Multilayer Substrate Integrated Waveguide Six-Port Circuit

In this paper a new design of a six-port circuit based on multilayer substrate integrated waveguides (SIW) is presented. This design is based on the use of a multilayer structure aimed at reducing the dimension of the circuit while conserving the performances of the component. The designed SIW six-port is composed of two basic elements, a SIW power divider and directional coupler. These two elements are designed, optimized and matched to produce a better performance at the required operating frequency of 11 GHz. The results of simulations show that the new multilayer SIW six-port circuit has good performances including a good return loss and isolation under–20 dB and the transmission magnitude better than–10 dB. This multilayer SIW six-port has the advantage of a small size 160-34.8 mm; its width is about 50% smaller than the planar SIW six-port circuit, which helps to get a higher density of integration in telecommunication systems and allows much smaller devices to be conceived.A microstrip toSIWtransition is used in order to facilitate the integration of this component into other planar circuits. The structures are designed, simulated and optimized using the Ansoft HFSS simulation software.     

毫米波双通带基片集成波导滤波器设计

提出了一种新型毫米波双通带基片集成波导(SIW)滤波器,该滤波器由双模基片集成波导和双模带线谐振器构成。其中双模带线谐振器嵌入到双模基片集成波导谐振腔中,不占据额外的电路面积,利用双模带线谐振器的TEM模和双模基片集成波导谐振腔的两个简并模式TE102、TE201,可分别形成两个相互独立的通带,因此该滤波器的设计具有很大的灵活性。所设计的双通带滤波器具有三个传输零点,实现了良好的带外抑制和带间隔离度。该双通带滤波器工作于28.4GHz和32.2GHz,3dB带宽分别为2%和3%。最终的测试结果和仿真结果相吻合,证明了该设计方法的可靠性。     

Millimeter Wave Substrate Integrated Waveguide Antennas: Design and Fabrication Analysis

The paper presents a new concept in antenna design, whereby a photo-imageable thick-film process is used to integrate a waveguide antenna within a multilayer structure. This has yielded a very compact, high performance antenna working at high millimeter-wave (mm-wave) frequencies, with a high degree of repeatability and reliability in antenna construction. Theoretical and experimental results for 70 GHz mm-wave integrated antennas, fabricated using the new technique, are presented. The antennas were formed from miniature slotted waveguide arrays using up to 18 layers of photo-imageable material. To enhance the electrical performance a novel folded waveguide array was also investigated. The fabrication process is analyzed in detail and the critical issues involved in the fabrication cycle are discussed. The losses in the substrate integrated waveguide have been calculated. The performance of the new integrated antenna is compared to conventional metallic, air-filled waveguide antennas, and also to conventional microstrip antenna arrays operating at the same frequencies.      

半模基片集成波导馈电的对数周期偶极子天线

设计并研制了一种基于半模基片集成波导(Half-mode Substrate Integrated Waveguide:HMSIW)馈电的单层宽带印刷对数周期偶极子阵列(Printed Log-Periodic Dipole Array:PLPDA)天线.对数周期偶极子阵列(PLPDA)天线具有频带宽、剖面低、重量轻等优点,但是其馈电需要平衡线结构.半模基片集成波导具有平面集成、主模带宽宽、损耗低、尺寸小等优点,同时自身天然具有平衡结构.文中设计并制作了工作频率为15GHz～40GHz的HMSIWPLPDA天线,测试结果和仿真结果吻合.     

一种新型的基于半模基片集成波导技术的Butler矩阵

提出并实现了一种新型的基于半模基片集成波导技术的Buffer矩阵,实际制作的样品工作在X波段(10GHz),实测插入损耗为2dB,样品尺寸为24cmx6.5cm.采用了标准的双面PCB工艺,该结构与传统的微带电路相比具有插入损耗低、功率容量大等特点,与基片集成波导相比具有面积小的优点,是一种适合于在微波毫米波频段多波束天线使用的波束形成网络.文中给出了具体设计过程和测试结果.     

Periodic Leaky-Wave Antenna for Millimeter Wave Applications Based on Substrate Integrated Waveguide

Substrate integrated waveguides (SIW) are built up of periodically arranged metallic via-holes or via-slots. The leakage loss of SIW structures increases with the distance between the via-holes or via-slots. An open periodic waveguide with a large via distance supports the propagation of leaky-wave modes and can thus be used for the design of a leaky-wave antenna. In this paper, this leakage loss is studied in detail and used to design a periodic leaky-wave antenna. The proposed concept represents an excellent choice for applications in the millimeter-wave band. Due to its versatility, the finite difference frequency domain method for periodic guided-wave or leaky-wave structures is used to analyze the characteristics of the proposed periodic leaky-wave antenna. Two modes (${rm TE}_{10}$ and ${rm TE}_{20}$) are investigated and their different leaky-wave properties are analyzed. Based on the proposed leaky-mode analysis method, a novel periodic leaky-wave antenna at 28–34 GHz is designed and fabricated.      

