【摘要】：漏泄波導(dǎo)與漏波天線已在無線通信系統(tǒng)中得到了廣泛應(yīng)用。近年來,隨著人們對無線通信要求的不斷提高,以及基于無線通信列車自動控制系統(tǒng)的發(fā)展,受限空間高效電波覆蓋問題受到重視,作為受限空間主要電波覆蓋手段的漏泄波導(dǎo)與漏波天線也因此成為研究重點。本文旨在研究適用于受限空間的具有高效電波覆蓋特性的新型漏泄波導(dǎo)與漏波天線,主要進行新型漏泄波導(dǎo)輻射特性分析、結(jié)構(gòu)設(shè)計、以及應(yīng)用中的環(huán)境適應(yīng)性研究；同時在漏泄波導(dǎo)基礎(chǔ)上研究適用于受限空間的圓極化漏波天線。研究工作對提高受限空間中的電波覆蓋性能,進而提升無線通信可靠性具有重要意義。 本文的主要工作和創(chuàng)新成果如下： 1.設(shè)計了一種漏泄圓波導(dǎo)結(jié)構(gòu),以便在高頻段代替漏泄同軸電纜、降低系統(tǒng)的傳輸損耗。在漏泄同軸電纜理論基礎(chǔ)上,進行了漏泄圓波導(dǎo)的輻射模式及遠(yuǎn)場特性分析,給出了耦合損耗與結(jié)構(gòu)參數(shù)的關(guān)系。結(jié)果表明,漏泄圓波導(dǎo)除了存在m0次空間諧波輻射外,也可以存在m≥0次空間諧波輻射,這是與漏泄同軸電纜不同的地方。 2.提出了一種利用全波數(shù)值結(jié)果求解漏泄圓波導(dǎo)傳播常數(shù)的方法,分析了漏泄圓波導(dǎo)歸一化傳播常數(shù)隨波導(dǎo)參數(shù)的變化關(guān)系。在此基礎(chǔ)上,利用曲線擬合方法給出了漏泄圓波導(dǎo)傳播常數(shù)的經(jīng)驗公式,為快速估算漏泄圓波導(dǎo)的傳播常數(shù)、截止波長和輻射模式提供了一種方便有效的方法。 3.提出了一種加脊漏泄圓波導(dǎo)結(jié)構(gòu),通過沿波導(dǎo)軸線方向加細(xì)金屬線的方法使得波導(dǎo)內(nèi)場結(jié)構(gòu)的極化方向保持不變,從而可以改善漏泄圓波導(dǎo)的長距離傳輸特性。此外,針對復(fù)雜通信環(huán)境對同一波導(dǎo)不同地方耦合量變化的要求,提出了一種貼片漏泄圓波導(dǎo)結(jié)構(gòu),可以通過改變附著在波導(dǎo)壁上金屬貼片的尺寸和周期,在安裝后靈活調(diào)整漏泄圓波導(dǎo)不同地方的耦合損耗,從而克服了漏泄圓波導(dǎo)耦合損耗因結(jié)構(gòu)固定而無法改變的局限性。 4.以雪覆蓋為例,研究了外界環(huán)境對漏泄波導(dǎo)輻射特性的影響,提出了一種在漏泄波導(dǎo)周圍覆蓋一層泡沫塑料層以降低環(huán)境影響的方法。研究表明,該方法可以有效降低積雪對波導(dǎo)輻射特性的影響。此外,針對僅工作在漏泄波導(dǎo)近距離處的通信系統(tǒng),提出了通過在波導(dǎo)表面添加介質(zhì)層來增強漏泄波導(dǎo)近距離處場強的方法,使漏泄波導(dǎo)的輻射能量能夠聚焦到所需要的方向。 5.基于基片集成波導(dǎo)提出了一種N型縫隙圓極化漏波天線,并進行了加工測試。計算和實驗結(jié)果表明,通過選擇合適的縫隙結(jié)構(gòu)和基片集成波導(dǎo)的基板參數(shù),該N型縫隙漏波天線能夠在8GHz頻段和5.8GHz ISM頻段實現(xiàn)圓極化輻射。
[Abstract]:Leaky waveguides and leaky antennas have been widely used in wireless communication systems. In recent years, with the increasing demand for wireless communication and the development of automatic train control system based on wireless communication, the problem of efficient radio coverage in restricted space has been paid more attention. Therefore, leakage waveguides and leaky antennas, which are the main means of radio coverage in confined space, have become the focus of research. The purpose of this paper is to study a new type of leaky waveguide and leaky antenna which is suitable for the confined space with high efficiency radio wave coverage. The radiation characteristics of the new leaky waveguide are analyzed, the structure design and the environmental adaptability of the application are studied. At the same time, the circular polarization leaky wave antenna suitable for confined space is studied on the basis of leaky waveguide. The research work is of great significance to improve the radio coverage performance in restricted space and improve the reliability of wireless communication. The main work and innovative results of this paper are as follows: 1. A leakage circular waveguide structure is designed to replace leakage coaxial cable in high frequency band and reduce the transmission loss of the system. Based on the theory of leakage coaxial cable, the radiation mode and far-field characteristics of leaky circular waveguide are analyzed, and the relationship between coupling loss and structural parameters is given. The results show that there is not only the space harmonic radiation of m 0 order, but also the space harmonic radiation of m 鈮，

本文編號：2191536