Showing papers on "Microstrip published in 1971"

Properties of Microstrip Line on Si-SiO/sub 2/ System

Abstract: A parallel-plate waveguide model for the microstrip line formed on the Si-SiO/sub 2/ system is analyzed theoretically and the results are compared with the experiment. The experiment has been performed over wide ranges of frequency, substrate resistivity, and strip width. Existence of three types of fundamental modes is concluded and the condition for the appearance of each mode is clarified. In particular, the slow-wave mode is found to propagate within the resistivity-frequency range suited to the monolithic circuit technology, and its propagation mechanism is discussed. Approximate analysis of the fringing effect is also made for the slow-wave mode.

Reciprocal and Nonreciprocal Modes of Propagation in Ferrite Stripline and Microstrip Devices

Abstract: An approximate analysis is presented together with a physical description of the modes of propagation in stripline and microstrip devices of significant width, using ferrite slabs as dielectric material, magnetized perpendicular to the ground plane. The dominant mode resembles TEM propagation, except that there is a strong transverse field displacement, causing wave energy to be concentrated along one edge of the line. Nonreciprocal behavior is obtainable by asymmetrically loading the edges. Approximate analytical techniques are given for isolators and phase shifters, with examples of numerical computations and experimental results.

A Frequency Dependent Solution for Microstrip Transmission Lines

Abstract: Theoretical and experimental results of "open" microstrip propagation on both a pure dielectric and a demagnetized ferrite substrate are presented. The theory enables one to obtain the frequency dependence of phase velocity and characteristic impedance, and also to obtain the electromagnetic field quantities around the microstrip line. It utilizes a Fourier transform method in which the hybrid-mode solutions for a "fictitious" surface current at the substrate-air interface are summed in such a way as to represent the fields caused by a current distribution that is finite only over the region occupied by the conducting strip and is assumed equal to that for the quasi-static case.

Microstrip ring resonator and dispersion measurement on microstrip lines

Abstract: A theory is described which takes into account the curvature of the microstrip ring resonator. This curvature is shown to have a large influence on dispersion measurements on microstrip lines with small impedences.

A New Technique for the Analysis of the Disper- sion Characteristics of Microstrip Lines

Abstract: Dispersion characteristics of shielded microstrip lines are investigated using a new technique. The method utilizes the well-known singular integral equation approach for deriving an alternate form of eigenvalue equation with superior convergence properties. It is shown that accurate numerical results may be obtained from this eigenvalue equation using only a 2x2 matrix equation. In comparison, the conventional formulation of the problem requires the use of matrices that are much larger in size. Aside from the numerical efficiency, the simplicity of the method makes it possible to conveniently extract higher order modal solutions for the propagation constants that affect the high-frequency application of microstrip lines. Even though the derivation of the determinantal equation requires some intricate mathematical manipulations, the user may bypass these completely and use the final eigenvalue equation which is programmable on the computer.

Hybrid-Mode Analysis of Microstrip by Finite-Element Methods

Abstract: A numerical analysis is presented in terms of finite elements of hybrid-mode propagation in closed microstrip. Two modes with zero frequency cutoff are described; one is a quasi-TEM mode and the other a surface mode. Also investigated is a third mode which corresponds to the lowest order waveguide mode in the absence of the strip.

A new low-loss high-k temperature-compensated dielectric for microwave applications

Abstract: A new dielectric material has been developed with a temperature-stable dielectric constant of 38. The low loss exhibited at microwave frequencies, the excellent reproducibility, and the good mechanical properties of this dielectric make it an attractive substrate for microstrip circuits. The dielectric is also suitable for the resonant elements of dielectric filters and stabilizing cavities for hybrid solid-state sources.

Variation of microstrip losses with thickness of strip

Abstract: The attenuation in microstrip lines has been calculated by relating the longitudinal components of current to the charge profiles of a static solution. The calculation has been performed for varying thicknesses of strip to examine the mechanism of loss for very thin strips, where the penetrating fields from both surfaces of the strip overlap. The results are presented in the form of a universal loss curve for the particular geometries studied, indicating the minimum thickness of strip to be used to advantage.

