CiteULike: dcastro's rf http://www.citeulike.org/user/dcastro/tag/rf CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dcastro/article/2801965 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 51, No. 4. (2003), pp. 1339-1350.</i><br /><br />Neural-network computational modules have recently gained recognition as an unconventional and useful tool for RF and microwave modeling and design. Neural networks can be trained to learn the behavior of passive/active components/circuits. A trained neural network can be used for high-level design, providing fast and accurate answers to the task it has learned. Neural networks are attractive alternatives to conventional methods such as numerical modeling methods, which could be computationally expensive, or analytical methods which could be difficult to obtain for new devices, or empirical modeling solutions whose range and accuracy may be limited. This tutorial describes fundamental concepts in this emerging area aimed at teaching RF/microwave engineers what neural networks are, why they are useful, when they can be used, and how to use them. Neural-network structures and their training methods are described from the RF/microwave designer's perspective. Electromagnetics-based training for passive component models and physics-based training for active device models are illustrated. Circuit design and yield optimization using passive/active neural models are also presented. A multimedia slide presentation along with narrative audio clips is included in the electronic version of this paper. A hyperlink to the NeuroModeler demonstration software is provided to allow readers practice neural-network-based design concepts. Artificial neural networks for RF and microwave design - from theory to practice Qi-Jun Zhang KC Gupta VK Devabhaktuni doi:10.1109/TMTT.2003.809179 Microwave Theory and Techniques, IEEE Transactions on, Vol. 51, No. 4. (2003), pp. 1339-1350. 2008-05-15T15:11:13-00:00 Microwave Theory and Techniques, IEEE Transactions on 51 4 1339 1350 design microwave network neural rf http://www.citeulike.org/user/dcastro/article/2782041 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 50, No. 3. (2002), pp. 814-826.</i><br /><br />The generation of RF/microwave power is required not only in wireless communications, but also in applications such as jamming, imaging, RF heating, and miniature dc/dc converters. Each application has its own unique requirements for frequency, bandwidth, load, power, efficiency, linearity, and cost. RF power is generated by a wide variety of techniques, implementations, and active devices. Power amplifiers are incorporated into transmitters in a similarly wide variety of architectures, including linear, Kalm, envelope tracking, outphasing, and Doherty. Linearity can be improved through techniques such as feedback, feedforward, and predistortion Power amplifiers and transmitters for RF and microwave FH Raab P Asbeck S Cripps PB Kenington ZB Popovic N Pothecary JF Sevic NO Sokal doi:10.1109/22.989965 Microwave Theory and Techniques, IEEE Transactions on, Vol. 50, No. 3. (2002), pp. 814-826. 2008-05-09T23:54:52-00:00 Microwave Theory and Techniques, IEEE Transactions on 50 3 814 826 amplifier microwave power rf transmitter http://www.citeulike.org/user/dcastro/article/2776279 <i>Microwaves, Antennas and Propagation, IEE Proceedings -, Vol. 150, No. 4. (2003), pp. 290-294.</i><br /><br />Two methods for achieving a complete RF front end equipped with its radiator within a single chip package are presented. This packaging technique, which uses a parasitic radiator, provides an alternative solution to problems associated with reduced size electrically small antennas, such as restoration of the antenna gain to 6 dBi and increasing its bandwidth to over 4%. Several parasite configurations have been described and sensitivity of the overall antenna performance to coupling height, parasite dimension, and position with respect to the feed antenna have been assessed. Circular polarisation of such a configuration using a truncated square parasite has also been demonstrated. Novel RF front end antenna package PCT Song PS Hall H Ghafouri-Shiraz doi:10.1049/ip-map:20030414 Microwaves, Antennas and Propagation, IEE Proceedings -, Vol. 150, No. 4. (2003), pp. 290-294. 