Microstrip Line Model Research Articles

Design of Integrated Simultaneous Information and Power Receiver for WIPT Application

This letter presents the design and fabrication of a multifunctional simultaneous information and power receiver (SIPR) considering a multitone time-modulated array as wireless information and power transfer (WIPT). The proposed SIPR with Wilkinson power divider delivers power to information processing and DC generating blocks. The fabricated SIPR receives information in horizontal and vertical polarizations. A voltage-doubler-type rectifying circuit is designed for DC generation with a microstrip line model for the lumped parameter. DC generating block generates a maximum of 76% RF to DC power conversion. Furthermore, the bit error rate (BER) performance graph supports the use of the receiver for the digital modulation schemes.

Analysis of electromagnetic interaction between smooth and corrugated transmission lines by using a circuit model

It has been proved that a subwavelength periodic microstrip structure can be used to suppress crosstalk between two adjacent microstrip lines and such a microstrip structure can be widely used in the application of high-speed circuit systems. To further increase the accuracy of the equivalent circuit model of the subwavelength periodic microstrip line (SPML), we focus our attention on a single unit cell with the periodic structure, which is divided into several sub-regions, and the circuit parameters in each sub-region are analysed for setting up a complete circuit model of the unit cells. Then the details of the interaction between each sub-region and the electromagnetic field are clearly indicated. The S $S$ -parameters of the circuit model accord well with full-wave simulation results, showing a maximum deviation of 0.03973 dB for S21 and 0.1211 dB for S11 below 15 GHz. For the first time, we also study the frequency-dependence of the mutual capacitance and the mutual inductance for analysing the coupling effect between an SPML and a conventional microstrip line (CML). The instantaneous impedance obtained by the full-wave simulation of the SPML is consistent well with the experimental results.

Novel Wideband Bandpass Filters Using Double-Sided Quasi-SSPPs Transmission Line

In this brief, two wideband bandpass filters using a novel double-row staggered double-sided quasi-SSPPs transmission line are proposed. By loading U-shaped cells symmetrically, a transmission zero can be introduced into the original operating frequency band, which forms a high out-of-band suppression wideband bandpass filter. The structure can draw an analogy with double-sided parallel stripline, and the equivalent circuit model of microstrip line can be constructed to assist analysis and design. The passband selectivity can be further improved when the number of U-shaped cells is increased from 3 to 5. The measured result of 3-dB fractional bandwidth is 18.9 % (frequency 11.4 GHz), and the in-band return loss is greater than 10.2 dB. In addition, the out-of-band suppression is greater than 20 dB in the lower stopband (from 6.18 GHz to 10.12 GHz) and the upper stopband (from 12.78 GHz to 19 GHz).

Radiation Emission Source Localization by Magnetic Near-Field Mapping Along the Surface of a Large-Scale IC With BGA Package

Near-field mapping along the surface of an integrated circuit (IC) could reveal the radiated emission source inside by collecting the radiated electromagnetic field. In this article, the radiated emission source localization is first illustrated in a microstrip line model by analyzing the relationship between the physical position of the line and the hot spots of the electromagnetic field distribution along the line surface. The hot spot in each magnetic field distribution does not necessarily correspond to the physical position of the emission source due to the ground plane below. Furthermore, by analogy with the microstrip line model, the localization analysis is applied to a large-scale IC [field-programmable gate array (FPGA)] in a ball grid array package. For the demonstration, four operation states of the FPGA are designed with four general-purpose input–output (GPIO) pins outputting waveforms of different frequencies. By activating the sources in different operation states, it is found that the activated GPIO pins (as emission sources) can be located well by comprehensively analyzing the emission patterns of different components. The experimental results would be instructive to improve the understanding of IC near-field electromagnetic patterns and reasonable to localize an emission source.

