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硕士论文-时域天线及其阵列研究，正文共79页。
【摘要】 超宽带技术在民用、军用和微波武器等方面有广泛的应用前景。天线是这些系统的一个重要组成部分,它的功能是接收和辐射无线电波。用于脉冲信号辐射的天线在信号传输中有别于传统的宽带天线和窄带天线。天线辐射脉冲信号的保真度和效率直接影响着系统的性能。本文主要围绕时域天线单元和阵列天线设计,对设计天线的频域和时域特性进行讨论。在阵列天线设计中,改变阵列天线之间的距离,得出阵列天线设计中的结论。本论文包括如下内容：第一章介绍了超宽技术的研究背景、意义和国内外研究进展；归纳了超宽带天线的类型,并分析了这些天线的时域特性,从时域特性中得出适合脉冲辐射的天线；对本文所涉及的蝴蝶结天线和Vivaldi天线进行了重点介绍。最后对超宽带的关键技术和时域天线的发展趋势进行了展望。第二章介绍了时域天线重要参数,从瞬态脉冲信号的时域和频域特性分析得出,用于脉冲辐射的天线必须具有超宽带特性；本章对时域天线辐射和传输原理进行分析,并对时域天线辐射波形的畸变和振铃现象原因进行了解释；最后对超宽带雷达方程和窄带雷达方程进行了比较。第三章根据“XXX”项目需要设计了椭圆蝴蝶结天线；从辐射脉冲信号出发,说明降低天线的低端工作频率的重要性,并在文章中比较了两种脉宽相同信号的辐射特性,将两个不同信号的保真度进行了比较；根据要求天线尺寸小于70mm,通过加金属环降低天线的低端工作频率,设计出的天线能够工作在1.3GHz-7.8GHz,；由于设计天线馈电的SMA的阻抗为50Ω,天线辐射部分输入阻抗为100Ω,设计了馈电巴伦达到阻抗匹配,巴伦的尺寸为8mm×17mm；最后对天线的频域和时域特性进行了分析,通过峰值方向图说明天线具有良好的辐射特性；设计的天线经过实物加工,并通过矢网E507IC测试,仿真结果和测量结果相同。第四章设计了用于大功率辐射的Vivaldi天线；Vivaldi天线的时域和频域特性都满足设计的需要,天线在低端工作频率为0.32GHz,通过峰值方向图说明天线具有很好的定向辐射特性；在单元天线设计的基础上,对天线进行阵列设计；阵列天线在远场都得到很好的合成,合成波形的脉冲宽度和单元天线的脉冲宽度均为1.7ns。通过改变天线之间的距离,得出改变阵列天线不同方向的距离对阵列天线的影响不同,并给出相应的结论；最后对设计的阵列天线进行了波束扫描仿真,仿真结果和理论计算一致。第五章对文章的工作和创新点进行了总结,对超宽带技术以后的发展提出了自己的看法。
【Abstract】 Ultra-wideband technology has great perspective in the application of the civil, military and microwave weapons, and the antenna which is as an important part of this system has functions of receiving and radiating radio wave. The antenna applied in the impulse signal radio is different from the traditional broad band antenna and narrow band antenna in signal transmitting process. The fidelity and effect of antenna’s radiate impulse signal directly influence the performance of the system.This thesis focuses on the designing of pulse antenna elements and array antenna. The characteristics of frequency domain and time domain are discussed. Some useful conclusions would derived by changing the distances between the neighbors. The contents of this paper are as follows:The first chapter of this paper introduces ultra-wide band antenna technology in the aspects of the background, significance and progress at home and abroad. Several types of UWB antennas are summarized and their time-domain characteristics are analyzed. The antenna applied for pulse radiation is deduced by characteristics of the time domain. This article highlights the development of the bowtie antenna the Vivaldi antenna. Finally, key UWB technologies and development trends of time-domain antenna are discussed.The second chapter introduces several parameters of the time-domain antenna. From the time domain and frequency domain characteristics of UWB pulse antenna, it can be concluded that pulse antenna must be of wideband character. This chapter also analyzes the radiation and transmission principles of pulse antenna, and discussed the causes that lead to its waveform distortion and ringing phenomenon. Finally, comparison between narrow-band radar equation and ultra-wideband radar equation were demonstrated.Elliptical bowtie antenna is designed according to requirement of "XXX" project, and the radiation pulse is introduced to explain the importance of reducing the lower operating frequency. The radiation characters of two same signals with different pulse-widths are compared. According to design requirements, the antenna with size less than 70mm shall be able to operate at frequency from 1.32 to 7.81 GHz, and the antenna with metal ring can reduce the frequency at the lower end. Since the input impedance of SMA is 50Ω, and input impedance of Antenna is 100Ω, a balun with size of 8mm×17mm was designed for impedance matching. Finally, its characteristics of frequency domain and time domain are analyzed. According to the derived peak pulse radiation pattern, the antenna has excellent radiation characteristics. The antenna is manufactured and tested by vector analyzer E5071C. The simulation results and measurement results agree well with each other.In the fourth chapter, Vivaldi antenna used for high-power radiation is designed. Its time domain and frequency domain characteristics of meets the design needs while the lower operating frequency of the antenna is 0.32GHz. The peak pattern indicates the antenna has good directional radiation character. The antenna array is designed based on the design of Vivaldi antenna. Far field of the Array are synthesized and the pulse is 1.7ns. By changing the distance between antenna elements, it can conclude that the effects by changing distances at different directions are different. Finally, the beam scanning simulation is employed on array antenna and the simulation results and theoretical calculations are consistent.The work and innovation of the article are summarized in Chapter V and presented my views on further development of UWB technology.
【关键词】 超宽带天线； 蝴蝶结天线； Vivaldi天线； 时域天线；
【Key words】 ultra-wideband antenna； bowtie antenna； Vivaldi antenna； time-domain antenna；