2008-05-09T16:41:52-00:00 Microwaves, Antennas and Propagation, IEE Proceedings - 150 4 290 294 antenna front-end rf http://www.citeulike.org/user/dcastro/article/2776272 <i>Electron Devices Meeting, 1997. IEDM '97. Technical Digest., International (1997), pp. 301-304.</i><br /><br />The rapid growth of wireless systems at radio frequencies (RF) is driving the need for improved analog circuit and device analysis at gigaHertz frequencies. This includes: low noise front ends, linear amplifiers, mixers, and power amplifiers. Moreover, the parasitic effects of capacitance and inductance, both on- and off-chip, require careful extraction and characterization in support of predictive modeling. While time-domain techniques work well for digital systems, often the spectral and dynamic range requirements for communications systems necessitate accurate analysis of harmonic content with frequency differences of a thousandfold or more. This paper demonstrates the applicability and unique strengths of device-level harmonic balance (HB) in the simulation and physical modeling of RF circuits Device simulation for RF applications RW Dutton B Troyanovsky Z Yu T Arnborg F Rotella G Ma J Sato-Iwanaga doi:10.1109/IEDM.1997.650386 Electron Devices Meeting, 1997. IEDM '97. Technical Digest., International (1997), pp. 301-304. 2008-05-09T16:40:13-00:00 Electron Devices Meeting, 1997. IEDM '97. Technical Digest., International 301 304 rf simulation http://www.citeulike.org/user/dcastro/article/2776271 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 48, No. 6. (2000), pp. 991-999.</i><br /><br />This paper describes how device simulation may be used for the modeling, analysis, and design of radio-frequency (RF) laterally diffused metal-oxide-semiconductor (LDMOS) transistors. Improvements to device analysis needed to meet the requirements of RF devices are discussed. Key modeling regions of the LDMOS device are explored and important physical effects are characterized. The LDMOS model is compared to dc and small-signal ac measurements for calibration purposes. Using the calibrated model, large-signal accuracy is verified using harmonic distortion simulation, and intermodulation analysis. Predictive analysis and a study of the structure's parasitic components are also presented. Load-pull simulation is used to analyze matching network effects to determine the best choices for device impedance matching Modeling, analysis, and design of RF LDMOS devices using harmonic-balance device simulation FM Rotella G Ma Z Yu RW Dutton doi:10.1109/22.904736 Microwave Theory and Techniques, IEEE Transactions on, Vol. 48, No. 6. (2000), pp. 991-999. 2008-05-09T16:40:12-00:00 Microwave Theory and Techniques, IEEE Transactions on 48 6 991 999 analysis design model rf simulation http://www.citeulike.org/user/dcastro/article/2768664 <i>Radio and Wireless Conference, 2003. RAWCON '03. Proceedings (2003), pp. 373-376.</i><br /><br />This paper provides an overview of the current and emerging filter technologies for wireless system applications. Detailed comparisons are given for the various filter technologies used in both base-station and mobile handsets applications. Coaxial, dielectric resonator (DR) and high temperature superconductor (HTS) technologies are addressed for base-station applications while ceramic, multiplayer dielectric, surface acoustic wave (SAW) and film bulk acoustic resonator (FBAR) filters are considered for mobile handsets applications. The current development efforts in each filter technology area are also highlighted. RF filters and diplexers for wireless system applications: state of the art and trends RR Mansour doi:10.1109/RAWCON.2003.1227970 Radio and Wireless Conference, 2003. RAWCON '03. Proceedings (2003), pp. 373-376. 2008-05-08T06:40:36-00:00 Radio and Wireless Conference, 2003. RAWCON '03. Proceedings 373 376 diplexer filter rf wireless http://www.citeulike.org/user/dcastro/article/2768663 <i>Microwave Magazine, IEEE, Vol. 5, No. 4. (2004), pp. 50-65.