Applications of integrated circuit technology to microwave frequencies

Abstract: Integration techniques suitable for microwave circuits have been developed. Various aspects of the technology of integration of microwave circuits are reviewed and the reasons for choosing the hybrid approach instead of the monolithic approach and thin-film metallization instead of thick-film are discussed. Design data relating circuit performance to substrate roughness and thickness of thin-film metal adhesion layers are presented. Propagation and radiation characteristics of microstrip lines are discussed. Design equations for thin-film lumped-element passive components are given. Exampies of various microwave integrated circuits are shown.

Computation of Lumped Microstrip Capacities by Matrix Methods - Rectangular Sections and End Effect (Correspondence)

Abstract: The method of moments is applied to three-dimensional microstrip problems to calculate lumped (or excess) capacitance. As examples, the capacitance of open-circuited microstrip lines and the capacitance of rectangular microstrip sections are computed. The open-circuit data are basic to any three-dimensional problem. The method is a general one and can be used to compute the lumped capacitance of any microstrip discontinuity, such as bends and T junctions.

Analysis of Thick-Strip Transmission Lines (Correspondence)

Abstract: A method for analyzing general thick-strip transmission lines is reported. Calculated characteristic impedances based on this method are consistent with other theory and experiment in the case of thick-strip microstrip lines. The case of thick-strip lines with three dielectric layers and shielding is also presented.

Microwave stripling circuits with selectively bondable micro-sized switches for in-situ tuning and impedance matching

Abstract: A microstrip line is divided into a number of short sections, each capacitively coupled to its neighbor by a cantilever switch. The coupling of each switch depends on the separation between sections and the spacing between the catilever switch and an adjoining section. The cantilever switches are sufficiently flexible to allow test contact between adjacent sections and is permanently bondable where desired. In such a manner sections having lengths chosen to be predetermined fractions of a desired wavelength are connected together to shift the phase of energy propagating therealong to provide tuning and impedance matching of microstrip circuits.

Radiation Conductance of Open-Circuit Microstrip (Correspondence)

Abstract: The radiation conductance of an open-circuit microstrip stub is determined. The losses due to radiation from a stub are shown to be a significant fraction of the total loss.

Slow wave propagation along a microstrip line on Si-SiO 2 systems

Abstract: Experimental results that demonstrate the propagation of a slow wave mode along a microstrip line on Si-SiO 2 systems are presented. The fundamental properties of the mode are briefly discussed. The measured propagation velocity of the slow mode varies from 1/10 to 1/30 of the light velocity in vacuum depending on the line dimensions.

Junction Effects Reactance on X-Band and Dimensional Tolerance 3-Db Directional Couplers

Abstract: Theoretical characteristics are presented for X-band 3-dB rat-race and branch-line couplers using gold microstrip lines with a semi-insulating GaAs dielectric. The rat-race configuration is shown to be less influenced by junction reactance and dimensional tolerances and has a greater bandwidth than the two-branch coupler. However, the rat-race coupler has the disadvantage that the output arms are not adjacent. Three-branch couplers are shown to have bandwidth comparable to the rat-race coupler but are much more sensitive to junction reactance and dimensional tolerances.

Microstrip to microstrip transition

Abstract: A coupling arrangement for microstrip systems, each system characterized by a dielectric with a ground plane contacting one side thereof and a conductive strip fastened to the other side. A small coupling hole in the ground plane immediately underlies the strip conductor at a current maximum for signal along the line. Two such microstrip systems are placed in back-to-back relation with their ground planes in physical contact and their coupling holes in registry to transfer signal being propagated in a transverse electromagnetic mode via one of the strip conductors to the other of the strip conductors and ultimately to a desired point or points of utilization. In a specific application of the invention, the coupled microstrip systems are used to transfer signal energy from a feed network to a phased array of antenna elements.

