Sat, 19 Jul 2008 03:05:32 BST CiteULike: dcastro's circuit http://www.citeulike.org/user/dcastro/tag/circuit CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dcastro/article/2920520 <i>Microwave and Wireless Components Letters, IEEE, Vol. 18, No. 1. (2008), pp. 25-27.</i><br /><br />A broadband quadrature power splitter (QPS) is developed using the metamaterial transmission line (MM TL). It consists of a Wilkinson power divider and two phase-adjusting TLs, namely a MM TL and a microstrip (MS). The slope of the phase-response curve of the MM TL is synthesized to be the same as that of the MS along with the 90deg phase increment at two design frequencies. Hence, the broadband quadrature phase difference over the desired frequency range can be obtained. In this letter, the QPS is developed at the center frequency of 2 GHz. Over the frequency range of 1.1-3.5 GHz, an amplitude imbalance of less than 0.9 dB and a phase error of less than plusmn5deg have been experimentally demonstrated. A Broadband Quadrature Power Splitter Using Metamaterial Transmission Line Chao-Hsiung Tseng Chih-Lin Chang doi:10.1109/LMWC.2007.911981 Microwave and Wireless Components Letters, IEEE, Vol. 18, No. 1. (2008), pp. 25-27. 2008-06-24T07:20:16-00:00 2008 Microwave and Wireless Components Letters, IEEE 18 1 25 27 broadband circuit divider metamaterial power http://www.citeulike.org/user/dcastro/article/2836658 <i>European Microwave Conference, 1975. 5th (1975), pp. 268-272.</i><br /><br />A method for determining the accuracy of computed impedance and wavelength data for microstrip is proposed. It is shown that the standard equations of Wheeler and Schneider have rather large errors. Revised equations for microstrip impedance and wavelength are given both for analysis and synthesis with accuracy better than 1%. A simple, accurate equation for the microstrip open circuit is presented. Experimental data on microstrip T-junctions are compared with existing theories. A new accurate equation is given for the reference plane displacement in the stub arm. Corrections are proposed in the existing equations for the other parameters of the equivalent circuit. Equations for Microstrip Circuit Design Erik Hammerstad doi:10.1109/EUMA.1975.332206 European Microwave Conference, 1975. 5th (1975), pp. 268-272. 2008-05-27T07:08:15-00:00 1975 European Microwave Conference, 1975. 5th 268 272 circuit design microstrip http://www.citeulike.org/user/dcastro/article/2801962 <i>Microwave Symposium Digest, 2001 IEEE MTT-S International, Vol. 2 (2001), pp. 1011-1014 vol.2.</i><br /><br />This paper points out that appropriately trained artificial neural networks can be used to develop knowledge-aided-design (KAD) modules for RF and microwave design. The approach is illustrated by examples of the reflection type and the loaded line type phase shifters. It also is applicable to other types of circuits and subsystems. KAD modules were developed and verified by using available microwave CAD software An approach for knowledge-aided-design (KAD) of microwave circuits using artificial neural networks R Zingg KC Gupta doi:10.1109/MWSYM.2001.967063 Microwave Symposium Digest, 2001 IEEE MTT-S International, Vol. 2 (2001), pp. 1011-1014 vol.2. 2008-05-15T15:10:07-00:00 2001 Microwave Symposium Digest, 2001 IEEE MTT-S International 2 1011 1014 vol.2 circuit design microwave network neural http://www.citeulike.org/user/dcastro/article/2768633 <i>Microwave and Wireless Components Letters, IEEE, Vol. 16, No. 2. (2006), pp. 93-95.</i><br /><br />A new compact defected ground structure (DGS) is proposed for the microstrip line. The structure is compact in microstrip line direction. Here, this DGS is used to design a compact low pass filter (LPF) that is at least 26.3% more compact lengthwise than other reported compact structures and has sharper transition knee. A novel defected ground structure for planar circuits MK Mandal S Sanyal doi:10.1109/LMWC.2005.863192 Microwave and Wireless Components Letters, IEEE, Vol. 16, No. 2. (2006), pp. 93-95. 2008-05-08T06:28:57-00:00 2006 Microwave and Wireless Components Letters, IEEE 16 2 93 95 circuit pbg planar http://www.citeulike.org/user/dcastro/article/2674417 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 55, No. 4. (2007), pp. 729-735.</i><br /><br />This paper describes how circuit and system models are derived for antennas from measurement of the input reflection coefficient. Circuit models are used to optimize the antenna performance and to calculate the radiated power and the transfer function of the antenna. System models are then derived for transmitting and receiving antennas. The most important contribution of this study is to show how microwave structures can be integrated into the simulation of digital communication systems. This enables system designers to predict the effect of the microwave subsystem on the digital signals and calculate the resulting bit error rate System and Circuit Models for Microwave Antennas MI Sobhy B Sanz-Izquierdo JC Batchelor doi:10.1109/TMTT.2007.893675 Microwave Theory and Techniques, IEEE Transactions on, Vol. 55, No. 4. (2007), pp. 729-735. 