Development of a Magnetic Field Probe for Near-Field Measurement

Current electronic circuits are characterised by their compact design of miniaturisation; however, such a feature has also contributed to the rise of electromagnetic compatibility issues. This study introduces a technique to develop a magnetic field probe for near-field measurement. The probe aims at performing the debugging of electromagnetic interference on an integrated circuit. Certain processes, such as designing a microstrip line in simulation and a prototype for the validation as well as developing a functional magnetic field probe for near-field scanning and calibration measurement to determine the probe factor, have been performed under a frequency domain. The microstrip line model is built both as a simulation and a real prototype, and the handcrafted loop probe is developed with the same diameter as a commercial probe. Calibration measurement is set-up with a vector network analyser (VNA) to capture the magnetic field on radiated plane. The performance of the handcrafted probe in terms of measuring the configuration of the H-field source on the scattering region is conducted. Two types of measurements which are S11 and S21 will be conducted using a VNA. The comparison of the S11 and S21 results against simulation results are plotted using MATLAB. S11 represents the return loss of the microstrip line while S21 represents the power received by the magnetic field probe relative to power input to the microstrip line. The results of the S11 parameter indicate that the customised microstrip line board has a similar waveform pattern that matches the one on the simulation model. The S21 results for the handcrafted probe revealed that it can only function well up to the frequency of 2.644 GHz, the abnormal result obtained after the frequency mentioned. Some factors may have affected the results, such as material loss, fabrication tolerance and interferences from other devices. Therefore, calibration measurement is conducted under a less reflected radiation environment, and the designated substrate should be a perfect material correlated with the measurement.

Detection of band edge frequencies in symmetric/asymmetric dielectric loaded helix slow‐wave structures

AbstractThe significant contribution of this paper is to present a comprehensive analysis and design of π‐point and band edge frequencies of reported helix SWSs including not only a microwave but also millimeter‐wave operation frequencies considering the methods in available literature which are the Coupled Mode Analysis (CMA), the Exact Floquet Approach (EFA), and the Auxiliary Functions of Generalized Scattering Matrix (AFGSM) as a comparative study. A different approach called as effective rod model is applied to circular/T‐shaped dielectric support rod helix SWSs in order to obtain ladder circuit representation of one turn of related helix SWSs for the first time. Scattering matrices of equivalent circuit representation of interested helix SWSs are obtained by using microstrip line model of helix SWS which slits helical tape at the effective helix radius along the direction normal to the helix winding direction and flattens it out for the EFA, the AFGSM, and the CMA methods. Additionally, comparisons are given for investigated methods together with the results of Computer Simulation Technology (CST) design environment, and good agreement has been observed among numerical results of different helix SWSs in a broad frequency range.

On the Modeling of Microstrip Lines Loaded With Dumbbell Defect-Ground-Structure (DB-DGS) and Folded DB-DGS Resonators

This paper presents a lumped-element equivalent circuit model of microstrip lines loaded with dumbbell defect-ground-structure (DB-DGS) resonators, etched in the ground plane. The model is valid for ordinary (i.e., unfolded) DB-DGSs, as well as for folded DB-DGSs with an arbitrary aperture angle and relative orientation between the line and the resonator. It is shown that in folded, or partially folded, DB-DGS resonators both magnetic and electric coupling between the line and the resonator should be considered, except for a particular DB-DGS orientation, namely, the one where the symmetry plane of the particle (a magnetic wall) is orthogonal to the line axis. In this case, the particle is exclusively excited by the electric field generated by the line. It is also shown that the circuit model of a microstrip line loaded with an unfolded DB-DGS resonator transversally oriented to the line can be derived from the general model by considering the effects of opening the particle, i.e., a reduction of the electric coupling. In the extreme situation where the DB-DGS is completely opened (unfolded), the electric coupling vanishes, and the particle is exclusively driven by the magnetic field generated by the line. This effect is taken into account in the model by considering that the capacitance between the line and the inner metallic region of the folded, or partially folded, DB-DGS depends on the aperture angle of the particle, and it is null when the particle is unfolded. The models are validated by parameter extraction and comparison of the circuit responses with the responses inferred by electromagnetic simulation and measurement.

Computer‐aided design‐based circuit model of microstrip line for terahertz interconnects technology

In this study, presented a computer-aided design-based circuit model which is applicable to microstrip transmission line for terahertz interconnects technology in circuit simulator. Comparison of modified Kirschning and Jansen for dispersion and modified characteristic impedance for characteristic impedance models with full-wave electromagnetic (EM) simulator are investigated which shows < 1% deviation for w/h range 0.1 ≤ w/h ≤ 100, conductor thickness 0.001 ≤ t/h ≤ 0.2, wavelength range 8.7 μm ≤ λg ≤ 8.7 m and substrate permittivity 1.0 ≤ ɛ r ≤ 200. Modified conductor loss for conductor loss and modified dielectric loss (MDL) for dielectric loss are also investigated and compared with EM simulator, which shows deviation of < 1 dB for above said electrical and physical sets of range of parameters. Calculation of line parameters: (f, t), (f, α), R(f), L(f), C(f), G(f) by using the effect of dispersion, characteristic impedance and losses which shows < 1% deviation with experimental data available. Accuracy of the circuit model are also verified for interconnects made by aluminium (σ o = 3.7 × 107 S/m), tungsten (σ o = 1.0 × 107 S/m) and tungsten–silicide (σ o = 3.3 × 106 S/m) conductors which used in very large scale integration/ultra large scale integration (VLSI/ULSI) technology.

