非对称单脊波导裂缝阵天线分析

将Ｅｌｌｉｏｔｔ关于矩形波导缝阵理论推广运用到非对称单脊波导裂缝天线上，在考虑了裂缝外部互耦影响的情况下，给出相应的两个设计方程，同时给出８单元谐振裂缝阵的具体计算和设计方法。加工样品的近场和远场测试结果证明了本文理论和设计方法是正确有效的。     

非对称单脊波导裂缝阵天线分析

将Elliott关于矩形波导裂缝阵理论推广运用到非对称单脊波导裂缝阵天线上,在考虑了裂缝外部互耦影响的情况下,给出相应的两个设计方程,同时给出8单元谐振裂缝线阵的具体计算和设计方法。加工样品的近场和远场测试结果证明了本文理论和设计方法是正确有效的。     

由盒式带线馈电的共线纵向裂缝阵的设计

本文介绍一种解析设计方法,它能在存在外部互耦的条件下,对给定的口径分布和输入阻抗,确定一个共线裂缝阵中每个缝的长度和带线相对于每个缝的倾角。这种理论是建立盒式带线的TEM模电流与裂缝电压间关系的Stevenson近似法的推广,同时应用几何绕射理论(GTD)来表示裂缝单元之间的外部耦合。于是引入了一种将谐振缝长度限制在实际值的最新方法。为证实该理论而设计的一个阵给出了良好的结果。     

平板裂缝天线子阵形变后的方向图分析

子阵方向图对平板裂缝天线的工作性能有着重要的影响。本文给出了常用的子阵设计方法,并针对可能出现的形变,提出了从单元位移和幅相的变化来分析子阵形变后的方向图的方法,分析结果表明:位移主要对主瓣宽度的影响较大,而幅相的变化主要对副瓣的影响较大。文中讨论、分析了子阵在不同形变情况下的方向图主瓣宽度、副瓣电平等性能,并给出了相应的理论结果和仿真结果。     

矩形波导窄边裂缝驻波阵列天线的设计

对于波导窄边裂缝小阵列天线，在孤立裂缝导纳特性已知情况下，采用阵中有源导纳概念，结合场的方法和路的方法，通过计算裂缝的内，外部互耦，对孤立裂缝导纳进行修正，经简单的计算迭代即可获得满足误差要求的诸裂缝设计参数，实践证明，在天线副瓣电平ＳＬＬ要求不太高的情况下，在孤立单缝特性实验的基础上，就可获得设计上的一次成功，本文给出了设计实例，在设计频率上实测的ＳＬＬ与理论值（－３０ｄＢ）仅相差１ｄＢ在５％的     

等长双裂缝波导耦合机构研究

对一种新的裂缝阵馈电机的良好性能进行分析，同时强调了设计该类型蚀是民机构时所要注意的一些因素，给出了测试曲线。     

用于扫描平面阵的非对称脊波导辐射单元

本文论述了方位电扫的大型低副瓣平面裂缝阵所采用的一种新颖的线阵辐射单元。平面阵由若干直立的谐振线阵单元,即有宽壁并联裂缝的单脊波导构成,裂缝间距很近,以免阵列在方位扫描时产生阵列栅瓣。传统的线性宽壁裂缝阵要求裂缝交替地开在离波导中线的两边,然而在电扫描期间会在偏移方向上产生不需要的二次波束。为消除二次波束。提出了一种把所有裂缝都精确直排在波导中心线上的设计方法。文中论述了实现波导非对称性要求的各种方法,同时给出了成功方法所采取的设计步骤及由验证模型取得的实验结果。     

平板裂缝天线子阵激励装置设计及带宽分析

子阵激励装置的带宽特性对平板裂缝天线的波瓣带宽和驻波带宽有着重要影响,本文针对目前国内外常用的各种阵激励形成的带宽特性作了一些分析,并给出了其中几种阵激励形成的设计计算,文中主要讨论,分析了几种子阵激励装置的相位带宽和驻波带宽,并给出了相应的仿真结果和实验验证结果,为工程应用提供了设计参考。     

毫米波段斜扇形波束裂缝阵天线的研究

研究的毫米波段斜扇形波束裂缝阵天线是一种薄形的波导裂缝阵,结构新颖,特别适用于飞行器天线。由于这种天线的数学模型比较复杂,并且工作在毫米波波段,使设计和分析带来了一定的困难。根据裂缝阵设计的理论基础,对毫米波段斜扇形波束裂缝阵天线进行了研究,采用了终端短路的准行波天线阵的方案,设计得到的毫米波裂缝阵天线具有斜角扇形波束,较低副瓣,宽频带和薄形等优点。理论结果和实测结果相吻合,在工程上应用已得到了良     

不规则子阵固态有源阵多阶振幅量化

对不规则子阵固态有源相控阵多阶振幅量化进行理论研究,给出其设计原理与途径。研究结果表明,利用较少量化台阶数,多阶振幅量化阵可实现较低的副瓣电平。尤其对于发射阵而言,该方法有利于减少组件品种和设计成本,适于工程应用。文中给出设计实例,验证了不规则子阵多阶振幅量化的正确性。     

适于一维相控阵宽角扫描的非对称单脊波导裂缝线源

非对称单脊波导裂缝线源是一种新型相控阵天线辐射单元。由该种单元垂直放置构成的平面相控阵天线在水平面可实现宽角(60)扫描,在波束扫描时,还可以避免寄生副瓣的出现。同时,该种单元本身在垂直面易于实现较低的副瓣电平。本文从理论和实验上对非对称单脊波导裂缝阵天线进行了研究,解决了该种线源设计过程中的基本理论和关键技术。十六单元样品线源远场实验结果与理论值的一致性说明了本文的理论分析和实现途径是正确有效的。     

