By Topic

Microwave Theory and Techniques, IEEE Transactions on

Issue 9  Part 1-2 • Date Sept. 1994

Filter Results

Displaying Results 1 - 25 of 40
  • Comments on "The groove guide, a low-loss waveguide for millimeter waves"

    Page(s): 1716 - 1717
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (200 KB)  

    For original paper see F.J. Tischer, ibid., vol.11, pp.291-296. In the above paper, Tischer presents not only a new millimeter waveguide-the groove guide, which has been studied in recent decades-but also a new method to analyze it. However, in the paper, several conclusions he gives are wrong.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comments on "Full wave approach for the analysis of open planar waveguides with finite width dielectric layers and ground planes"[with reply]

    Page(s): 1717 - 1718
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (123 KB)  

    The paper in question [see ibid., vol. 42, p. 142-9, 1994] is claimed to be only a different formulation of the well-known Method of Lines procedure with nonequidistant discretization. This is refuted by the original authors in their reply.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comments on "An analytic algorithm for unbalanced stripline impedance"[with reply]

    Page(s): 1718 - 1721
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (423 KB)  

    Questions raised in reply to previous comments on the subject paper [Robrish] are answered with case studies performed on standard field solvers. This helps establish the accuracy of a simple equation for offset stripline characteristic impedance that is growing in popularity.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comments on "An analytical method for direct calculation of E- and H-field patterns of conductor backed coplanar waveguides"[with reply]

    Page(s): 1721 - 1722
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (214 KB)  

    In the original paper [see ibid., vol.41, p. 1606-10, 1993] there is an important algebraic simplification error. This error is evaluated. A reply is given by the originating authors.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comments on "Picosecond pulse propagation an coplanar striplines fabricated on lossy semiconductor substrates: modeling and experiments"[with reply]

    Page(s): 1722 - 1723
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (199 KB)  

    The objective of this correspondence is to point out that the propagation of picosecond pulses with superluminal speed has been reported in the original paper [see ibid, vol. 41, p. 1574-80, 1993]. A reply is given.<> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • FASTHENRY: a multipole-accelerated 3-D inductance extraction program

    Page(s): 1750 - 1758
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (838 KB)  

    A mesh analysis equation formulation technique combined with a multipole-accelerated Generalized Minimal Residual (GMRES) matrix solution algorithm is used to compute the 3-D frequency dependent inductances and resistances in nearly order n time and memory where n is the number of volume-filaments. The mathematical formulation and numerical solution are discussed, including two types of preconditioners for the GMRES algorithm. Results from examples are given to demonstrate that the multipole acceleration can reduce required computation time and memory by more than an order of magnitude for realistic integrated circuit packaging problems. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Packaging of printed-circuit lines: a dangerous cause for narrow pulse distortion

    Page(s): 1784 - 1790
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (664 KB)  

    We report here a new behavioral feature of a narrow pulse transmitted on coplanar waveguide (CPW), putting the special stress on the effects caused by the packaging of such a waveguide. This feature occurs due to the unexpected simultaneous combination of a distortion in the guided main pulse and a production of delayed echo pulses. An explanation based on a new class of the dominant-mode power-leakage effect leads to a clear physical understanding of why such features necessarily appear View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Voltage pulse forming dynamics in a transmission line section employing photoconductive charging and discharging

    Page(s): 1632 - 1637
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (504 KB)  

    Studies are presented of voltage pulse generation by triggering the charge and discharge cycles of a transmission line section using photoconductive switches. A simple theoretical model is used, from which design criteria and optical power requirements are established that enable a) the section to achieve full charge, and b) complete discharge of the section to yield a rectangular pulse with a background voltage level of 5% or less. It is shown that these conditions can be achieved when The ratio of the charging switch and discharge switch peak conductances is approximately equal to the ratio of the line transit time and photoconductor recovery time. With this ratio low, the charging switch length can be increased to improve the bias voltage hold-off characteristics, while the additional optical energy needed is minimal. A formula for the maximum repetition rate is derived that demonstrates significant improvement over devices that employ passive charging. Experimental results on a microstrip device are presented, and are compared to the model predictions View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Multilevel optimization of high speed VLSI interconnect networks by decomposition

    Page(s): 1638 - 1650
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (900 KB)  

