Characterization of air-bridges in MM-wave coplanar waveguide usingthe complete mode spectrum of CPW

This paper presents a novel analysis of air-bridges in open CPW, including the effects of finite thickness metallisation, using the complete modal spectrum of the CPW. This is a technique which, in comparison with other methods, allows the common features of CPW circuitry to be extracted and preprocessed without consideration of the particular problem in hand, that is, a suitable basis upon which to build a CAD package for smaller computers. Using this approach, scattering parameters, radiation and substrate leakage patterns of isolated bridges have been derived for both types of fundamental mode incidence and compared, where possible, to those obtained from other methods. Furthermore, pairs of bridges, coupled by both the near and far fields, have been analysed     

Design and fabrication of a new micromachined interdigital coplanar waveguide

In this paper, a new micromachined interdigital coplanar waveguide (CPW) structure has been developed and its characteristics have been studied as a function of transmission line parameters. In interdigital CPW, the ground conductor is thickened by micromachining techniques which is helpful for reducing the interference between the adjacent center conductors while microwave transmits along it. Within the frequency range from 5 to 20 GHz, the return loss of this structure has two minimal values whose positions change with the structural parameters. The relative bandwidths reached 23.5% and 9.97% at 8.3 and 16.55 GHz while the insertion losses are about 0.33 and 0.5 dB/cm, respectively. The interdigital CPW is useful for designing bandpass filter and phase shifter and minimizing the whole size of microelectromechanical system (MEMS) devices.     

One- and two-dimensional coplanar waveguide structures with multiple-frequency-tuned slot resonators

In this letter, a new multiple-frequency-tuned slot resonator is introduced in coplanar waveguide (CPW) technology. Its equivalent circuit model is built up and its frequency characteristics are explained by employing the equivalent circuit parameters and field analysis. Furthermore, one-dimensional (1-D) and 2-D CPW structures with the proposed slot resonator are designed. Measurements show that the proposed CPW structures with compact size exhibit good multiple-stopband behaviours.     

A solution of coplanar waveguide with air-bridges using compleximages

A method for solving general CPW circuits including air bridges is proposed. The method generalizes the integral equation technique to nonplanar structures containing hybrid electric and magnetic currents. It also exploits the full-wave complex image technique to calculate the Green's functions of this structure efficiently. The method, therefore, offers a substantial reduction in computer time and memory over many other full-wave methods. The accuracy of the method is checked by comparing the results with available FDTD-theoretical and experimental results for a coplanar-waveguide band-reject filter. Using only 92 matching points, the method gave very good agreement     

共面波导馈电小型平面超宽带天线的设计与研究

首先提出了一种新结构共面波导馈电的小型平面超宽带(UWB)天线,该天线类似一般的共面波导馈电宽缝隙天线,为了获得超宽带工作特性,设计方案中采用了叉状结构的调谐支节,并将其辐射缝隙设计为多边形;通过数值计算研究了某些尺寸参数对天线输入特性的影响,在计算的基础上通过大量的实验详细研究了天线的频域工作特性,然后对其时域瞬时脉冲信号保真度特性进行了数值分析。计算与实验的结果表明,该天线具有超过3.2∶1的工作带宽和全向辐射特性,而且具有较好的线性相位传输特性和脉冲信号保真度,是一种有实用意义的超宽带天线。     

共面波导(CPW)馈电单极子天线的设计与研究

给出一种工作于900MHz的共面波导(CPW)馈电单极子天线的设计。该单极子天线以共面波导的中心导带为辐射单极子，以中心导带两边的金属导体作反射板，结构简单紧凑。但是由于天线与共面波导之间缺少有效的隔离，造成天线性能受共面波导尺寸的影响较严重。本文通过模拟计算和实验测量详细分析了共面波导尺寸的变化对天线性能的影响，给出了结合共面波导尺寸设计的工作在900MHz的单极子天线结构数据。     

Adaptive neuro-fuzzy inference system for gap discontinuities in coplanar waveguides

