Design And Implementation Of Metal-framed Mobile Phone Antennas

With the rapid development of mobile communication technology,significant changes for people's communication mode have been taken place in the past few decades.Mobile phones have become an essential electronic device in people's lives.In recent years,research on the ultra-thin metal-framed mobile phone antennas has been attracted much attention of scholars.How to integrate the 5G antennas into the metal-framed mobile phones is a worth studying subject.Thus,research on the metal-framed mobile phone antennas compatible with 4G and 5G is also of great practical value.Taking the metal-framed mobile phone antenna as the research object,a dual-band 8-element metal-framed mobile phone MIMO antenna and a multi-band metal-framed mobile phone antenna are designed and implemented in this thesis.The main contributions of this thesis are summerized as follows.1.An eight-element metal-framed mobile phone MIMO antenna sysytem covering 5G(Sub-6GHz)two bands is designed and implemented.The antenna system consists of eight elements with identical structures,which are placed vertically in pairs and arranged in four corners of the phone.The antenna element is simple in structure,its size is only 15.2mm×1.6mm×0.8mm,and its clearance width is only 2.4 mm.By using the HFSS electromagnetic simulation software,dimensions of the element are determined,and prototype of the MIMO antenna is fabricated and measured.The measured results indicate that the MIMO antenna system covers 3400-3600 MHz and 4800-5000 MHz frequency bands,the port isolations between any two adjacent elements are better than 10 d B,and their ECC values are less than 0.2.The eight-element metal-framed mobile phone MIMO antenna sysytem has good measured electrical performance indices.2.A metal-framed mobile phone antenna coveing LTE seven bands and 5G(Sub-6GHz)two bands is designed and implemented.The antenna consists of two different elements,in which the open slot is used as the basic structure.For one element,a band stop matching circuit is loaded near its feed port to improve its impedance matching,expanding its bandwidth such that the element operates in 824-960 MHz,3400-3600 MHz and 4800-5000 MHz frequency bends.For another element,by adjusting length of its microstrip feeding line,its impedance matching is effectively improved to cover 1710-2690 MHz band.The metal-framed mobile phone antenna has a simple structure,and its clearance width is only 4 mm,which accords with current development trend of mobile phones.By using the HFSS electromagnetic simulation software,dimensions of the antenna are determined,and the antenna prototype is fabricated and measured.The measured results indicate the metal-framed mobile phone antenna has good measured electrical performance indices.By loading two open slots and a simple matching circuit,the proposed antenna covers multiple bands compatible with 4G and 5G bands.This innovative design has practical application value in the context of current 5G network close deployment.