A Switchable Bandpass Filter Employing RF MEMS Switches and Open-Ring Resonators

A switchable bandpass filter is presented in this paper, which is able to operate at two different frequencies. The “open-ring” resonators and cantilever microelectromechanical systems (MEMSs) switches are employed to form the switchable filter with a high rejection at out-of passband and a controlled dc bias of 26 V. A hybrid resonance circuit with both series circuit and parallel circuit are used as the equivalent circuit, which is used to accurately analyze the structure parameters. The MEMS switch capacitance, used for equivalent circuit and driving voltage estimation, is analyzed to achieve an exact predicted value by equivalent microstrip line model. The isolation of designed MEMS switch is greater than 40 dB with awideband from4 to 9GHz, the filter is switched on and off to achieve the center frequency at ~7.81 and ~8.35 GHz separately. The filter is fabricatedon high-resistance silicon, and the measured results showed a good agreement with the simulated results. The filter performance shows a sharp rejection greater than 40dB at the frequency of ( ${\textsf {f}}_{ { {{\textsf {0}}}}} \pm 0.5$ GHz), and the insertion loss is >−3.4 dB in the passband.

Modeling and Applications of Metamaterial Transmission Lines Loaded With Pairs of Coupled Complementary Split-Ring Resonators (CSRRs)

This letter is focused on the modeling, analysis, and applications of microstrip lines loaded with pairs of electrically coupled complementary split-ring resonators (CSRRs). Typically, these epsilon-negative (ENG) metamaterial transmission lines are implemented by loading the line with a single CSRR (etched beneath the conductor strip) in the unit cell. This provides a stopband in the vicinity of the CSRR resonance. However, by loading the line with a pair of CSRRs per unit cell, it is possible to either implement a dual-band ENG transmission line (useful, for instance, as a dual-band notch filter), provided the CSRRs are tuned at different frequencies, or to design microwave sensors and comparators based on symmetry disruption (in this case by using identical CSRRs and by truncating symmetry by different means, e.g., asymmetric dielectric loading). The design of these CSRR-based structures requires an accurate circuit model able to describe the line, the resonators, and the different coupling mechanisms (i.e., line-to-resonator and inter-resonator coupling). Thus, a lumped element equivalent circuit is proposed and analyzed in detail. The model is validated by comparison to electromagnetic simulations and measurements. A proof-of-concept of a differential sensor for dielectric characterization is proposed. Finally, the similarities of these structures with coplanar waveguide transmission lines loaded with pairs of SRRs are pointed out.

An UWB LNA Design with PSO Using Support Vector Microstrip Line Model

A rigorous and novel design procedure is constituted for an ultra-wideband (UWB) low noise amplifier (LNA) by exploiting the 3D electromagnetic simulator based support vector regression machine (SVRM) microstrip line model. First of all, in order to design input and output matching circuits (IMC-OMC), sourceZSand loadZLtermination impedance of matching circuit, which are necessary to obtain required input VSWR (Vireq), noise (Freq), and gain (GTreq), are determined using performance characterisation of employed transistor, NE3512S02, between 3 and 8 GHz frequencies. After the determination of the termination impedance, to provide this impedance with IMC and OMC, dimensions of microstrip lines are obtained with simple, derivative-free, easily implemented algorithm Particle Swarm Optimization (PSO). In the optimization of matching circuits, highly accurate and fast SVRM model of microstrip line is used instead of analytical formulations. ADCH-80a is used to provide ultra-wideband RF choking in DC bias. During the design process, it is aimed thatVireq= 1.85,Freq=Fmin, andGTreq=GTmaxall over operating frequency band. Measurements taken from the realized LNA demonstrate the success of this approximation over the band.

Modeling and Characterization of Slow-Wave Microstrip Lines on Metallic-Nanowire- Filled-Membrane Substrate

In this paper, a physical model of the slow-wave (SW) microstrip lines based on a metallic-nanowire-filled-membrane substrate is presented for the first time. The model properly predicts the behavior of the SW transmission lines as shown by the experimental results. Two sets of transmission lines differing in oxide thickness with various widths were fabricated and characterized up to 70 GHz. The electrical model is valid for both oxide thicknesses and microstrips width. High-quality factors are obtained, above 40 from 30 GHz up to 70 GHz, paving the way for further designs of passive circuits, like power dividers or hybrid couplers, with good performance.

