Lumped Elements (lumped + element)

Distribution by Scientific Domains


Selected Abstracts


New RF extrinsic resistances extraction procedure for deep-submicron MOS transistors

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 2 2010
J. C. Tinoco
Abstract The modeling of MOS transistors used for RF applications needs the definition of a lumped equivalent circuit where the intrinsic device and series extrinsic resistances are properly evaluated. The model accuracy depends on the extraction precision of each intrinsic lumped element. In order to determine the intrinsic device behavior, it is necessary to first remove the series extrinsic resistances. For this reason their extraction becomes critical for the modeling of MOS transistors in RF circuit design. Several extraction methods have been proposed; nevertheless, the measurement noise strongly affects the obtained results. The method proposed by Bracale and co-workers is the most robust extraction procedure against measurement noise, but fails to predict correctly the series extrinsic resistances for deep-submicron devices. For those reasons, we deeply analyze the method proposed by Bracale in order to understand and then overcome its limitations. Based on those analyses, a robust extraction method for deep-submicron devices is proposed. Copyright © 2009 John Wiley & Sons, Ltd. [source]


A global time domain circuit simulation of a microwave rectenna

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 1-2 2007
Brahim Essakhi
Abstract The paper presents a global time domain simulation of a microwave rectenna studied for wireless energy transfer. The novelty of the work is to take into account both distributed electromagnetic parts of the antenna and the rectifier circuit including lumped elements. From a 3D finite element time domain electromagnetic modelling of the structure an equivalent circuit of the antenna is deduced: the input impedance is obtained as a function of frequency over a broad band. Then a rational approximation gives a corresponding PSPICE representation. The electromotive force induced between the ports of the antenna during the microwave illumination is directly computed from the 3D transient scattering problem. The resulting equivalent circuit of the antenna is finally incorporated into the electronic simulator PSPICE, together with the lumped components of the rectenna (ideal diodes and load). Thus a global non-linear time domain analysis of the whole structure becomes available. The results obtained with the methods presented in the paper are compared with those resulting from other techniques. The approach developed in the work could efficiently improve the design stage of rectennas devoted to microwave power transfer. Copyright © 2006 John Wiley & Sons, Ltd. [source]


From lumped-element circuits to monolithic integrated circuits: A contribution to RF and microwave mixer design

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 4 2005
Peter Waldow
Abstract This article deals with the mixer design for UHF-, microwave- and millimeter-wave applications. Thereby, several aspects such as the chosen technology (lumped elements, hybrid- or monolithic integration) and the applied transmission line (printed circuits, strip-, slot- or coplanar line) are considered. During the course of this contribution, the authors point out the developments in mixer design from lumped-element circuits to monolithic integrated circuits on the example of research activities in Duisburg and Kamp-Lintfort, Germany. The results of these scientific investigations, regarding both the theoretical and experimental aspects, show the feasibility of the proposed techniques. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2005. [source]


Enabling a compact model to simulate the RF behavior of MOSFETs in SPICE

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 3 2005
Reydezel Torres-Torres
Abstract A detailed methodology for implementing a MOSFET model valid to perform RF simulations is described in this article. Since the SPICE-like simulation programs are used as a standard tool for integrated circuit (IC) design, the resulting model is oriented for its application under the SPICE environment. The core of the proposed model is the popular BSIM3v3, but in this model the RF effects are taken into account by means of extrinsic lumped elements. Good agreement between the simulated and measured small-signal S -parameter data is achieved for a 0.18-,m channel-length MOSFET, thus validating the proposed model. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE 15, 2005. [source]


Analysis of microwave circuits including lumped elements based on the iterative method

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 4 2003
H. Trabelsi
Abstract The work presented here introduces lumped elements to an iterative method based on the wave concept combined with the two-dimentional fast Fourrier transformation algorithm known as fast modal transformation (FMT). We extend this method to the analysis of microwave-distributed circuits containing passive or active, linear or nonlinear lumped elements which are characterized by their surface impedance as defined in this article. Simulation results of varactor-tuned filter and phase-shifter circuit examples are compared with the measurement results. Good agreement between simulated and experimental results validates the use of the iterative method for the analysis of planar circuits, including lumped elements. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13: 269,275, 2003. [source]


Dual-band N-shaped patch antenna loaded by lumped elements

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2009
Asmaa H. Moustafa
Abstract This article presents a dual-band circular N-shaped microstrip patch antenna loaded by a shorting pin and lumped R-C circuit, hence a resonant R-L-C circuit is introduced. Loading by shorting pin excites the zero fundamental mode of the circular patch antenna (TM010), and it shifts the first fundamental mode (TM110) to higher one. N-shaped microstrip patch antenna is used as a modified circular microstrip patch antenna with reduced size. The proposed antenna is designed and fabricated on two-layered substrate. A comprehensive parametric study has been carried out on values of R and C to optimize the antenna performance. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2534,2537, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24673 [source]


Analysis of planar microwave circuits with lumped-elements by CN-FDTD

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2009
Wanchun Tang
Abstract A three-dimensional implementation of the lumped-element by Crank-Nicolson finite-difference time-domain (CN-FDTD) algorithm has been presented in this article. Several examples of planar microwave circuits with lumped resistor, capacitor, and/or inductor are simulated and compared with traditional finite-difference time-domain method and measurements. The accuracy of CN-FDTD implementation for lumped elements in this article has been verified. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 113,116, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23969 [source]


Analysis of interconnect lines using the finite-difference time-domain (FDTD) method

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2002
Nader Farahat
Abstract In this Letter the coupling effect (cross talk) in parallel microstrip interconnects is analyzed with the use of the finite-difference,time-domain (FDTD) method. The interconnects are terminated either by lumped elements or by a perfectly matched layer (PML), and the results obtained from these two methods are compared. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 6,9, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10356 [source]


MMIC medium-power amplifier in K band with matching and power-divider/combiner networks implemented with the use of lumped elements

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2002
L. Álvarez
Abstract The design and measurements of a monolithic K-band medium-power amplifier are reported. The matching, biasing, and power-splitter networks have been implemented with the use of lumped elements, reducing the chip size. The model predictions of passive circuitry have been tested through electromagnetic simulations. The amplifier has shown interesting performance in K band. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 397,400, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10334 [source]