</i><br /><br />This paper reports on RF-MEMS switchable capacitors, varactors, and ohmic switch technology attribute for both base stations and handsets in realizing frequency-agile RF/wireless systems capable of serving multiple frequency bands. For the handset, this leads to a smaller footprint combined with low power consumption of the RF radio. For the base station the benefit lies in ability for reconfiguration of the air interface, which leads to high logistical savings for infrastructure vendors through a reduction in the number of product variants. Reconfigurable frequency-agile radios are a perfect addition to reconfigurable baseband processing. Both together form the basis of a realistic and reasonable approach to realize software radios. RF MEMS for ubiquitous wireless connectivity. Part II. Application De Los G Fischer HAC Tilmans JTM van Beek doi:10.1109/MMW.2004.1380278(410) 5 Microwave Magazine, IEEE, Vol. 5, No. 4. (2004), pp. 50-65. 2008-05-08T06:40:33-00:00 Microwave Magazine, IEEE 5 4 50 65 rf wireless http://www.citeulike.org/user/dcastro/article/2763869 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 53, No. 10. (2005), pp. 3082-3089.</i><br /><br />The use of direct RF sampling has been explored as a means of designing multifrequency RF front ends. Such front ends will be useful to multifrequency RF applications such as global navigation satellite system receivers that use global positioning system (GPS) L1, L2, and L5 signals and Galileo signals. The design of a practical multifrequency direct RF sampling front end is dependent on having an analog-to-digital converter whose input bandwidth accommodates the highest carrier frequency and whose maximum sampling frequency is more than twice the cumulative bandwidth about the multiple carrier signals. The principle of direct RF sampling is used to alias all frequency bands of interest onto portions of the Nyquist bandwidth that do not overlap. This paper presents a new algorithm that finds the minimum sampling frequency that avoids overlap. This design approach requires a multifrequency bandpass filter for the frequency bands of interest. A prototype front end has been designed, built, and tested. It receives a GPS coarse/acquisition code at the L1 frequency and GPS antispoofing precision code at both L1 and L2. Dual-frequency signals with received carrier-to-noise ratios in excess of 52 dB-Hz have been acquired and tracked using this system. Design and practical implementation of multifrequency RF front ends using direct RF sampling ML Psiaki SP Powell Hee Jung PM Kintner doi:10.1109/TMTT.2005.855127 Microwave Theory and Techniques, IEEE Transactions on, Vol. 53, No. 10. (2005), pp. 3082-3089. 2008-05-07T06:08:30-00:00 Microwave Theory and Techniques, IEEE Transactions on 53 10 3082 3089 design frequency front-end galileo gnss gps multi rf sampling http://www.citeulike.org/user/dcastro/article/2762089 <i>Wireless Communication Technology, 2003. IEEE Topical Conference on (2003), pp. 190-193.</i><br /><br />This paper discusses the recent developments by the author's group in the field of RF front-end technology. This includes standalone RF front-end components such as a self-heterodyne mixer as well as more functional front-end circuitry such as digital and analog beamformers. Advanced and intelligent RF front end technology KMKH Leong T Itoh doi:10.1109/WCT.2003.1321485 Wireless Communication Technology, 2003. IEEE Topical Conference on (2003), pp. 190-193. 2008-05-06T17:15:56-00:00 Wireless Communication Technology, 2003. IEEE Topical Conference on 190 193 receiver rf http://www.citeulike.org/user/dcastro/article/2758007 <i>Telecommunications in Modern Satellite, Cable and Broadcasting Service, 2001. TELSIKS 2001. 5th International Conference on, Vol. 1 (2001), pp. 3-9 vol.1.</i><br /><br />Several developments in RF front end technology based upon the active antenna concept are presented. RF front ends utilizing active antenna concepts have shown improvements in such areas as power added efficiency, compactness, low noise figure, and increased functionality. These improvements are illustrated with a Class F power amplifier transmitter with an integrated circular patch antenna, a circularly polarized patch antenna with integrated LNAs, a 60 GHz quasi-optics self oscillating mixer, and two designs implementing the recently developed broadband quasi-Yagi antenna Recent developments in RF front ends based upon active antenna concepts JD Fredrick T Itoh doi:10.1109/TELSKS.2001.954838 Telecommunications in Modern Satellite, Cable and Broadcasting Service, 2001. TELSIKS 2001. 