Three-conductor Transmission Line Research Articles

Wideband Absorbing Metasurface for Improving Axial Ratio of a Compact Archimedean Spiral Antenna

A wideband absorbing metasurface is proposed to improve the circularly polarized response of a 1–18 GHz low-profile Archimedean spiral antenna. The metasurface consisting of surface-mounted resistors between metallic patches in a circular arrangement is placed on the opposite side of the antenna substrate. After analyzing the unit cell behavior under an equivalent three-conductor transmission line, a concentric arrangement of the metasurface under the spiral is proposed. This metasurface is designed to absorb the edge-reflected waves to improve the circularly polarized response of the antenna below 6 GHz. The antenna substrate with the metasurface is placed above a flat conductor that makes an overall antenna height of 5 mm. After numerical investigations, a prototype is fabricated and characterized. The measured right-hand circularly polarized gain is positive above 2 GHz with a maximum gain of approximately 8.7 dBic at 10.6 GHz. An axial ratio (AR) better than 3 dB is observed above 1.125 GHz. The benefits of the metasurface compared to a commercially available absorbing material are highlighted, and its usefulness to design a compact spiral antenna is presented.

A Method for Diagnosing Soft Short and Open Faults in Distributed Parameter Multiconductor Transmission Lines

This paper aims to develop a method for diagnosing soft short and open faults occurring in a distributed parameter multiconductor transmission line (DPMTL) terminated at both ends by linear circuits of very high frequency, including lumped elements, which can be passive and active. The diagnostic method proposed in this paper is based on a measurement test performed in the AC state. To write the diagnostic equations, the DPMTL is described by the chain equations in the frequency domain. For each considered fault, the line is divided into a cascade-connection of two lines, and a set of the diagnostic equations is written, taking into account basic circuit laws and the DPMTL description. This set includes nonlinear complex equations in two unknown real variables consisting of the distance from the beginning of the line to the point where it occurs and the fault value. To solve these equations, a numerical method has been developed. The procedure is applied to the possible soft shorts that can occur between all pairs of the line conductors, and the actual fault is selected. The method has also been adapted to the detection and location of open faults in DPMTL. Numerical examples, including three-conductor and five-conductor transmission lines, show that the diagnostic method is effective and very fast, and the CPU time does not exceed one second.

A 60-GHz SiGe Power Amplifier With Three-Conductor Transmission-Line-Based Wilkinson Baluns and Asymmetric Directional Couplers

A compact, 60-GHz high-power, wideband balanced power amplifier, implemented in a 90-nm SiGe BiCMOS technology, is demonstrated. A three-conductor transmission-line-based asymmetric coupled-line directional coupler is used to achieve impedance transformation and quadrature power combining simultaneously. A Wilkinson balun based on a three-conductor transmission line structure is implemented to achieve a four-way series-parallel power combining. Analyses of the three-conductor asymmetric coupler and the Wilkinson balun combiner are provided in this article. The design achieved 17.3-dB small-signal gain, with 41.8-GHz 3-dB bandwidth, from 28.1 to 69.9 GHz. A 24.4-dBm saturated output power (PSAT) was measured at 60 GHz with a 22-GHz 1-dB P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SAT</sub> bandwidth, covering 45-67 GHz. The circuit showed a peak power-added efficiency (PAE) of 14.2% at 60 GHz, and the peak PAE is above 11.5% across the 1-dB P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SAT</sub> bandwidth. The proposed eight-way power combining scheme achieves 0.077-mm2 per-way area consumption and 449-mW/mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> power density.