DESIGN AND OPTIMIZATION OF EQUAL SPLIT BROADBAND MICROSTRIP WILKINSON POWER DIVIDER USING ENHANCED PARTICLE SWARM OPTIMIZATION ALGORITHM

An enhanced particle swarm optimization (EPSO) algorithm is proposed. To improve convergence accuracy and velocity, we introduce a quadratic interpolation method and perturbation to personal best particles in EPSO. Then, a design procedure based on the EPSO is proposed for the design and optimization of equal split broadband microstrip Wilkinson power dividers (MWPDs). A set of numerical examples and fabricated samples are presented to validate the improvement of the proposed EPSO. Even-odd mode analysis is incorporated in the design procedure to calculate the scattering matrix of the MWPD on the basis of the dispersion and dissipation microstrip line model. A fltness function is then constructed according to the scattering parameters. The optimized widths and lengths of microstrip lines and values of isolation resistors are directly obtained by minimizing the fltness function. EPSO is also compared with the genetic algorithm (GA), standard particle swarm optimization (PSO) and improved particle swarm optimization (IPSO).

Evaluation of tailored magnetic composite films for near-field electromagnetic noise suppression

The effects of permeability and permittivity of the magnetic nanorods filled in composite films have been studied in the broadband radio-frequency range from 0.5 to 10 GHz on a microstrip line. The transmission power absorption of the composite film on a microstrip line was simulated using 3D FEM HFSS program. The model of microstrip line was designed based on IEC standard (IEC 62333-2). The permeability of composite film with magnetic nanorods could be controlled by the aspect ratio of nanorods. The ferromagnetic resonance frequency and the relative complex permeability with the change of aspect ratio were calculated by the Landau–Lifshitz–Gilbert equation. Given the bulk magnetization of 5 kG, the power loss frequency region has exhibited the 2.5–7 GHz broadband frequency by mixing of nanorods with various aspect ratios from 2 to 10. The permittivity effects have been evaluated by changing the real part of permittivity with a fixed imaginary part value and vice versa. The power losses were increased with the proportional to the imaginary part of permittivity and did not show any significant change with the increment of the real part of permittivity. The conduction electromagnetic noise in near field can be suppressed by controlling complex permeability with various aspect ratios of the magnetic nanorods in the composite.

Broadband RF Noise Suppression by Magnetic Nanowire-Filled Composite Films

The characteristics of the electromagnetic noise suppression have evaluated using magnetic nanowire-filled composite film on a microstrip line in the broadband radio-frequency range from 0.5 to 20 GHz. The ferromagnetic resonance frequency and the relative complex permeability with the change of aspect ratio were calculated by Kittel's and Landau-Lifshitz-Gilbert equations. The FMR frequency is gradually increased with the increment of aspect ratio (up to 50) of magnetic nanowire. When the magnetic nanowires were mixed with various aspect ratio in composite, the FMR frequency exhibited the broadband frequency regions with 10-28 GHz, 5-14 GHz, 2.5-7 GHz, and 1-2.7 GHz for the change of magnetizations (4piMs: 20, 10, 5, and 2 kG), respectively. Using the calculated FMR frequency profile, the power losses were obtained in broadband frequency region. The transmission power absorption of the composite film on microstrip line was simulated using a 3-D FEM HFSS simulation program. The microstrip line model was composed of Cu conductor line and grounded dielectric substrates, which was designed by IEC standard (IEC 62333-2). The conduction electromagnetic noise was suppressed by the various aspect ratios of the magnetic nanowire-filled composite films in broadband frequency region.

Numerical analysis on power loss mechanism of Fe55Al18O27 thin films for conduction noise through microstrip line

With a simulation model of microstrip line attached by Fe55Al18O27 thin film of high magnetic loss, S parameters and power absorption has been analyzed by finite element method in the frequency range of available material parameters (0.1–1.5 GHz). It is demonstrated that the S parameters and power absorption are dominantly controlled by the electrical properties of the thin film. Although the film has a large value of magnetic loss resulting from ferromagnetic resonance, it is predicted that the power dissipation by magnetic loss is negligibly small. Simulation under assumption of high electrical resistivity shows that both S11 and S21 values approach to the value of original microstrip line. Another simulation of sheet resistance effect by film thickness control shows that higher value of power absorption is predicted in the films of small thickness mainly due to lower reflection loss. For the conductive and magnetic Fe55Al18O27 thin film, it is concluded that the dominant power loss mechanism is eddy current loss for magnetic field or Ohmic loss for electric field around the strip conductor in the frequency range investigated.