基于半模基片集成波导的双频段缝隙天线

基于半模基片集成波导技术,提出了一种适用于微波集成电路的双频段缝隙天线。该双频段天线由馈电微带线,一段半共面波导结构和具有辐射缝隙的半模基片集成波导谐振腔构成,利用半模基片集成波导谐振腔的多模式工作特性实现了天线多频段特性。仿真和测试结果表明,该天线能同时工作在C频段(谐振频率5.74 GHz,S11=-21.86 dB)和X频段(谐振频率11.33 GHz,S11=-25.09 dB),不需要同时采用两个天线,具有便于和平面电路集成、体积小、结构简单、成本低等优点。     

Characterization of the Propagation Properties of the Half-Mode Substrate Integrated Waveguide

The propagation properties of the half-mode substrate integrated waveguide (HMSIW) are studied theoretically and experimentally in this paper. Two equivalent models of the HMSIW are introduced. With the first model, equations are derived to approximate the field distribution inside and outside the HMSIW. Using the second model, an approximate closed-form expression is deduced for calculating the equivalent width of an HMSIW that takes into account the effect of the fringing fields. The obtained design formulas are validated by simulations and experiments. Furthermore, the attenuation characteristics of the HMSIW are studied using the multiline method in the frequency range of 20–60 GHz. A numerical investigation is carried out to distinguish between the contributions of the conductive, dielectric, and radiation losses. As a validation, the measured attenuation constant of a fabricated HMSIW prototype is presented and compared with that of a microstrip (MS) line and a substrate integrated waveguide (SIW). The SIW is designed with the same cutoff frequency and fabricated on the same substrate as the HMSIW. The experimental results show that the HMSIW can be less lossy than the MS line and the SIW at frequencies above 40 GHz.      

基于树状分形结构的半模基片集成波导带通滤波器

提出了一种基于分形结构的半模基片集成波导(HMSIW)滤波器。该设计将树状分形结构蚀刻在HMSIW的上金属表面,通过在其高频端引入宽阻带来产生带通效应。这种基于树状分形的HMSIW带通滤波器结构,随着迭代次数的增加,其相对带宽基本保持不变(S11<-15dB),但其带通边缘频响斜度变陡,且带外抑制特性不断增强。仿真结果与实验结果基本吻合,较好地验证了设计的可行性和有效性。     

毫米波基片集成均衡器设计与实现

利用基片集成波导设计微波器件时,首先需要解决与矩形波导的等效宽度转换问题,现有等效宽度计算方法精度较低、使用范围有限,文中与仿真软件相结合,提出了一种新的基片集成波导等效宽度计算方法,该方法计算准确、实现简单。利用该方法进行分析,设计了一种毫米波基片集成均衡器,与腔体式均衡器相比,其解决了小型化的问题,尺寸和重量可以减小90%以上;与微带式均衡器相比,其损耗小、Q值高且克服了微带均衡器小型化后无法二次调节的问题。     

毫米波波导成型技术

用活动模芯代替钢带是毫米波波导弯曲成型的有效方法,该工艺的关键是模芯的设计与制造。采用活动模芯弯曲毫米波波导,重点讨论了模芯尺寸、模芯形状和回跳角对波导尺寸和表面粗糙度的影响,并对该工艺制备的样品进行了测定。结果表明:当模芯尺寸与波导内腔实际尺寸差值在0~0.02 mm,不同的弯曲半径和弯曲角度给予不同的回跳角预设值,可以制造出满足设计要求的弯波导。     

一种基于印刷工艺的新型毫米波波导缝隙天线

针对传统的波导缝隙天线和微带贴片天线在毫米波段所存在的缺点,本文提出利用印刷工艺来制造毫米波波导缝隙天线。与以往的结构相比,新结构不仅可以提供满足毫米波段应用的精度和较低的成本,而且可以在一定程度上抑制旁电平。基于这种结构,本文设计并制作了Ｋａ波段的两种波导缝隙天线。实验结果和设计结果吻合,证明该结构的可行性和有效性。     

A Multilayer Waveguide Window for Wide-Bandwidth Millimeter Wave Tubes

A multilayer waveguide window is demonstrated to exhibit wide bandwidth and high transmission for applications in high-frequency microwave tubes. A transfer matrix approach is employed to discretize the dielectric function profile of the multilayer heterostructure in a rectangular waveguide. The closed form has been obtained and the corresponding reflection and transmission characteristics have been carried out. The analytical calculation is also compared with the result of numerical simulation via the finite-element code HFSS. The exact calculation agrees with the numerical simulation very well. By comparison, the approach not only enhances the accuracy and efficiency, but also gives a good criterion for the design. The results show that the bandwidth for a transmission of 99%, i.e., S ₁₁ below –20 dB, can be optimized to be about 8.75 GHz at a central frequency of 35 GHz or about 25%. A wide-bandwidth waveguide window can be easily designed for Ka-band and W-band tubes, and even for higher frequency ones.     