    A multilevel optimization technique is developed for large-scale and hierarchical optimization of high-speed VLSI interconnects modeled by distributed transmission lines. Mathematical programming decomposition is combined with network tearing where the overall network is optimized by a set of parallel suboptimizations. The technique takes advantage of VLSI interconnects in the hierarchy of IC, multichip modules (MCM) and printed circuit board (PCB), and is faster than standard optimization. The convergence property of the technique is derived through Gauss-Seidel relaxation analysis and optimality conditions for the multiple suboptimizations View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis of packaged microwave integrated circuits by FDTD

    Page(s): 1796 - 1801
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (604 KB)  

    The behavior of packaged single and coupled MMIC via-hole grounds has been investigated by using a graded mesh FDTD code running on the massive parallel computer DEC 12000 with 4 K processors. Theoretical simulations have been compared with experimental measurements showing excellent agreement. Moreover, since the package introduces resonances, we have also investigated several different possibilities to choke off these resonances. It is shown that the common practice of inserting a damping layer just below the lid is often not effective. In particular, the importance of placing damping layers also on the side walls is demonstrated View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Theoretical and experimental analysis of channelized coplanar waveguides (CCPW) for wideband applications of integrated microwave and millimeter-wave circuits

    Page(s): 1651 - 1659
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (756 KB)  

    A quasi-planar structure called Channelized Coplanar Waveguide (CCPW) is proposed for wideband applications of integrated microwave and millimeter-wave circuits. Compared with the conventional coplanar waveguides, the novel transmission line has a narrow metallic notch channel located underneath the main guiding part, which is able to provide direct grounding equalization without resorting to via-holes or the use of air-bridges. In addition, an electrically shielding condition, based on the theoretical principle of the nonradiative dielectric waveguide, is proposed to suppress radiation losses and reduce leaky-wave propagation in conjunction with the umbilical channel. Some interesting phenomenons regarding the electrically shielding condition are experimentally observed. One attractive feature of the proposed CCPW is its ability to drive higher-order modes towards higher frequency range, and therefore demonstrates a potential for wideband applications. A method of lines with vertical discretization scheme is used to accurately determine dispersion characteristics of the proposed CCPW and influence on mode propagation including higher-order modes. Theoretical results of dispersion are verified experimentally over large frequency band of interest View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Demonstration of the waveguiding properties of an artificial surface reactance

    Page(s): 1695 - 1699
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (380 KB)  

    We define a surface capacitive reactance as the limit of a dielectric sheet of thickness h and dielectric constant ε, when h tends toward zero and ε tends toward infinity in such a way that the product ε¯=εh remains constant and finite. It is easy to prove that such an ideal surface capacitive reactance supports a single guided electromagnetic mode of the transverse electric (TE) type, with a very simple field profile. In this paper, we show that a fair approximation of an ideal surface capacitive reactance in the microwave domain can be realized artificially by depositing suitable metal patterns on each face of a dielectric sheet with a moderate dielectric constant. By using a two-dimensional resonator technique, we demonstrate that this artificial surface capacitive reactance bears the electromagnetic guiding properties expected for an ideal surface capacitive reactance. Application of this device to a new type of mechanically tuned resonator is briefly discussed View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis of microwave capacitors and IC packages

    Page(s): 1759 - 1764
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (524 KB)  

    This paper presents quasi-static electromagnetic (EM) models for analysis and design of microwave capacitors and integrated circuit (IC) packages. The theoretical background for modeling of open 3-D boundaries with finite difference method (FDM) is reviewed and the use of current simulation method (CSM) for inductance computation is proposed. Computed data for the capacitance and inductance of capacitors with complex three-dimensional geometries are verified both numerically and experimentally, validating the proposed quasi-static models. Numerical results for practical devices and IC packages are also given View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Source-pull measurements using reverse six-port reflectometers with application to MESFET mixer design

    Page(s): 1589 - 1595
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (600 KB)  

    A new experimental technique using six-port reflectometers, operated in reverse configuration, suitable for source-pull device characterization is reported. Analytical analysis and experimental verification show that using the six-port in reverse configuration allows the impedance of the test port of the six-port junction to be measured. This measurement technique is suitable for the design of low noise amplifiers and of active nonlinear circuits such as FET mixers and power amplifiers. This measurement technique has been used for the first time to study: 1) The effect of the LO and RF impedances of the input matching circuit of a MESFET gate mixer on the LF output power and conversion gain. 2) The effect of the phase of a LO offset short circuit presented to the MESFET output on the DC power efficiency and the conversion gain of the gate mixer. Experimental results of a NE-72084 GaAs MESFET gate mixer demonstrate that by presenting to the MESFET the optimum input RF and LO impedances and the right phase for the LO offset short-circuit at the output, 2.5 dB conversion gain can be achieved with a 2.5 times reduction of DC power consumption as compared to conventional design approaches View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Silicon monolithic MM-wave integrated circuit (SIMMWIC) devices mounted up-side-down on a copper heat sink integral with cavity resonator