A new approach based on an adaptive neuro-fuzzy inference system (ANFIS) is presented for gap discontinuities in coplanar waveguides (CPWs). The proposed ANFIS model combines the neural network adaptive capabilities and the fuzzy qualitative approach. The ANFIS is presented so as to produce a good approximation to the nonlinear relationship between the geometrical parameters and the frequency-dependent equivalent circuit parameter (the S ₂₁ parameter of the gap). The ANFIS results for the S ₂₁ parameters are compared with the results available in the literature obtained by using the conformal-mapping technique (CMT), and the results confirm that the proposed ANFIS model can provide an accurate computation of the S ₂₁ parameters of the gaps in CPWs.     

射频微机械共面波导开关测试技术研究

通过对射频微机械共面波导(CPW)开关的工作原理进行分析，提出了一种测试射频微机械开关的电路结构。根据Cadence工作站的模拟，验征了该方案的可行性，并获得了该测试结构的优化电参数条件，为射频微机械CPW开关的测试和应用打下了基础。     

一种共面波导结构双模圆环带通滤波器

提出了一种新型的用共面波导馈线结构实现的双模圆环带通滤波器。该滤波器采用传统的圆环作为谐振器,引入阶梯阻抗作为微扰使其简并模式分离并产生耦合。这样的微扰结构我们称之为环形阶跃阻抗谐振器,它与输入/输出共面波导分别设计在介质基片的两个不同的面上。文中给出了该滤波器的结构及通过仿真和实验获得的性能参数,结果表明该滤波器在带宽为11.4%时通带内的最小插损为1.42dB。     

一种共面波导结构双模方形贴片带通滤波器

提出一种新型共面波导(CPW)结构双模方形贴片带通滤波器。该滤波器采用方形贴片作为谐振器,在方形贴片的两个对称的角上开两个相同的方形切角作为微扰使其简并模式分离并产生耦合,贴片与输入/输出CPW分别设计在介质基板的两个不同的面上。文中给出了该滤波器的结构以及通过仿真和实验获得的性能参数,结果表明该滤波器的通带带宽可在4.9%到7.4%的范围内调节,通带内的最小插入损耗为1.85dB。     

Accurate CAD model of stopping distance to compute conductor loss of CPW

The theoretical and experimentally extracted closed-form models of stopping distance are presented that provides the CAD oriented simple model to compute conductor loss of CPW with average deviation within 5.4% against the experimental results from three independent sources. Whereas the models of Holloway and Kuester has 14.6% error and model of Ponchak et al. has 17.1% error, against same sets of experimental results. The accuarcy of the models is examined in frequency range 1–120 GHz.     

Design of dual-band bandpass coplanar waveguide filter

Several recent applications in communications require filters that can operate in two or more frequency bands. The aim of this article is to exploit the advantages of coplanar waveguides (CPWs) to design a dual-band bandpass coplanar waveguide filter (DBBPF). Starting from the prototype of a two pole Chebyshev low pass filter, two frequency transformations are applied to generate the DBBPF's lumped equivalent circuit. These circuits are then implemented using compact CPW series-connected resonators patterned in the centre conductor. The designed filter operates at the two frequency bands centred at 1.7 GHz and 2.7 GHz. Measured results are obtained and compared to HFSS-simulated results with very good agreement.     

微尺度下新型MEMS滤波器的研究

分析了MEMS共面波导结构,在MEMS共面波导的基础上设计了一种MEMS滤波器,研究了它的电磁学、热应力等微尺度效应.在这些微尺度条件下分析了器件的相关性能,这些参数为获取实际的MEMS滤波器提供了一些有意义的数据.若改变设计参数,可获取其它同类型的带阻、带通滤波器件,为无线通信中的MEMS器件研究在材料选择、器件设计等方面提供了一些理论依据及其实际经验.     