5th International Conference on, Vol. 1 (2001), pp. 3-9 vol.1. 2008-05-05T14:11:19-00:00 Telecommunications in Modern Satellite, Cable and Broadcasting Service, 2001. TELSIKS 2001. 5th International Conference on 1 3 9 vol.1 active antenna rf http://www.citeulike.org/user/dcastro/article/2758006 <i>Antennas and Propagation Society International Symposium, 1999. IEEE, Vol. 2 (1999), pp. 876-879 vol.2.</i><br /><br />Active integrated antennas (AIA) provide a new paradigm for designing modern microwave and millimeter-wave wireless systems. Benefits of this technique include compactness, reduced losses and weight, low profile and multiple functionality. We describe here three novel AIA architectures that have recently been developed, including a tuned-harmonic class F transmitter front-end, power combining with a dual-feed AIA push-pull power amplifier and a novel 2D retrodirective array Active integrated antennas for new RF architectures WR Deal Y Qian T Itoh doi:10.1109/APS.1999.789452 Antennas and Propagation Society International Symposium, 1999. IEEE, Vol. 2 (1999), pp. 876-879 vol.2. 2008-05-05T14:10:55-00:00 Antennas and Propagation Society International Symposium, 1999. IEEE 2 876 879 vol.2 active antenna integrated rf http://www.citeulike.org/user/dcastro/article/2758004 <i>Microwaves, Radar and Wireless Communications. 2000. MIKON-2000. 13th International Conference on, Vol. 3 (2000), pp. 17-22 vol.3.</i><br /><br />This paper provides an overview of numerous recent advancements in RF front end technology. Various techniques for designing novel front-end technology are outlined. Examples of the application of the active integrated antenna design approach are given for both the high-power transmitter and low-noise receiver modes. In addition, several architectures implementing novel mixer designs are presented to achieve baseband receivers and retrodirective arrays New RF front end technologies T Itoh doi:10.1109/MIKON.2000.914040 Microwaves, Radar and Wireless Communications. 2000. MIKON-2000. 13th International Conference on, Vol. 3 (2000), pp. 17-22 vol.3. 2008-05-05T14:10:04-00:00 Microwaves, Radar and Wireless Communications. 2000. MIKON-2000. 13th International Conference on 3 17 22 vol.3 active antenna microwave rf http://www.citeulike.org/user/dcastro/article/2648101 <i>Selected Areas in Communications, IEEE Journal on, Vol. 5, No. 2. (1987), pp. 286-298.</i><br /><br />To accurately predict the performance of broadcast teletext systems, one must know the characteristics of typical over-the-air broadcast television channels. Consequently, ensembles of typical complex impulse responses of broadcast teletext channels in the VHF and UHF frequency ranges are required for computer performance simulations. To circumvent the lack of comprehensive measured channel data, a theoretical multipath propagation model for suburban and urban environments was developed to gain insight into the nature of typical television multipath channels. In this model, both the direct and scatter paths consist of a line-of-sight and ground-reflected component. The basis of the propagation model is an expression for the ratio of the scattered path to direct path field strength caused by vertically oriented dielectric slabs of specified thickness, height, and width. The reflector location, orientation, width, height, and thickness are randomized for each Monte Carlo simulation cycle. A scatter table of relative amplitude versus multipath delay is maintained for subsequent analysis and formation of typical multipath channel impulse responses. A perceived desired-to-undesired ratio (PDUR), which is essentially a signal-to-clutter ratio, is computed to eliminate channels of unacceptable video quality, as these would be of no interest to the teletext application. A modification to account for near-field scattering is described. Finally, mobile channel applications are discussed. A Multipath RF Propagation Model for Computer Simulation of Complex Impulse Responses of Broadcast Teletext Channels M Sablatash R Tiedemann K Moreland Selected Areas in Communications, IEEE Journal on, Vol. 5, No. 2. (1987), pp. 286-298. 