Design of Hairpin-Line and Hybrid Hairpin-Parallel-Coupled-Line Filters

Abstract: Hairpin-line filters are compact structures particularly suited for microstrip and TEM printed circuit realizations. Two types of hairpin-line filters are described in this paper. They are shown in Figs. 1(a) and (b). The image impedance and propagation constant for the infinite periodic hairpin-line has been given previously. Equivalent circuits for several periodically-terminated lines, including the hairpin line were discussed by one of the authors at the recently-concluded IEEE sixth region conference. However, for finite length hairpin-line filters, neither exact or approximate design equations, nor equivalent circuits have been reported. The exact equivalent circuits for the filters of Figs. 1(a) and (b) have been rigorously derived and are presented in Figs. 2(a) and (b), respectively, for the most important case in which coupling beyond nearest neighbors is negligible. These circuits are topological, but not exact, duals of the well-known interdigital and half-wave parallel-coupled-line filters. Consequently, the exact design tables and approximate design equations may be used in designing hairpin-line filters.

Package for mounting semiconductor device in microstrip line

Abstract: In a microstrip line, a package for mounting a required semiconductor device between a pair of blocks of dielectric material disposed on a first conductive plate to be spaced apart a predetermined distance from each other in the longitudinally extending direction of the first conductive plate. The package is provided with electrical leads on its upper surface for establishing an electrical connection between second conductive plates disposed on the upper surface of the dielectric blocks opposite to the first conductive plate.

A Wide-Band Quadrature Hybrid Coupler (Correspondence)

Abstract: Wide-band quadrature hybrid proximity couplers consist of a conductor fabricated by thin-film techniques in microstrip the conductor side and a slot in the ground plane side. A 4 to 1 bandwidth was achieved using an alumina substrate of 99.6-percent purity with a surface finish of 10 /spl mu/in. A single-section quadrature hybrid has been fabricated and operates over a 2.5- to 10-GHz frequency range with a maximum VSWR of 1.43:1, a 20-dB typical isolation, and a phase difference between outputs of 90/spl deg/ /spl plus mn/ 3/spl deg/.

Modes in the Shielded Microstrip on a Ferrite Substrate Transversely Magnetized in the Plane of the Substrate

Abstract: The shielded microstrip on a ferrite substrate transversely magnetized in the plane of the substrate is analyzed using an appropriate modal expansion in each of the two media. The boundary conditions at the interface are then expressed in terms of two coupled integral equations which are subsequently solved by the method of moments. Information on the singularities in the fields near the edges is used in the computations to obtain the eigenvalue /spl beta/ within an estimated 0.5-percent accuracy using matrices as small as 5x5. Comparison with various published results for the microstrip is made in the lid case of a dielectric substrate. An/spl omega/-/spl beta/ plot is presented for one particular ferrite-loaded configuration which shows slight non-reciprocity in both the fundamental and higher order modes.

Radio frequency transistor package

Abstract: A transistor die is mounted over a pair of mutually opposed ceramic filled microstrip lines having a common ground plane, one of these strip lines being an input strip line and the other being an output strip line. An extention of the common ground plane member extends up through the dielectric fill material of the strip lines into the gap between the mutually opposed ends of the adjacent strip lines to form a common connector terminal. Two sets of leads interconnect the common connector terminal and the input strip line with the base and the emitter electrodes on the transistor die, whereas the collector electrode of the transistor die is electrically and thermally connected to the output strip line.

Planar r. f. load resistor for microstrip or stripline

Abstract: A planar film RF load resistor useful, in some instances, from dc up into the microwave frequency range and, in other instances, particularly useful through broadband ranges in the microwave frequency spectrum range. It is a planar thin (or thick) film RF load resistor having a smaller radius edge in conductive contact with a like shaped radius edge of an RF signal thin (or thick) film conductor, and a larger radius outer edge in conductive contact with a highly conductive film plate. The radius centers are substantially the same for the planar film RF load resistors with both microstrip and stripline units.

Resonant techniques for establishing the equivalent circuits of small discontinuities in microstrip

Abstract: The accurate measurement of small discontinuities in microstrip by conventional means is limited by the imperfections of the microstrip to coaxial transition. By using a resonant technique where such imperfections cause only 2nd-order errors, the equivalent circuit of microstrip discontinuities can be measured. To demonstrate the method, a 90° corner, with and without a chamfer, has been measured.