Analytic design of conformal slot arrays

A completely analytic design process has been developed for small slot arrays which accounts for the varying effect of mutual coupling as a function of element position. A previously developed theory for the design of small arrays has been extended to include conformal dielectric-filled waveguide slot arrays. Computer software has been assembled which enables calculation of the slot geometries required to implement a specified aperture distribution and input impedance condition. The slot self- and mutual admittances are calculated numerically, thus eliminating the traditional measured slot data from the design process. This design technique has been applied to conformalX-band slot arrays on cylinders of a few wavelengths diameter. The arrays consist of multiple dielectric-filled waveguides, each of which is a narrow-band standing-wave linear array of longitudinal shunt slots. The computerized design process adjusts the length and offset of each slot in the total array until the desired aperture distribution and impedance match are achieved. A flow diagram of the design program and test results from experimental arrays are presented.     

The design of small slot arrays

The differences in mutual coupling for a central slot and a peripheral slot cannot be ignored in small arrays if good patterns and impedance are to be obtained. A theory has been developed whereby the length and offset of every slot in the array can be determined, in the presence of mutual coupling, for a specified aperture distribution and impedance match. The theory enlarges on Stevenson's method, and uses a modified form of Booker's relation based on Babinet's principle to treat nonresonant longitudinal shunt slots in the broad wall of a rectangular waveguide. A general relation between slot voltage and mode voltage is developed, and then formulas are derived for the active, self-, and mutual admittances among slots. These formulas result in a design procedure. Analogous treatments of inclined series slots in rectangular guide and of strip-line-fed slots are possible. Comparison between various experiments and the theory is presented. Tests of the theory include the resonant length of a zero offset slot, resonant conductance versus offset and resonant conductance versus frequency for a single slot, and self- and mutual admittances for two staggered slots. The design and performance of a two-by-four longitudinal shunt slot array is also described.     

Broadband printed ring-slot array with circular polarisation

A novel design of a printed ring-slot antenna with circular polarisation (CP) is first proposed. The CP radiation of the slot antenna is achieved by a series microstrip-line feed configuration. Using the single CP slot antenna as an array element, the 1times2 and 2times2 slot arrays are constructed and measured. To obtain wider CP bandwidth, phase sequential rotation technique is applied to the feed network of these printed slot arrays. The experimental results show that the 2times2 slot array antenna is capable of 15% bandwidth for an axial ratio of less than 3 dB     

Scan-independent slot arrays with parasitic wire arrays in astratified medium

The effect of a parasitic wire array on the scan admittance of a slot array has been investigated. Structures considered can consist of an infinite slot array and an arbitrary number of parasitic infinite arrays of piecewise linear wires, all arrays being embedded in a stratified medium. These include, as particular cases, phased arrays of Clavin elements. Expressing the fields from the arrays as plane waves, a procedure similar to the periodic moment method for infinite periodic structures is set up to obtain the scan admittance of the slot array. Scan admittances are presented for a slot array with monopole arrays in free space, and a slot array with a tilted dipole array in a stratified medium. Blind spots at which the incident energy is mainly reflected rather than transmitted were found. Results obtained indicate the possibility of using parasitic wire arrays for scan compensation of active slot arrays     

The design of transverse slot arrays fed by the meandering strip of a boxed stripline

Transverse slots fed by a boxed stripline, with the strip passing centrally under the slot at an angle which controls the coupling, have been investigated theoretically and experimentally. A procedure has been developed which permits the design of arrays of such slots, including the effects of external mutual coupling. Agreement between theory and experiment has been found to be good for both a single slot and a linear array.     

Efficiency and gain of slot antennas and arrays on thick dielectric substrates for millimeter-wave applications: a unified approach

A unified approach for representing the surface-wave fields and for computing the corresponding radiation efficiencies from arbitrarily shaped slot-type antennas on thick dielectric substrates at millimeter-wave (mm-wave) frequencies is presented. In this approach, two different representations of the surface-wave fields, i.e., the one based on the idea that the surface-wave power can be associated with a substrate radiation pattern and the other based on the cylindrical wave expansion, are linked together in a unified way. The developed theory is then applied for investigating the surface wave characteristics of printed twin offset slots and uniform linear slot arrays. Based on the developed theory, new insight into the mechanism with which surface-wave power is coupled by the slot pair is presented. Subsequently, the optimum number of elements and corresponding interelement spacing for linear, uniformly excited, slot dipole arrays is explored for achieving maximum radiation efficiency and gain. In order to provide guidance on practical mm-wave integrated slot antenna array design, supportive numerical results are presented for Substrates of dielectric constant /spl epsi//sub r/ = 4.0 and /spl epsi//sub r/ = 12.0.     

耦合纵缝馈电的短路波导宽边纵缝阵的分析与设计

基于三层结构（馈电缝、耦合缝、辐射缝）平面缝隙阵天线设计的需要,用场分析法对由耦合纵缝馈电的两端短路波导宽边直线纵缝阵进行了分析和综合。该法考虑了所有的互耦、高次模及波导壁厚的影响,得到了耦合纵缝馈电的两端短路波民宽边纵缝直线阵在辐射缝偏心距相同和缝长相同时直线缝阵口径分布等幅同相的结论。利用所得结论并结合泰勒线阵综合法提出了适合于对文中系统进行综合的有效方法。