    Page(s): 1837 - 1841
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (364 KB)  

    Silicon monolithic MM-wave integrated circuits (SIMMWIC) used as oscillators in radar system applications in the 60-80 GHz regime are mounted on a heat sink with integrated resonator. The heat sink consists of a thin carrier plate (aluminum nitride (AlN) or copper (Cu)) and and a gold plated copper block with integrated resonator cavity. The resonator cavity is formed by a rectangular cavity milled in the Cu block, terminated on the top by the gold plated carrier plate on top of which a MM-wave emitting integrated coplanar slot-transmitter is mounted up-side-down. The main part of the emitted RF power is radiated through the substrate-perpendicular to the chip plane-the other part is coupled through a slit on the carrier plate into the resonator cavity leading to a higher spectral purity and a stabilization of the oscillating frequency View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A field theoretical derivation of TLM

    Page(s): 1660 - 1668
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (628 KB)  

    A field theoretical foundation of the TLM method is presented in this paper. In the derivation of the condensed symmetric TLM node, the Method of Moments is applied to Maxwell's equations to obtain discretized field equations. It is shown that the traditional mapping between wave amplitudes and electric and magnetic field components incorporates serious problems. Therefore, a new mapping between the wave amplitudes and the electric and magnetic field components is introduced. Applying the new mapping to the discretized field equations, the fundamental equations of the three-dimensional TLM method with condensed symmetric node are derived from Maxwell's equations View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Characterization and modeling of multiple line interconnections from time domain measurements

    Page(s): 1737 - 1743
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (568 KB)  

    Methods have been developed to extract electrical circuit models from time domain measurements of lossless, nonuniform, multiconductor transmission lines for two broad classes of structures. Although unique solutions are not feasible for general structures that scatter the propagating wave-front, approximate solutions have been identified. For the first class of structures a single velocity wave-front is assumed, equivalent to the homogeneous media case. The second class is for structures with identical lines, such as a parallel line bus structure, where separable modal wave-fronts propagate. For these cases the propagation behavior (eigenvector matrix) is determined only by the known number of lines, N, allowing decoupling of the system into N orthogonal modal transmission lines. Circuit models have been developed for these decoupled nonuniform lines, as well as for the equal modal velocity assumption which relies on a matrix impedance profile to fully describe the system View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Quasi-static conductor loss calculations in transmission lines using a new conformal mapping technique

    Page(s): 1807 - 1815
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (744 KB)  

    A new approximation technique to find the total series impedance per unit length for quasi-TEM transmission lines including conductor loss has been developed. It is shown through the use of conformal mapping that both frequency dependent skin-depth and proximity effects can be accurately modeled. Comparison between experimental measurements and calculations for twin-lead, coplanar strips, parallel square bars, and coplanar waveguide all show excellent agreement. This technique is easily generalized to any transmission line making use of polygonal cross-section conductors View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Circular and annular sector planar components of arbitrary angle for n-way power dividers/combiners

    Page(s): 1617 - 1623
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (476 KB)  

    Previously derived Green's function for circular and annular sectors restricted the sector angle to an integer submultiple of nπ. In this paper, using the single series Green's function approach, the Green's function is shown to hold for arbitrary sector angles. The removal of this restriction enables an effective sector angle to be introduced, which then can be used to account for the fringing fields. It is shown that the fringing fields at the straight edges of the sector are responsible for the unequal power division obtained experimentally, and thus by accounting for the fringing fields in the design, it is possible to eliminate the unequal power division. Experimental and theoretical results are in good agreement View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis and experimental validation of a type of three-microstrip directional coupler

    Page(s): 1624 - 1631
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (676 KB)  

    This paper presents an efficient analysis of a semi reentrant microstrip coupler section. The structure provides tight coupling while maintaining all connections at the same plane. The scattering parameters of this coupler were obtained in the past using the even-odd mode theory. This paper shows that three, rather than two, fundamental modes should be considered in a general situation, since the even-odd mode theory is inaccurate in certain cases. The coupler quasi-TEM parameters are computed by using an enhanced version of the spectral domain technique. Thus, the synthesis of the coupler is carried out in seconds using a personal computer. A rigorous full-wave analysis has also been implemented to ensure that dispersion is negligible. Experimental validation of theoretical conclusions is included View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Microstrip to waveguide transition compatible with MM-wave integrated circuits

