發(fā)布時間：2018-09-03 13:59

【摘要】：隨著第三、四代移動通信網(wǎng)絡的成熟與普及,移動終端設備得到快速的發(fā)展,天線作為終端設備接收無線信號的前端部件,也發(fā)生著巨大的變化,隨著手機功能增多,金屬機身流行,以及MIMO天線技術的應用,終端天線不僅要滿足小型化、寬頻化、多頻帶的技術要求,而且還要克服金屬機身對天線輻射性能的惡化影響,設計具備多種功能的多天線(multi-antenna)系統(tǒng)。根據(jù)上述需求與挑戰(zhàn),本文提出了三款共用金屬邊框的終端MIMO天線設計方案。首先,本論文分析了終端天線發(fā)展以及國內(nèi)外研究現(xiàn)狀,總結了終端天線設計所面臨的挑戰(zhàn),以及本論文的研究重點和創(chuàng)新之處。然后結合天線理論知識,對用于終端MIMO天線設計的常用天線形式、實現(xiàn)小型化、寬頻帶方法、MIMO天線性能衡量指標以及實現(xiàn)MIMO天線高隔離的常用方法進行歸納。其次,本論文提出一款共用金屬邊框的雙WIFI天線,金屬邊框同時作為兩天線的主要輻射結構,利用去耦結構提高天線單元之間的隔離度,隨后對天線的S參數(shù)、輻射特性、MIMO分集特性進行測試。最后通過在單元天線1饋電端口設計匹配網(wǎng)絡,有效增加天線單元1工作帶寬,實現(xiàn)WIFI/GPS同時覆蓋。再次,本論文提出一款共用金屬邊框的七頻可重構MIMO天線。天線采用U形微帶線耦合饋電方式,激勵起由金屬邊框與地板構成的金屬環(huán),利用環(huán)天線多模諧振特點以及開關可重構技術,實現(xiàn)天線四種工作狀態(tài)切換,最終覆蓋七個通信頻段。根據(jù)環(huán)天線電流分布特性,通過合理設計天線位置,實現(xiàn)MIMO天線在整個工作頻帶內(nèi)具有較好的隔離度。文章從電流分布圖、重要參數(shù)討論對天線工作原理進行詳細分析,最后通過加工測試,對天線的輻射特性與分集特性進行了評估。最后,本論文提出了一款用于完整金屬邊框終端的多天線系統(tǒng),該天線系統(tǒng)既包含LTE七頻天線又包含雙頻WIFI MIMO天線,三副天線共用完整金屬邊框作為天線結構進行輻射。LTE天線通用匹配網(wǎng)絡對端口進行阻抗匹配,實現(xiàn)七個頻段覆蓋(GSM850/900/GSM1800/1900/UMTS2100/LTE2300/2500),WIFI天線采用被動可重構原理,實現(xiàn)2.4GHz與5.8GHz雙頻段覆蓋。隨后對天線的工作原理進行了詳細分析,通過對天線模型加工測試,結合天線的仿真結果進行對比分析,最終得到工作帶寬、隔離度、輻射效率、MIMO天線分集特性均滿足設計要求共用金屬邊框的終端天線系統(tǒng)。
[Abstract]:With the maturity and popularity of the third and fourth generation mobile communication networks, mobile terminal equipment has been rapidly developed. As the front-end component of terminal equipment receiving wireless signals, antenna has also undergone tremendous changes. With the increase of mobile phone functions, the popularity of metal fuselage, and the application of MIMO antenna technology, the terminal antenna should not only meet the needs of miniaturization and widening. To overcome the deterioration of radiation performance caused by metal fuselage, a multi-antenna system with multiple functions is designed. According to the above requirements and challenges, three MIMO antenna design schemes with common metal frame are proposed in this paper. Firstly, the development of terminal antenna is analyzed. Then, combined with antenna theory knowledge, the common antenna forms used in terminal MIMO antenna design are realized, including miniaturization, broadband method, performance measurement index of MIMO antenna and high isolation of MIMO antenna. Secondly, a dual WIFI antenna with a common metal frame is proposed. The metal frame is used as the main radiation structure of the two antennas. The isolation between the antenna elements is improved by using the decoupling structure. Then the S parameters, radiation characteristics and MIMO diversity characteristics of the antenna are tested. Thirdly, a seven-band reconfigurable MIMO antenna with a common metal frame is proposed in this paper. The antenna is fed by a U-shaped microstrip line to excite a metal ring composed of a metal frame and a floor. The multi-mode resonance characteristics of the ring antenna are utilized. According to the current distribution characteristics of the ring antenna, the MIMO antenna has a good isolation degree in the whole working frequency band by designing the antenna position reasonably. This paper discusses the working principle of the antenna in detail from the current distribution diagram and the important parameters. Finally, the radiation and diversity characteristics of the antenna are evaluated by processing and testing. Finally, a multi-antenna system for the terminal with complete metal frame is proposed, which includes both LTE seven-band antenna and dual-band WIFI MIMO antenna. Line radiation. LTE antenna general matching network matches the impedance of the port to achieve seven band coverage (GSM850/900/GSM1800/1900/UMTS2100/LTE2300/2500). WIFI antenna uses passive reconfigurable principle to achieve 2.4 GHz and 5.8 GHz dual band coverage. Then the working principle of the antenna is analyzed in detail, and the antenna model is processed and tested. Comparing with the simulation results of the MIMO antenna, the bandwidth, isolation, radiation efficiency and diversity characteristics of the MIMO antenna can meet the design requirements of the terminal antenna system with a common metal frame.
【學位授予單位】：電子科技大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TN820

【參考文獻】

相關博士學位論文 前1條

1 李健鳳;MIMO手機天線研究[D];華南理工大學;2013年

相關碩士學位論文 前2條

1 陳忠祥;用于LTE智能機的MIMO天線技術研究[D];電子科技大學;2015年

2 孫靜;小天線設計與測試方法研究[D];上海交通大學;2008年

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本文編號：2220172