An Extended Solution to the Equations Describing a 3-Conductor Transmission Line

The full derivation of the generalized and extended solution to the equations describing threeconductor Transmission line is given in this paper; the brief results are presented in a previous paper. The Considerations proceed from the c. Paul formulation of lossless transmission lines terminated by linear loads. In contrast to c. Paul, the conjoint interaction between the two lines is considered here and the influence of the Receptor line is not neglected, that is the weak-coupling approximation is not applied. In result, an extended and Generalized mathematical model compared the original model of c. Paul is obtained. In particular, a mixed Problem for the hyperbolic system describing the three-conductor transmission line is formulated. It is shown That the formulated mixed problem is equivalent to an initial value problem for a functional system on the Boundary of hyperbolic system’s domain with voltages and currents as the unknown functions in this system Are the lines’. The system of functional equations can be resolved by a fixed-point method that enables us to Find an approximated but explicit solution. The method elaborated in this paper might be applied also for linear As well as nonlinear boundary conditions.

Методика экспериментального поиска укрупненных первичных параметров трехпроводной линии электропередачи

Finding the outcomes of transmitting electricity through a power line from the source to a consumer requires accurate information on the parameters of this line. Finding these parameters for operating lines with a minimum error is a resource-intensive problem. But if a researcher is interested only in voltages and currents at the end and at the beginning of a homogeneous section of a three-conductor transmission line, then it is sufficient to use the theory of multipoles, in particular, the theory of eight-terminal circuits. The article presents a method for finding the longitudinal and transverse parameters of a transmission line experimentally. The study employs in-kind experimentation on an appropriate fleet of electrical devices, as well as indirect measurement of the desired values. The experimental has a six-step design; obtained data help quantify the primary parameters on a selected PTL section to further correlate the inputs and outputs for the section. Besides, the method can be used for analysis of active eight-terminal circuits of a similar design. This means that the proposed technique enables comprehensive analysis of a studied facility. The article presents the diagram of the pilot plant, describes the experiment design, and presents error calculations based on the obtained experimental output.

Theory, Simulation, and Experiment on Extended Mixed-Mode S-Parameters in Three-Conductor Lines

This paper proposes novel mixed-mode S -parameters, which are dubbed as “extended mixed-mode S -parameters.” The extended mixed-mode S -parameters were applied to three-conductor transmission lines, resulting in the independent differential and common modes using the current division factor of three-conductor transmission lines. By contrast to the conventional mixed-mode S -parameters, there are no cross-mode S -parameters in the extended mixed-mode S -parameters, even in the asymmetrical conductor transmission lines. In addition, two new mode conversion matrices, which contain the current division factor, are also proposed to convert the extended mixed-mode S -parameters to the standard S -parameters. The validity of the proposed extended mixed-mode S -parameters and the mode conversion method were confirmed by comparing the S -parameters from the theory, EM-simulation, and experiment as well.

Lumped and Distributed-Parameter Circuit Models of the Electromagnetic Clamp

This paper presents two circuit models of the electromagnetic (EM) clamp defined in Standard IEC 61000-4-6 for conducted-immunity (CI) testing. First, a lumped-parameter circuit model is extracted from measurements of scattering parameters. This model is merely behavioral since it provides a valid representation of the EM clamp at external ports up to 1 GHz, whereas physical interpretation of the involved sources/impedances is possible under 10 MHz only. To extend physical insight at higher frequencies, a distributed-parameter circuit model is proposed, which is based on the description of the internal structure of the EM clamp as a three-conductor transmission line. Unknown model parameters (such as the magnetic permeability of ferrite rings) are identified by optimized fitting of ad hoc measurements. Both models are eventually validated by experiments performed in an idealized CI test setup. Several observations on the operating principles and features of the EM clamp are inferred from the two complementary modeling approaches.

New differential-mode-source cable bundle crosstalk model based on multiconductor transmission lines theory