    Page(s): 1842 - 1843
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (196 KB)  

    Microstrip to waveguide transitions used presently typically require a relatively complex waveguide mount extending on both sides of the planar circuit. Additionally, the planar substrate has to be cut into specific forms limiting the flexibility of the planar circuit design and complexity. In this paper, a new type of transition is described based on the principle of slot coupled antennas radiating into the waveguide. In this way, the extension of the planar circuit is not restricted, and at the same time, the involved antenna element can be used to hermetically seal the microwave/MM-wave input View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • One-way equation absorbing boundary conditions for 3-D TLM analysis of planar and quasi-planar structures

    Page(s): 1669 - 1677
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (684 KB)  

    Absorbing boundary conditions based on one-way wave equations (formulated by Higdon for FD-TD analysis) have been investigated and implemented for the 3-D Symmetrical Condensed Node TLM analysis of dispersive microwave and millimeter-wave structures. Very low reflections over a wide frequency band have been obtained by concatenating two and three first-order boundary operators. Numerical stability of the absorbing boundary conditions with different discretizations of the boundary operators (derivatives) has been studied. It has been found that numerically stable algorithms can be obtained with proper discretizations. These excellent stable absorbing boundary conditions can considerably reduce the computational domain, thus making possible the 3-D TLM analysis of planar and quasi-planar structures with moderate computer resources. The scattering parameters computed using these boundary conditions for microstrip via holes and shorting pins compare well with the available data View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Stationary phase Monte Carlo path integral analysis of electromagnetic wave propagation in graded-index waveguides

    Page(s): 1709 - 1714
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (476 KB)  

    The stationary phase Monte Carlo (SPMC) path integral method is applied to analyze electromagnetic wave propagation in transversely inhomogeneous media. A filter, which gives a stable result with respect to various Monte Carlo parameters and thus overcomes the difficulties previously associated with the multi-dimensional SPMC technique, is constructed to evaluate the propagation field. Numerical results are presented for a graded-index waveguide, and are in good agreement with those obtained by another independent path integral approach, viz., the split-step method View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Spectral method for modes excitation problem in anisotropic waveguides

    Page(s): 1685 - 1689
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (328 KB)  

    In modes excitation problem of anisotropic waveguides attention should be paid to the case of excitation sources with longitudinal components. In such case the usage of the basis of membrane functions of normal modes for the solution of the excitation problem may not lead us to unequivocal results because only transverse components of modes fields form a complete set of orthonormal basis on the waveguide cross section. In this paper it is shown that in the presence of longitudinal currents it appears the additional terms in the excitation integral caused with as anisotropy of medium as the transversal derivatives of longitudinal currents View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Dipole excitation and scattering by spherical objects in GTEM cell

    Page(s): 1700 - 1708
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (720 KB)  

    The GTEM (GigaTEM) cell is proving a useful tool for characterizing the EM emission of objects under laboratory conditions. In order to enhance its practical use, however, it is essential to be able to identify and predict differences between tests in “open site” and in cell environment. The modes of the empty cell were previously reported. In this contribution, we address in the first time the problem of excitation by dipoles in the non uniform environment of the cell. Moreover, we present an analytical model of the scattering by a dielectric or conducting sphere in the cell. Numerical results are compared with experimental data, when possible, and with theoretical results for scattering by the same object in free space, showing very good agreement as regards the resonant frequencies View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

The IEEE Transactions on Microwave Theory and Techniques focuses on that part of engineering and theory associated with microwave/millimeter-wave components, devices, circuits, and systems involving the generation, modulation, demodulation, control, transmission, and detection of microwave signals. This includes scientific, technical, and industrial, activities. Microwave theory and techniques relates to electromagnetic waves usually in the frequency region between a few MHz and a THz; other spectral regions and wave types are included within the scope of the Society whenever basic microwave theory and techniques can yield useful results. Generally, this occurs in the theory of wave propagation in structures with dimensions comparable to a wavelength, and in the related techniques for analysis and design..

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Dominique Schreurs
Dominique.Schreurs@ieee.org

Editor-in-Chief
Jenshan Lin
jenshan@ieee.org