保真度论文：超宽带高保真天线的研究与设计

1、保真度论文：超宽带高保真天线的研究与设计【中文摘要】在超宽带通信系统设计中，需要综合考虑脉冲波形 的产生和发射/接收天线对脉冲波形传输质量的影响。在非超宽带天 线的设计中，一般采用驻波比、增益、方向图等参数来衡量天线性能 的好坏。这些参数都是频率的函数，它们在一定的带宽范围内变化不 大。但是,当天线的带宽是几倍的频程甚至十几倍频程，即对于超宽带 天线,上述电参数已不足以反映超宽带天线的性能。因此,超宽带天线时域脉冲波形的保真度逐渐成为超宽带天线性能的研究热点。本文在研究保真度与天线参数关系的基础上，设计了一款保真度较高的超宽 带天线。论文分为四个部分。首先介绍了发展超宽带天线的意义，然后讨论了

2、脉冲信号经过超宽带天线及自由空间时产生失真的过程及 原因，给出了本文的研究方法。其次，介绍了超宽带天线的性能参数，并给出了超宽带天线系统框图及其传输信号的计算与测量方法。然后基于 Half-PTMA 超宽带天线的时频域特性分析，研究了超宽带天线的 相位-频率特性、增益-频率特性与脉冲信号保真度之间的关系。然后, 在分析Vivaldi 天线结构参数与性能关系的基础上，设计并制作了一 款阻抗带宽为 3GHZ-11GHZ 勺超宽带反对称 Vivaldi 天线，研究了该超 宽带天线相频特性、增益-频率特性与脉冲信号保真度之间的联系。 综合上述两种天线，得到了超宽带天线的保真度与增益-频率特性、相 频特

3、性的联系，为高保真超宽带天线的设计提供了理论依据。最后，设计了一款保真度较高的超宽带半平面单极天线。 论文首先分析了单极子天线的参考模型一一梯形平面单极子天线的各个结构参数的作用,然后应用加载及阻抗匹配技术设计出一款阻抗带宽为650MHZ-11.5GHZ勺超宽带平面单极天线，仿真得到该天线的发射或接 收的保真度为 0.86,测量得到该天线的发射和接收的保真度为0.78。将上述超宽带平面单极天线对半切，得到了一款超宽带半平面单极天 线,仿真得到该天线发射或接收脉冲信号的保真度为0.98,测量得到该天线发射和接收脉冲信号的保真度为0.85。【英文摘要】In the desig n of ultra

4、-wideba ndcom muni cati onsystems, the impact on transmitting signals quality by theproduc ing of pulse waveforms and laun ch/recei ving antennas should becon sidered comprehe nsively. Gen erally, sta nding wave ratio, gai n anddirecti onal patter n are used to measure antenna s performanee innarrow

5、-band antennas design, which are functions of frequency, andhave micron-variation in a certa in range of ban dwidth. However, whe nthe ban dwidth is several octaves or a doze n octaves, e.g. ultra-wideband antenn as, the electrical characteristics men ti oned above are not enough to reflect ultra-wi

6、deba nd antennas performa nee.Consequently, the fidelity of ultra-wideband antennas pulsewaveform in time-doma in gradually becomesresearch hotspot in theresearch of ultra-wideband antennas performanee. Based on the studyof relati on ship betwee n fidelity and antennaparameters, a high-fidelity ultr

7、a-wideband antenna is desig ned.Thisthesis is divided into four parts. Firstly, the significanee of developingultra-wideband antennas is in trodueed. And the n, the cause and processof distorti on produced whe n pulse sig nals travels through ultra-wideband antennas and free space are expla in ed. A

8、nd the n, the researchmethod for this paper s subject is give n. Sec on dly,this paperin troduces the performa nee parameters of ultra-wideba nd antennas,and gives the ultra-wideband antenna system diagram and the calculation and measureme nt methods for the tran smitt ing sig nals. Then, basedon th

9、e freque ncy- and time-doma in an alysis of ultra-wideba ndhalf-PTMA antenna, relatio nship betwee n phase-freque ncyCharacteristics、gain-frequency characteristic of ultra-wideband antennas and fidelity ofpulse sig nals is researched.The n, on the an alysis of relati on shipbetwee n the structural parameters and the property of Vivaldi antenna, aultra-wideba nd an tipodal Vivaldi antenna is desig ned and fabricated withimpeda nee ban dwidth of 3GHz-11GH z. And then, relatio nship betweenfidelity of pu