2008-04-15T17:39:59-00:00 2007 Microwave Theory and Techniques, IEEE Transactions on 55 4 729 735 analysis antenna circuit microwave model simulation http://www.citeulike.org/user/dcastro/article/2648184 <i>The International Journal of Advanced Manufacturing Technology, Vol. 25, No. 3. (1 February 2005), pp. 350-360.</i><br /><br />It is evident that embedded passive components (EPCs) allow packaging substrate miniaturization and have the potential to reduce costs. Moreover, they exhibit superior electrical behaviour with respect to the minimization of parasitic effects. However, as for most emerging technologies, there is no well-established process or method for EPCs that lead to the desired result, but many have been and are still being investigated. This article attempts to review the state of the art of resistor and capacitor EPCs, including an assessment of the pros and cons of the various technologies pursued. In the review, it is found that compared to discrete surface mount devices, EPCs provide (in order of current importance): space reduction of 30% or more, better HF signal integrity and potential cost reduction. Embedded resistors in thin-film technology are, in general, restricted to small resistance values up to a few kΩ. Embedded resistors in ceramic thick-film technology require a high temperature curing process and much care during lamination, but they can be combined with embedded capacitors and exhibit high stability. Whereas embedded resistors in polymer thick-film technology require a low curing temperature and can be combined with capacitors, they exhibit poorer electrical properties and stability. Moreover, tolerances of embedded resistors after manufacturing are exceeded by 15%, independent of the manufacturing technology, which means that laser trimming is required. Embedded capacitors are based mostly on barium-titanite with a dielectric constant of only approximately 20, which limits the capacitance density to a few nF/in 2. Ferroelectric material with a dielectric constant up to 2000 for embedded capacitors has been investigated but not yet established. Besides the traditional screen print technology for the deposition of pastes and inks, the ink-jet technology becomes more promising. Much higher flexibility with respect to material composition, layer thickness and even active components like LEDs have already been produced by ink-jetting. Embedded components in printed circuit boards: a processing technology review W Jillek WKC Yung doi:10.1007/s00170-003-1872-y The International Journal of Advanced Manufacturing Technology, Vol. 25, No. 3. (1 February 2005), pp. 350-360. 2008-04-10T06:55:04-00:00 2005 The International Journal of Advanced Manufacturing Technology 25 3 350 360 circuit component microwave printed http://www.citeulike.org/user/dcastro/article/2499832 <i>Antennas and Wireless Propagation Letters, IEEE, Vol. 5, No. 1. (2006), pp. 559-562.</i><br /><br />Short-circuited ring-patch (SCRP) antennas provide some advantages derived from their property of having as fundamental mode the TM₀₁ mode. This mode has a monopolar radiation pattern with a null in the zenith, in contrast with the radiation patterns of fundamental mode for circular and ring patches (the TM₁₁ mode) that are broadside. The lack of a good characterization of this geometry motivates the present work. In it, an exhaustive study of SCRP antennas via simulations has been performed. The dependence between the fundamental antenna parameters: the internal radius (r), the external radius (R), the permittivity of the substrate (epsi) and its thickness (h); has been studied. Finally, a neural network has been proposed for the analysis and design of these antennas. This has demonstrated to be a useful design tool that provides advantages in computation time with a negligible error in real terms. The simulations have been validated with the manufacturing and test of an antenna Design of Short-Circuited Ring-Patch Antennas Working at $hboxTM_01$ Mode Based on Neural Networks O Quevedo-Teruel E Rajo-Iglesias doi:10.1109/LAWP.2006.889559 Antennas and Wireless Propagation Letters, IEEE, Vol. 5, No. 1. (2006), pp. 559-562. 2008-03-10T09:48:10-00:00 2006 Antennas and Wireless Propagation Letters, IEEE 5 1 559 562 antenna circuit network neural patch ring shorted http://www.citeulike.org/user/dcastro/article/2421336 <i>Solid-State Circuits Conference, 2004. Digest of Technical Papers. ISSCC. 2004 IEEE International (2004), pp. 12-13.</i> SE1 Architectures and Circuits for Ultra Wideband Radio A Chandrakasan T Stetzler R Koch Solid-State Circuits Conference, 2004. Digest of Technical Papers. ISSCC. 2004 IEEE International (2004), pp. 12-13. 