The traditional cable bundle crosstalk model is established based on an intra-system common mode source, without considering the crosstalk of cable bundles stimulated by a differential-mode source between different systems. To solve the physical problem of crosstalk between independent circuit cable bundles which is stimulated by a differential-mode source, in this article we propose a new differential-mode source cable bundle crosstalk calculation method based on the multiconductor transmission line theory. According to the mechanism of the differential-mode-stimulated transmission line coupling, using this method we obtain a new three-conductor transmission line parasitic parameter circuit model and mathematic matrix model through using the transmission line propagating transverse electro magnetic mode. We deduce the parasitic parameter calculation formula by an image method and Neumann formula, and then obtain the new cable bundle crosstalk chain parameter array equations in frequency domain. By using the top and end boundary conditions of the new differential-mode cable bundle crosstalk model, we finally work out the crosstalk voltage in frequency domain. In this article, we take the crosstalk between differential-mode parallel double culprit cables and the victim cable from other independent circuit for example. By simulating the crosstalk voltage of victim cable in different position arrangements, we obtain the crosstalk physical law between cable bundles under the differential-mode source condition, that is, the crosstalk of the victim cable located between differential-mode circuits is much larger than that situated outside the differential-mode circuit. We can also verify that this model can be used to calculate the crosstalk caused by differential-mode source at different frequencies. In this article, we analytically calculate the crosstalk problems caused by differential-mode source cable bundles for the first time, which provides theoretical basis for solving some practical electromagnetic compatibility problems such as the bundling of a large quantity of wires and the predicting of cable bundle crosstalk. Therefore it perfects the application of multiconductor transmission line model to cable bundle crosstalk problem, and has strong guiding significance.

A New Approach for Closed-Form Transient Analysis of Multiconductor Transmission Lines

A novel closed-form model for multiconductor transmission lines is presented. The proposed model is derived from the analytical characterization of half-T ladder networks, which using closed-form polynomials (named DFF and DFFz), allow one to exactly extract poles and residues of the two-port representation of multiconductor transmission lines, thus, generating a time domain macromodel that can be incorporated in a circuit simulator. Since the model is derived from a stable and passive equivalent network, its stability and passivity are strictly preserved. Simulation results for one, two, and three-conductor transmission lines with linear and nonlinear terminations are presented, confirming the validity of the proposed model.

Characterisation of crosstalk in terms of mean value and standard deviation

A probabilistic model is developed for the characterisation of crosstalk sensitivity to random fluctuations of conductors in a bundle cross-section. A uniform and lossless three-conductor transmission line (TL) is used for the definition of generator and victim circuits, with general loading conditions. A novel circuit model for crosstalk is developed, in which the victim circuit embeds all the interference effects due to the presence of the generator circuit. Such effects are represented by a voltage and a current lumped noise-source and a distributed-parameter passive two-port. Under the weak-coupling assumption, and by assuming random fluctuations of the generator wire in the TL cross-section, closed-form expressions for the mean value and variance of crosstalk voltages are derived, valid both at low-frequencies and in the TL standing-wave region. These closed-form crosstalk estimators extend previous results, limited to electrically short TLs. All the theoretical developments are checked via a numerical repeated-run analysis.

Simulation lossless symmetrical three conductor systems

The treatment of symmetrical lossless three-conductor transmission lines with arbitrary terminations and umped coupling elements is reduced to a set of four delay elements and analog interface networks modeling the mode conversion in unsymmetrical terminations or coupling elements between the lines. The model can easily be programmed in circuit simulators like SPICE using the respective transmission line models in combination with the above-mentioned interface networks. Crosstalk between bus lines is discussed as an example.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Calculation of electrical parameters of a thin-film multichip package

The calculations of the electrical parameters of a thin-film multichip package are presented. It is shown that a commonly used 2-D device simulator, PISCES, can be used to compute the electrical parameters of the thin-film lines up to a frequency where the skin effect is important. For trapezoidal conductor cross-sections, it is shown that the maximum variations of self- and mutual (coupling) capacitances are within 10% of their corresponding rectangular values when the sidewall angle of the conductor is varied up to 30 degrees , and the line cross-section area is kept constant. For the case when the conductor base is kept constant, the variation in mutual capacitance is found to be within 30% and that for self-capacitance is found to be within 12% when the sidewall angle is varied up to 30 degrees . A simple R-L-C circuit is used to represent a three-conductor lossy transmission line system, and SPICE is used to analyze the responses in the time domain. A thin-film multichip package design is briefly outlined. A HP-8510 network analyzer is used to verify the simulation results. >

Estimation of Crosstalk in Three-Conductor Transmission Lines

A simple method for sketching the frequency response of crosstalk in three-conductor transmission lines is presented. The line is composed of three perfect conductors immersed in a lossless homogeneous medium. The method allows one to obtain a logarithmic asymptote plot (Bode plot) common to automatic control and electric circuit problems. In addition, it is shown that the maximum crosstalk may occur for frequencies where the line is electrically short. The magnitude of this maximum crosstalk can be estimated from the plot.