一种新型半模基片集成波导三孔定向耦合器

半模基片集成波导(HMSIW)是近年来出现的一种高性能平面导波结构,具有传输损耗小、功率容量大、易于集成等优点,已开始广泛应用于微波无源器件的设计中。文章基于HMSIW技术与PCB工艺技术设计制作了一种新颖的三孔定向耦合器,通过在耦合孔上金属面蚀刻"工"字形槽增加孔的耦合量。设计的HMSIW三孔定向耦合器不仅保持了集成基片波导(SIW)定向耦合器的所有优点,而且在面积上减小了近50﹪,工作带宽拓展到1GHz。实测数据与仿真结果基本吻合,验证了设计方法的正确性与可行性。     

单层平面基片集成波导双通带滤波器的仿真研究

提出了一种基于单层基片集成波导谐振腔的双通带滤波器。滤波器由传统折叠排列的6个谐振腔组成。通过在通带内设置一对传输零点,将传统滤波器的通带一分为二,实现了双通带。仿真结果表明滤波器的两个通带分别工作于9.85 GHz和10.08 GHz,在相对带宽分别为1.29%和1.76%的通带内,插入损耗小于1.68 dB和1.3 dB,回波损耗大于24 dB和14 dB,通带之间的隔离大于17 dB。该滤波器在无线通讯系统中具有良好的应用前景。     

一种基于LTCC 技术的脊基片集成波导（SIW）到微带的过渡结构

介绍了一种基于LTCC 技术的脊基片集成波导（SIW）到微带的过渡结构。将传统脊波导到微带过渡的设计思路,运用于基于LTCC 技术的基片集成波导（SIW）到Rogers5880 基片微带的过渡设计中,实现了LTCC SIW 到Rogers5880 基片微带的宽带过渡。从仿真结果可以看出,在25.2GHz 到40GHz 的频带内,回波损耗S11 小于-15dB, 插入损耗优于-0.2dB。     

A Dual Six-Port Network Analyzer Using Diode Detectors

The performance of a dual six-port network analyzer using diode detectors is described. The network analyzer operates over the 2-18-GHz band using commercially available low-barrier Schottky diodes. The paper describes the process for calibrating the diodes for deviation from square law. Measurement results are presented showing the accuracy and precision of tbe six-port network analyzer when measuring 1-port and 2-port devices. Key work attenuation measurements, automated network analyzer, impedance measurements, microwave network analyzer, network analyzer, and six-port.     

A Fast Finite Element Analysis of Millimeter Wave Waveguide Filters

The multifrontal method is applied for solving a large system of linear equations resulting from the use of edge-based finite element method (FEM). The finite element method combined with the perfectly matched layers (PML) is given for simulation of microwave filters and the algorithm of multifrontal method is described in detail. The reflection and insertion losses of millimeter wave filter are analyzed as the examples and the obtained results are compared with those obtained from literature. In order to demonstrate the efficiency of the multifrontal method, the computational time is compared with that of both symmetric successive overrelaxation (SSOR) preconditioned conjugate gradient (PCG) and conjugate gradient methods (CG) for the thick-iris waveguide bandpass filer.     

X-Band Substrate Integrated Waveguide Amplifier

Design and realization of a compact X-band single-transistor amplifier with substrate integrated waveguide (SIW)-based input and output matching networks is presented. The overall size of the proposed SIW amplifier is only $1.5lambda_{rm g}$ at the center frequency. Using a calibration technique, we extract the $S$ -parameters of the fabricated amplifier with reference to its SIW ports. Measurements show that the amplifier features 10 dB of power gain with less than 2 dB of ripple and more than 10 dB of input and output return losses on the SIW ports in the entire frequency band. Due to an appropriate modeling of the constituent blocks of the amplifier, a good agreement between the simulation and measurement results is observed.      

一种新型基片集成波导合成器的设计

设计出了一种Ka频段9路基片集成波导合成器,通过HFSS软件仿真,频带内插入损耗达到0.6dB,反射达到-20dB,驻波比达到1.25。