Investigation of radiated field analysis model for moment method from microstrip line on PCB

AbstractThe method of moments and the FDTD method have been widely used for the analysis of radiated electromagnetic fields. In comparison with the FDTD method, the method of moments calculates the electromagnetic field by a light computational load and analyzes the far field accurately. A wire grid model of the printed circuit board placed on the upper plane of the imitated equipment has been reported and it can calculate the electromagnetic field below 1 GHz. However, the wire grid model using the calculation above 1 GHz has not been reported. This paper proposes the analytical model that can analyze the radiated electromagnetic fields with horizontal polarization at frequencies above 1 GHz. Since the contribution of the current on a microstrip line (MSL) is significant in the case of horizontal polarization, the proposed method attempts to simulate the current distribution by inserting impedances and admittances into the wire grid model of MSL. As a result of the studies, it is found that an analysis is possible with an accuracy within ±5 dB of the measured results in the frequency range of 1 to 3 GHz when the current distribution, calculated by the FDTD method, is simulated by inserting inductance and capacitance into the wire grid model. It is also found that the result of calculation by the model is similar to that by the FDTD method, which requires a computation time about 4 times longer. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 90(8): 20–29, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20354 Copyright © 2004 Wiley Periodicals, Inc.Copyright © 2007 Wiley Periodicals, Inc.

Emulation of Propagation in Layered Anisotropic Media With Equivalent Coupled Microstrip Lines

A microstrip transmission line model is proposed for a new class of photonic crystals which exhibit a degenerate band edge (DBE). The microstrip line model is formed from a pair of coupled and uncoupled lines (one per field component, E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> and E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</sub> ) and is the first (to our knowledge) representing propagation within an anisotropic layered medium. Using the standard scattering matrix representation for the three consecutive layer sections forming the DBE unit cell, we calculate the band diagram and show that the periodic microstrip structure supports a DBE mode for a specific fabricatable design

A generalized CAD model for the full‐wave modelling of microstrip line and its regular and irregular discontinuities

AbstractIn this paper we present a new theoretical model for the modelling of the microstrip line as well as two types of discontinuities: regular (open end, step, bend and T‐ and cross‐junctions) and irregular (stub and bent‐stub). The two‐dimensional exact dyadic Green function of a grounded dielectric slab has been used with the Galerkin's technique. The subdivision of the discontinuity in a network of juxtaposed unit cells, characterized by their own longitudinal and transversal current distributions, allowed the treatment of a large class of irregular discontinuities in addition to the regular discontinuities. The obtained results have been commented and compared with those of different approaches and with experimental results where a good concordance has been observed. Copyright © 2006 John Wiley &amp; Sons, Ltd.

Characterization and Modeling of Left-Handed Microstrip Lines With Application to Loop Antennas

This study investigates in detail the left-handed (LH) properties of the two-layer microstrip line, periodically loaded with broadside-coupled split ring resonators (BC-SRRs) and vias. The mechanism of the left-handed microstrip line (LHML), which includes the diamagnetic response, the backward-wave propagation and the proportionality of the guided wavelength on frequency, is discussed in terms of the field and current distributions and the dispersion diagram. To examine the resonance of the BC-SRR, both the full-wave eigenmode analysis and the closed-form formula based on the quasistatic approach are developed. The effects of the BC-SRR shape on the resonant frequency are evaluated. To facilitate the computer-aided-design (CAD) applications of the LHML, the equivalent-circuit model, which comprises the three-conductor coupled microstrip line for the coupling section, the series LC for the BC-SRR, and the shunt inductance for the via, is established. Good agreement among the results of the full-wave simulation, equivalent-circuit model, published data, and measurement supports the usefulness of the proposed modeling methodology and also validates the analytical expressions. The application of the LHML in the microstrip rectangular loop antenna fed by the conductor-backed coplanar waveguide-to-conductor-backed coplanar stripline (CBCPW-to-CBCPS) transition is presented to highlight the unique features of the LHML. Compared with the conventional loop antenna, the LHML-loaded loop antenna achieves a 50% area reduction and the 52% of main beam steering.