結構緊湊型雙頻微帶天線的設計.doc
結構緊湊型雙頻微帶天線的設計,摘 要 近年來,無線通信系統(tǒng)向著多功能、大容量、智能化的方向飛速發(fā)展。中國移動通信行業(yè)處于2g(第二代移動通信技術,second generation mobile communication technology)與3g(第三代移動通信技術,third generation mobile communicatio...
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內容介紹
此文檔由會員 龍飛網絡書城 發(fā)布摘 要
近年來,無線通信系統(tǒng)向著多功能、大容量、智能化的方向飛速發(fā)展。中國移動通信行業(yè)處于2G(第二代移動通信技術,Second Generation Mobile Communication Technology)與3G(第三代移動通信技術,Third Generation Mobile Communication Technology)共同飛速發(fā)展階段,移動通信用戶數目急劇增長,使得通信系統(tǒng)不斷更新和擴容。為了減小無線通信中的干擾,降低成本,同時滿足多系統(tǒng)、多功能的通信要求,實現多系統(tǒng)共用和收發(fā)共用,要求天線能在不同的工作頻段下工作。考慮到既要滿足上述特性,又要適用于工業(yè)化生產和實際的應用,我們需要一款結構相對簡單、低剖面、機械性能好、易于集成的天線,因此多頻微帶天線是非常合適的選擇。
微帶天線是二十世紀七十年代初期研制成功的一種新型天線,它具有許多優(yōu)點:體積小,重量輕,低剖面,制造簡單,成本低;易于和微帶線路集成;易于實現線極化和圓極化等。因此近十幾年微帶天線得到了廣泛的研究和發(fā)展,各種新型微帶天線結構層出不窮,應用也日益寬廣,目前廣泛應用于個人移動通信、衛(wèi)星通信、直播系統(tǒng)(DBS)、全球定位系統(tǒng)(GPS)、車載系統(tǒng)等。在總結以往多頻微帶天線研究的基礎上,本文提出了一款結構緊湊型微帶天線設計。
本論文的工作重點在于設計小型雙頻微帶貼片天線。論文中提出了一種適用于移動通信系統(tǒng)的緊湊型雙頻微帶貼片天線結構,即在半圓貼片結構上用微帶線饋電半圓環(huán)結構實現雙頻工作。該天線具有剖面低,結構簡單,容易加工,成本低,易于和微帶線電路集成,便于工業(yè)化生產等優(yōu)點。借助三維電磁仿真軟件Ansoft HFSS(High Frequency Structure Simulator),對雙頻微帶天線進行了仿真。得到該天線具有兩個工作頻帶,其中心頻率分別在0.9GHz和1.8GHz。
利用微波暗室和安捷倫網絡分析儀等現代的測量儀器,對天線實際工作性能進行測試。經測試,本文所設計的多頻微帶天線有兩個工作頻帶,其中心頻率分別為0.9GHz和1.8GHz。天線在兩個中心頻率處具有較深的諧振深度,良好的天線增益以及對稱的輻射方向圖。該天線可以應用于移動通信系統(tǒng)中。
關鍵詞:2G、3G通信網,移動通信系統(tǒng),多頻,微帶天線
Abstract
In recent years, wireless communication system has developed rapidly and has shown the trends as multi-functional, large-capacity, intelligent. Mobile communication industry in China is now in the 2G (Second Generation Mobile Communication Technology) and 3G (Third Generation Mobile Communication Technology) environment. The rapid growth of the number of mobile communication users update and expand the communication system. In order to reduce the interference in wireless communications, to reduce costs and meet the requirements of multi-systems and multi-functions, meanwhile, to realize the multi-systems and transceiver sharing, an antenna should work in different operating frequencies. For not only satisfying above properties, but also meeting the application of industrial production, we need a kind of antenna which has a relatively simple structure, a low profile, good mechanical properties, and it should be easy to be integrated. So a multi-frequency microstrip antenna is a very suitable choice.
Microstrip antennas were a new type antennas fabricated successfully in the early 1970s. They have some attractive features such as light weight, small volume, low profile, and low production cost. They also can be easily integrated with microwave integrated circuits and easily made into dual-frequency and dual-polarization antennas. So they have been researched and developed widely in the recent twenty years. All kinds of new microstrip antennas structures emerged in endless. They have been used widely in personal mobile communication, satellite communications, direct broadcast system (DBS), global positioning system (GPS) and vehicle carrying system and so on. Based on previous research works on multi-frequency antennas, this paper proposed a low-profile dual-frequency microstrip antenna.
First of all, the paper focused on this low-profile microstrip antenna. The dual-frequency is generated through a half-ring structure and a half-circular patch element. The antenna has features as low profile, simple structure, easy to be processed, low cost, easy to be integrated, and easy to be used in industrial production. By using Ansoft HFSS (High Frequency Structure Simulator), the subject of microstrip antenna is simulated. Simulation and measurement results show that the proposed antenna works at 0.9 GHz and 1.8 GHz.
By using microwave anechoic chamber and Agilent network analyzer we have tested the antenna's performance. Test results show that the multi-frequency microstrip antenna which designed in this paper has two working bands, the center frequencies are located in 0.9GHz and 1.8GHz, respectively. At the two center frequencies, the proposed antenna has deeper resonance depth, good antenna gain and symmetric radiation pattern. The antenna can be applied in a mobile communication system.
Key words: Wireless LAN, 2G, 3G communication network, Mobile communication system, Multi-frequency, Microstrip antenna
目 錄
第一章 緒論 1
1.1 研究背景及意義 1
1.2 多頻微帶天線國內外研究現狀 2
1.3 研究目標及主要工作 2
1.4 本文的主要研究成果和內容安排 3
1.4.1主要創(chuàng)新成果 3
1.4.2組織結構 3
微帶天線基本理論 4
2.1 微帶天線的基本特性 4
2.1.1 微帶天線的定義及結構 4
2.1.2 微帶天線的優(yōu)點及缺陷 4
2.2微帶天線的輻射原理 5
2.3傳輸線模型理論 7
2.3.1微帶線開路終端的輻射 8
2.3.2矩形微帶天線的分析 10
2.4圓形貼片腔模型理論 12
2.4.1內場 12
2.4.2輻射場和方向圖 17
2.4.3輸入阻抗和品質因素 19
2.4.4帶寬、效率和方向系數 22
2.5饋電方法 23
2.5.1微帶線饋電 23
2.5.2同軸線饋電 23
2.5.3共面波導饋電 24
一款結構緊湊型雙頻微帶天線設計 26
3.1 微帶天線介質基片材料的選擇 26
3.2 天線結構的設計 27
3.2.1天線尺寸的估算 27
3.2.2天線饋電方式及饋電位置的估算 28
3.3 天線仿真 29
3.3.1天線模型的仿真校正 29
3.3.2天線模型的仿真結果分析 30
3.4 微帶天線相關參數影響分析 33
3.4.1半圓環(huán)貼片半徑R1的影響 33
3.4.2半圓貼片半徑R2的影響 35
3.4.3饋電線長度L1與寬度W1的影響 35
3.5 天線測量及結果分析 36
3.5.1天線測量環(huán)境簡介 36
3.5.2測量儀器介紹 36
3.5.3天線測量結果 36
3.6 小結 37
結束語 38
4.1本論文的主要工作和創(chuàng)新點 38
4.2未來工作的展望 38
參考文獻 39
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