2008-02-24T12:55:28-00:00 2004 Solid-State Circuits Conference, 2004. Digest of Technical Papers. ISSCC. 2004 IEEE International 12 13 architecture circuit uwb http://www.citeulike.org/user/dcastro/article/2187934 <i>Antennas and Propagation, IEEE Transactions on [legacy, pre - 1988], Vol. 33, No. 4. (1985), pp. 369-374.</i><br /><br />Input impedance and bandwidth of an annular ring microstrip antenna have been determined by modeling the antenna as a section of radial line loaded with wall admittances. The effect of mutual coupling between the radiating apertures has been taken into account. The theoretically calculated values of input impedance for TM<inf>12</inf>-mode are compared with measurements. The agreement is good. Higher order modes have been found to be present in the vicinity of TM<inf>12</inf>-mode. The reactance due to these modes can be utilized to increase the voltage standing-wave ratio (VSWR) bandwidth of the antenna. Input impedance of annular ring microstrip antenna using circuit theory approach A Bhattacharyya R Garg Antennas and Propagation, IEEE Transactions on [legacy, pre - 1988], Vol. 33, No. 4. (1985), pp. 369-374. 2008-01-02T12:19:07-00:00 1985 Antennas and Propagation, IEEE Transactions on [legacy, pre - 1988] 33 4 369 374 annular antenna circuit impedance microstrip patch ring http://www.citeulike.org/user/dcastro/article/2185979 <i>Applied Electromagnetics and Communications, 2005. ICECom 2005. 18th International Conference on (2005), pp. 1-4.</i><br /><br />Frequency Selective Surfaces's (FSS's) representation with an equivalent circuit composed of lumped elements is very useful in the design stage, where it is desirable to know in a quick way if a FSS is able to give a fixed frequency response. The final aim will be to obtain an equivalent circuit that fits the simulated FSS response with the proposed LC circuit. The method will be validated with a metallic ring on a dielectric substrate. Equivalent Circuit Model Proposal Applied to Frequency Selective Surfaces L Fernandez-Martinez E Garcia D Castro-Galan D Segovia-Vargas Applied Electromagnetics and Communications, 2005. ICECom 2005. 18th International Conference on (2005), pp. 1-4. 2008-01-01T19:35:38-00:00 2005 Applied Electromagnetics and Communications, 2005. ICECom 2005. 18th International Conference on 1 4 circuit fss model tesis http://www.citeulike.org/user/dcastro/article/1992126 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 49, No. 12. (2001), pp. 2322-2330.</i><br /><br />Novel reduced-size lumped-element uniplanar transitions are proposed, using the planar parallel and series inductor-capacitor (LC) circuits to realize the effective open and short circuits, respectively. In this study, various compact lumped-element coplanar waveguide-to-slotline and finite-ground coplanar waveguide-to-coplanar stripline transition structures are developed and carefully examined. Specifically, the performance of proposed basic lumped-element transitions can easily be adjusted through the control of L and C values, while the design of lumped-element Marchand-balun-type transitions may be accomplished by the use of conventional filter synthesis techniques. Simple equivalent-circuit models are also established, from which the passband behavior of the lumped-element transition structures may be characterized Novel lumped-element uniplanar transitions Yo-Shen Lin Chun Chen Microwave Theory and Techniques, IEEE Transactions on, Vol. 49, No. 12. (2001), pp. 2322-2330. 2007-11-27T10:26:14-00:00 2001 Microwave Theory and Techniques, IEEE Transactions on 49 12 2322 2330 circuit lumped microstrip http://www.citeulike.org/user/dcastro/article/1992111 <i>Microwave Symposium Digest, 1998 IEEE MTT-S International, Vol. 3 (1998), pp. 1755-1758 vol.3.</i><br /><br />A general-purpose CAD-oriented circuit model is presented for accurately modeling interdigital capacitor (IDC) in optimized design of low-loss IDC-related microstrip circuits. This equivalent model is formulated as an admittance-based π-network through the use of a so-called “Short-Open Calibration (SOC)” technique for extracting precisely circuit parameters from a fullwave method of moments (MoM). A J-inverter based topology is further developed for explicit characterization of IDC-related coupling characteristics that accounts for frequency dispersion and fringing effect. Extracted model parameters are given for two types of IDC structure and the model accuracy is well validated by our experiments for an IDC-related quasi-lumped bandpass filter A general-purpose circuit model of interdigital capacitor for accurate design of low-loss microstrip circuit Lei Zhu Ke Wu Microwave Symposium Digest, 1998 IEEE MTT-S International, Vol. 3 (1998), pp. 1755-1758 vol.3. 2007-11-27T10:24:18-00:00 1998 Microwave Symposium Digest, 1998 IEEE MTT-S International 3 1755 1758 vol.3 capacitor circuit interdigital microstrip model