Experimental Characterization of Partially Degenerate Three-Conductor Transmission Lines in the Time Domain

In a recent paper [1], a method for the time-domain characterization of lossless multiconductor transmission lines with cross sectionally inhomogeneous dielectrics was presented. This method is limited to lines with completely nondegenerate propagation; i.e., all the modes have distinct propagation velocities. In this paper, a method is presented for the characterization of lossless partially degenerate three-conductor lines, together with experimental data. The results are in good agreement with independent frequency-domain measurements.

Comments on "On the properties of the product of the impedance and admittance matrices of three-conductor transmission lines"

Comments on "On the properties of the product of the impedance and admittance matrices of three-conductor transmission lines"

On the properties of the product of the impedance and admittance matrices of three-conductor transmission lines

The purpose of this letter is to show that the product of the impedance and admittance matrices of three-conductor transmission lines is never in the form [aa,b0] or [aa,0b] when s = jω The significance of this result is discussed.

Hybrid Computer Simulation of Multiterminal DC Power Transmission Systems

Techniques are developed for the hybrid computer simulation of multiterminal dc power transmission systems with two- or three-conductor transmission lines. The switching of the static converters as well as the attenuation and transport delay of a distortionless transmission line are represented in detail. An example study is performed using a hybrid simulation of a singlepole three-terminal system, wherein the converter terminals are represented on the analog portion and the transmission line is represented on the digital portion of the hybrid computer. Results include waveforms for the transient behavior of the system during line faults on each of the three transmission branches.

Skin Effect and Proximity Effect in Polyphase Systems of Rectangular Conductors Calculated on an RC Network

The parameters of polyphase transmission lines consisting of two or three equal parallel rectangular conductors are calculated for low and high frequencies. An analog RC network with about 3300 nodes has been built which allows the diffusion equation and Laplace's equation in an infinite plane to be solved, and which lends itself favorably to the method of virtual displacement, too. From measurements on this network, the coefficients of resistance and internal inductance per unit length are given for the even and odd modes of two-conductor transmission lines and for Clarke's ?-s-0 components of three-conductor transmission lines. The results can be used to calculate the influence of proximity effect on resistive and inductive losses in busbar systems and cables with rectangular conductors carrying arbitrary phase currents. Besides these results, methods are indicated to determine the capacitance per unit length, the electric and magnetic fields, and the magnetic forces between current-carrying conductors by means of the analog network. It is believed that the method for direct measurement of serial losses and the curves in Figs. 4?10 for the proximity effect of rectangular conductors are new.

Transmission Characteristics of a Three-Conductor Coaxial Transmission Line with Transpositions

This paper describes in detail the manufacture of, measurements on, and computations about a three-conductor coaxial cable with transpositions. By reducing skin-effect losses in the central conductor, this three-conductor line achieves 17 per cent lower attenuation at a particular frequency than does a two-conductor line of the same outer diameter. The matrix method used for analysis can easily be extended to n-conductor lines. Suggestions for making improved three-conductor coaxial lines are made.

Characteristic Impedance of Parallel Wires in Rectangular Troughs

The method of conformal transformation and the method of images are employed jointly to deduce the characteristic impedance of a balanced two-conductor transmission line and of a balanced three-conductor transmission line symmetrically surrounded by perfect, rectangular, grounded, conducting surfaces. It is assumed that 1, the wires are of circular cross section, of diameter small compared to the distance between them and small compared to the distance from the wire to any side of the surrounding surface, and 2, the wires are perfect conductors.