Substrate Transversely Magnetized in the Plane of the Substrate

Abstract: Absfracf—The shielded microstrip on a ferrite substrate transversely magnetized in the plane of the substrate is analyzed using an appropriate modal expansion in each of the two media. The boundary concMions at the interface are then expressed in terms of two coupled integral equations which are subsequently solved by the method of moments. Information on the singularities in the fields near the edges is used in the computations to obtain the eigenvalue P within an estimated 0.5-percent accuracy using matrices as small as 5X 5. Comparison with various published results for the microstrip is made in the lid case of a dielectric substrate. An@ plot is presented for one particular ferrite-loaded configuration which shows slight nonreciprocity in both the fundamental and higher order modes.

MSTRIP (Parameters of Microstrip) (Computer Program Descriptions)

Abstract: This program calculates the characteristic impedance, phase velocity, and effective dielectric constant of single or coupled microstrip lines. Parameters to be specified by the user are as follows: range of W/H/sub 1/, S/H/sub 1/, substrate dielectric constant, single or coupled lines with or without an upper ground plane.

Foreshortening of Microstrip Open Circuits on Alumina Substrates

Abstract: One particular discontinuity encountered in microstrip circuitry, the end effect of microstrip lines, is discussed. Experimental data of the end effect of 10 microstrip lines are plotted and compared with previously published data. Results reported here are consistent with that which is known about the edge effect of uniform microstrip transmission lines.

General constraints on propagation characteristics of electromagnetic waves in uniform inhomogeneous waveguides

Abstract: A unified theory is formulated for the determination of the functional behaviour in the frequency domain of the propagation constant of electromagnetic waves which may exist in a uniform inhomogeneous waveguide which contains a linear time-invariant passive medium. By applying the constraints of linearity and time invariance to a bounded uniform medium, it is shown that the propagation coefficient in the transformed frequency domain is solely a function of the complex frequency variable p. The additional physical constraints of reality and passivity are shown to imply that the propagation constant ? belongs to a special class of functions which have been termed `nonzero real functions?. If the waveguide is also dissipationless, ? becomes a `symmetrical nonezero real function? possessing symmetry about the axis p = j?. In restricted geometries for the cross-section of the guide, additional constraints on ? may exist and, as an example, a rectangular waveguide partially loaded with dielectric material is cited. A qualitative discussion on closed microstrip lines and circular waveguides containing dielectric rods is also included.

Superconducting microstrip high-q microwave resonators.

Abstract: Superconducting miniature microstrip resonators, operating at X band, have been constructed using vacuum‐deposited lead on low‐loss sintered alumina substrate. Unloaded Q's as high as 200 000 and 500 000 have been measured at 14.3 GHz at 4.2 and 1.8 K, respectively.

Deposited latched junction circulator having magnetic flux return paths

Abstract: A latching ferrite circulator utilizing deposited ferrite layers and operable without the requirement of a permanent magnet. A pair of separated ferrite layers respectively include a microstrip transmission line circuit and a ground plane on faces which oppose each other. The microstrip transmission line comprises at least one hub circuit portion and a plurality of circuit arm portions. At least two coplanar ferrite elements are deposited between the microstrip transmission line circuit and the ground plane. One ferrite element comprises the circulator element and is placed contiguous with the hub while the other ferrite element comprises a magnetic return path member which is located a predetermined distance from the circulator element. A latching conductor is located generally in the plane of the microstrip circuit intermediate the two ferrite elements so that when a DC current pulse is applied to the latching conductor, a closed magnetic circuit loop is provided through the two ferrite elements and the ferrite layers containing the microstrip circuit and the ground plane.

Coupled-mode model of dispersion in microstrip

Abstract: A coupled-mode model for dispersion in microstrip is developed which predicts dispersion for a wide range of microstrip configurations (2 ? ?r ? 104, 0.025 in ? h ? 0.125 in and 0.9 ? w/h ? 6). The expression for the coupling coefficient is derived using qualitative arguments and experimental results, and is convenient for design purposes of microstrip components.