应用模拟退火算法建立共面波导结构的等效电路

对中心导带和地渐变的共面波导结构提出了一种简单通用的方法,建立了其等效电路,通过模拟退火算法优化提取了电路参数.将这种方法应用于分析两种周期性共面波导结构,比较了由等效电路模型与实验得出的散射参数,得到了很好的一致性.     

非对称共面波导弯曲结构模式转换的研究

针对传统共面波导弯曲结构传输损耗较大的问题,研究了非对称共面波导弯曲结构.将时域多分辨率分析算法与从Y参数提取c模、π模特性阻抗的方法相结合,推导了二端口两种模式的散射矩阵计算公式.计算了非对称共面波导弯曲结构的传输系数.在理论分析的基础上,提出了一种测试模式间能量转换的实验装置.理论分析和实验结果证明：相对于传统共面波导弯曲结构,非对称共面波导弯曲结构的模式间能量转换更低,传输损耗更小.     

A low-loss V-groove coplanar waveguide on an SOI substrate

eguide causes about 50% less loss than the conventional one at a high frequency of up to 40 GHz.     

基于SOI衬底的低损耗V型槽共平面波导

由于SOI技术具有低损耗、低串扰等优异的电磁特性,在射频集成电路领域受到了越来越多的重视。基于SOI衬底的性能良好的无源器件对整个射频电路性能具有重要的作用。本文设计了一种基于SOI衬底的低损耗V型槽共平面波导,采用与CMOS标准工艺与硅的各向异性刻蚀技术相结合,去除了信号线与地线间距下方的SOI表层硅,实现了该传输线样品。测试结果表明,在测量的0-40GHz频率范围内,V型槽共平面波导的传输特性相比传统共平面波导有了极大改善,传输损耗减小了约50%。     

Neural models for quasi-static analysis of conventional and supported coplanar waveguides

Neural models based on multilayered perceptrons (MLPs) for computing the effective permittivities and the characteristic impedances of both the conventional coplanar waveguides (CCPWs) and the supported coplanar waveguides (SCPWs) are presented. Six learning algorithms, Levenberg–Marquardt (LM), Bayesian regularization (BR), quasi-Newton (QN), scaled conjugate gradient (SCG), conjugate gradient of Fletcher–Powell (CGF), and resilient propagation (RP), are used to train the MLPs. The results of neural models presented in this paper are compared with the results of the experimental works, the conformal mapping technique (CMT), the spectral domain approach (SDA), and three commercial electromagnetic simulators such as IE3D, CAPIND2D, and MMICTL. The neural results are in very good agreement with the theoretical and experimental results. When the performances of neural models are compared with each other, the best result is obtained from the MLPs trained by the LM algorithm.     

Right‐Angle‐Bent CPW for the Application of the Driver‐Amplifier‐Integrated 40 Gbps TW‐EML Module

In this letter we present a right‐angle‐bent coplanar waveguide (CPW) which we developed for the application of the driver amplifier‐integrated (DAI) 40 Gbps traveling wave electroabsorption modulated laser module. The developed CPW realized parallel progression of the radio frequency (RF) and light using a dielectric overlay structure and wedge bonding on the bending section. The measured S₁₁ and S₂₁ of the developed CPW were kept below ?10 dB up to 35 GHz and ?3 dB up to 43 GHz, respectively. These measured results of the CPW were in good agreement with the simulation results and demonstrated the applicability of the CPW to the 40 Gbps communication module.     

Full-wave modeling of coplanar waveguide discontinuities withfinite conductor thickness

An extended version of the spectral domain approach (SDA) is developed to analyze discontinuities in open coplanar waveguide with finite metallization thickness. By making use of the exact Green's function in the spectral domain, the effects of surface wave and radiation phenomena are accurately accounted for. Both longitudinal and transverse components of the aperture electric fields are used in the analysis to allow modelling of structures with large transverse dimensions at high frequencies. The procedure also includes mode conversion near the discontinuities. As an illustration of the method, analytical steps and computed scattering parameters of the coplanar waveguide short-circuits and transitions are provided and compared against measured data