【作者】 潘咏梅；

【导师】 徐善驾；

【作者基本信息】 中国科学技术大学 ， 电磁场与微波技术， 2009， 博士

【摘要】 根据电磁工程发展的实际需要,本论文提出多种新型的导波和漏波天线结构,并采用以场和路相结合为基本特征的电磁场工程化方法对它们的传输和辐射特性进行了深入系统的研究。这些方法主要包括广义散射矩阵技术、通用模匹配法、复功率守恒法、横向谐振技术、改进微扰法、有源传输线等效电路法等。研究表明:该类分析方法具有准确、有效、灵活方便的特点,从而能取得事半功倍的效果;所提出的新型微波毫米波结构,包括周期矩形栅漏波天线,无辐射介质(NRD)波导和槽波导结构,以及等效介电常数接近零(ENZ)的矩形波导和圆波导,具有一系列独特的电磁特性,例如倒置矩形栅介质漏波天线辐射较传统的介质栅天线明显增大,左手介质(LHM)衬底的金属栅天线可同时支持前后向两个辐射波束,ENZ介质窄波导可实现能量“超耦合”,展示了它们在微波、毫米波工程中诱人的应用前景,可以用来设计和研制高效率小尺寸的漏波天线、双波束辐射扫描天线以及新型强场仪和新型媒质介电常数测量系统等。最后论文对左手介质波导中普遍存在的复数模问题进行重点讨论,指出复数模是该类型波导完备本征模的组成部分,在进行相关数值计算时必须特别注意这一点以确保计算结果的准确性,这对左手介质导波结构传输特性的研究具有重要的理论指导意义。更多还原

【Abstract】 In line with practical needs of development in electromagnetic engineering,in this thesis,we propose various new dielectric waveguiding and leaky-wave antenna structures,the propagation and radiation properties are systematically investigated through engineerized electromagnetic approach characterized by combining the ’field method’ with ’circuit method’,which mainly involves generalized scattering matrix method,mode-matching method,conservation of complex power technique, transverse resonance technique,improved perturbation method,active transmission line method,and etc.The investigation reveals that these methods are effective, accurate,and flexible,thus can get twice the result with half the effort;the new proposed microwave and millimeter-wave structures including rectangular periodic leaky-wave antennas,modified NRD and groove guide structures,as well as the equivalent ENZ rectangular and circular channel waveguides,exhibit unique electromagnetic phenomena.For example,the radiation of inverted rectangular dielectric grating antenna enhances greatly compared with the traditional grating structure,the metallic grating antenna with LHM substrate supports simultaneously two radiation beams,and ultra-narrow ENZ channel possesses supercouplering ability, which illuminate that they are of promising applications in microwave and millimeter-wave engineering.For instance,they can be used to develop and design small size leaky-wave antenna with high efficiency,double-beam radiation antenna, intense field cavity and measuring system for dielectric constant of material.Lastly, the issue of complex mode which exists in the LHM waveguide structures everywhere is carefully discussed.We indicate that complex mode is the constituent part of complete eigen mode set in the LHM structures,and great attention should be paid to its effect when carrying on correlative calculations to guarantee the accuracy of the numerical results,this is of theoretically significant for the investigation on propagation characteristics of LHM waveguides.更多还原