2008-04-10T06:22:13-00:00 Selected Areas in Communications, IEEE Journal on 5 2 286 298 channel model multipath propagation rf simulation http://www.citeulike.org/user/dcastro/article/2072429 <i>Proceedings of the IRE, Vol. 38, No. 2. (1950), pp. 148-151.</i><br /><br />A vector parameter is defined which represents a generalization of the effective length of an antenna to include a specification of the polarization of the field radiated by the antenna. It is shown that the parameter so defined is also useful in calculating the voltage at the terminals of the antenna when it is used to receive plane waves of arbitrary (elliptical) polarization. The Transmission and Reception of Elliptically Polarized Waves G Sinclair Proceedings of the IRE, Vol. 38, No. 2. (1950), pp. 148-151. 2007-12-07T10:22:33-00:00 Proceedings of the IRE 38 2 148 151 rf transmission http://www.citeulike.org/user/dcastro/article/2072413 <i>Microwave Conference, 2005 European, Vol. 1 (2005), 4 pp..</i><br /><br />In the present work, a design procedure for multiplexer development has been described. This procedure allows to reduce development time by using of some local optimizations instead of one global. LTCC (low-temperature co-fired ceramic) triplexer for WiMax (IEEE 802.16e) applications, designed in accordance with described procedure, has been presented. The measured results agree well with the simulation. LTCC triplexer for WiMax applications D Orlenko G Sevskiy T Kerssenbrock P Heide Microwave Conference, 2005 European, Vol. 1 (2005), 4 pp.. 2007-12-07T10:18:27-00:00 Microwave Conference, 2005 European 1 4 pp. component rf wimax http://www.citeulike.org/user/dcastro/article/2067715 <i>Antennas and Propagation Society International Symposium, 2005 IEEE, Vol. 1A (2005), pp. 656-659 Vol. 1A.</i><br /><br />A super compact multilayer broadband left-handed metamaterial medium for RF/MMIC applications is proposed and demonstrated by the full wave simulation and equivalent circuit analysis. Here we propose to employ multilayer technology to realize left-handedness. The unit cell of the multilayer structure is a thousand times smaller than that of the microstrip structure to achieve the same series capacitance. The left handedness of the novel structure extends from 2.1GHz to 28.2GHz. performing in much wider bandwidth than those reported so far. The compactness and broad left-handed operating bandwidth make the proposed left-handed metamaterial be well incorporated with RF/MMIC applications. A super compact multilayer broadband left-handed metamaterials for RF/MMIC applications Wei Tong ZR Hu Antennas and Propagation Society International Symposium, 2005 IEEE, Vol. 1A (2005), pp. 656-659 Vol. 1A. 2007-12-06T17:01:28-00:00 Antennas and Propagation Society International Symposium, 2005 IEEE 1A 656 659 Vol. 1A broadband compact lh metamaterial rf http://www.citeulike.org/user/dcastro/article/771617 <i>Radio and Wireless Symposium, 2006 IEEE (2006), pp. 31-34.</i><br /><br />A zero-IF, 4.9-5.95 GHz, 2.3-2.5 GHz, transceiver is fabricated on a 0.18 /spl mu/m CMOS process. By using a fractional-N synthesizer, an integrated phase error of 0.6/spl deg/ (0.7/spl deg/) at 5 GHz (2.4 GHz) is achieved, while supporting fine frequency resolution. Digital calibration eliminates I/Q mismatch and achieves accurately matched baseband filters. The transceiver is compliant to 802.11a/b/g, while programmable bandwidth filters and an EVM of -35 dB in both transmit and receive, make it suitable for applications based on 802.16d/e. A dual-band 4.9-5.95 GHz, 2.3-2.5 GHz, 0.18 /spl mu/m CMOS transceiver for 802.11 a/b/g-802.16d/e I Vassiliou K Vavelidis N Haralabidis S Kavadias S Bouras G Kamoulakos C Kapnistis Y Kokolakis A Kyranas E Metaxakis S Plevridis P Merakos K Tsilipanos Radio and Wireless Symposium, 2006 IEEE (2006), pp. 31-34. 2006-07-24T16:24:44-00:00 Radio and Wireless Symposium, 2006 IEEE 31 34 80211 80216 dual-band rf transceiver