple feed and easy fabrication, etc.The six-band handset antenna can cover six bands: LTE700/AMPS800/GSM900/ISM(Bluetooth)/WLAN/WiMAX. While the eight-band handset antenna only adds one“C” shape patch based on six-band structure, which increase DCS1800and LTE2300bands. The third antenna with the coupling feed, which can work at eleven bands:LTE700/2300/2500, AMPS800, GSM900, DCS1800, PCS, UMTS, WiBro, ISM/Blue-tooth, WLAN, achieves wider frequency band compared with other two antennas.The three antennas have a good impedance matching after software optimizationsimulation. In addition, they all have broadband, high gain and omni-directionradiation patterns. All the antennas are fabricated and tested. The simulated andmeasured results agree well, these antennas are suitable for the qualification of mobilephone antenna.