Thu, 21 Aug 2008 13:59:53 BST CiteULike: negarehsan's library [17 articles] http://www.citeulike.org/user/negarehsan CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/negarehsan/article/2805700 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 19, No. 2. (1968), pp. 110-116.</i><br /><br />The three-port hybrid considered in this paper is useful both as a power divider and power combiner. In the divider application, power entering the input port is split equally and with zero phase difference between the output ports. All ports are well matched and the output ports are highly isolated. The generalized form of the hyhrid circuit is a T junction followed by a multiplicity of cascaded pairs of TEM line lengths and interconnecting resistors. Due to symmetry, the resistors are decoupled from the input port, but they serve an essential function in providing output-port match and isolation. Each pair of lines and its associated resistor are referred to as a section. The one-section hybrid has been known and widely used. Its usable bandwidth is f/sub 2/ / f/sub 1/ =1.44:1 for VSWR <1.22 and isolation >20 dB. This paper shows that additional sections can provide a large increase in bandwidth. Some of the examples treated are as follows: two sections, f/sub 2/ / f/sub 1/ =2, VSWR <1.11, isolation> 27 dB; four sections, f/sub 2/ / f/sub 1/ =4, VSWR <1.10, isolation >26 dB; and seven sections, f/sub 2/ / f /sub 1/ =10, VSWR <1.21, isolation >19 dB. Exact design formulas are given for two-section hybrids, and approximate design formulas for three or more sections. A Class of Broadband Three-Port TEM-Mode Hybrids SB Cohn Microwave Theory and Techniques, IEEE Transactions on, Vol. 19, No. 2. (1968), pp. 110-116. 2008-05-16T18:34:57-00:00 1968 Microwave Theory and Techniques, IEEE Transactions on 19 2 110 116 divider http://www.citeulike.org/user/negarehsan/article/2805608 <i>Antennas and Propagation, IEEE Transactions on [legacy, pre - 1988], Vol. 35, No. 3. (1987), pp. 327-331.</i><br /><br />A theoretical model and computer simulations of the current on the coaxial collinear (COCO) antenna are presented. Comparisons between numerical results and measurements are made for 24- and 26-element COCO antennas at 50 MHz and for six- and eight-element COCO antennas at 915 MHz. The results show reasonable agreement between first-order theory and measurements. The coaxial collinear antenna: Current distribution from the cylindrical antenna equation T Judasz W Ecklund Ben Balsley Antennas and Propagation, IEEE Transactions on [legacy, pre - 1988], Vol. 35, No. 3. (1987), pp. 327-331. 2008-05-16T17:31:41-00:00 1987 Antennas and Propagation, IEEE Transactions on [legacy, pre - 1988] 35 3 327 331 coco http://www.citeulike.org/user/negarehsan/article/2805599 <i>Antennas and Propagation, IEEE Transactions on, Vol. 37, No. 3. (1989), pp. 289-296.</i><br /><br />An improved theoretical model of the coaxial colinear (COCO) antenna is presented that takes into account different element lengths and power transfers between the antenna and the transmission lines. The antenna equation now contains an exact kernel instead of an approximate kernel and a piecewise constant basis function is used instead of a piecewise linear function, yielding faster results. More points are used for better accuracy and yet faster computations. The linear systems of equations of the theoretical model are solved using a preconditioned conjugate gradient method. Uniform and tapered current distributions are obtained experimentally and theoretically on end-fed coaxial colinear antennas. There is reasonable agreement between theory and measurements. The gains of a few COCO antennas relative to equivalent lengths of half-wave dipoles are given Improved theoretical and experimental models for the coaxial colinear antenna TJ Judasz BB Balsley doi:10.1109/8.18724 Antennas and Propagation, IEEE Transactions on, Vol. 37, No. 3. (1989), pp. 289-296. 2008-05-16T17:20:54-00:00 1989 Antennas and Propagation, IEEE Transactions on 37 3 289 296 coco http://www.citeulike.org/user/negarehsan/article/2805591 <i>Antennas and Propagation, 1995., Ninth International Conference on (Conf. Publ. No. 407) (1995), pp. 410-414 vol.1.</i><br /><br />Coaxial colinear (CoCo) antennas were considered, for decades, just as being wire antennas. However, the concept of the colinear phased array has been introduced by a number of authors. The principle of dual behaviour (transmission line-cylindrical antenna) allowed a better comprehension of these antennas. We give practical results based both on experimentation and simulation. We first show the technique of impedance calculation (which is the basis of bandwidth evaluation). This depends on frequency, array size, and on the physical parameters of the cables. Finally, we investigate the case of CoCo antennas made of elements with different lengths Bandwidth investigation of coaxial colinear antennas B Lagoun L Bertel Antennas and Propagation, 1995., Ninth International Conference on (Conf. Publ. No. 407) (1995), pp. 410-414 vol.1. 2008-05-16T17:18:29-00:00 1995 Antennas and Propagation, 1995., Ninth International Conference on (Conf. Publ. No. 407) 410 414 vol.1 coco http://www.citeulike.org/user/negarehsan/article/2803168 <i>Microwave Symposium, 2007. IEEE/MTT-S International (2007), pp. 1157-1160.</i><br /><br />Miniature hybrid couplers are designed in an air-filled microfabricated rectangular coaxial line technology for operation near 36 GHz. The size of the couplers is less than 2.7 mm by 2.7 mm in area and 420 mum in height. Air-filled copper mu-coaxial cable provides less than 0.3 dB/cm loss at Ka-band. Coaxial-to-CPW probe transitions on the ports provide means to perform 4-port VNA measurements with an external SOLT calibration. After implementing a de-embedding procedure, measurements show return loss and isolation better than 20 dB, with output amplitudes of 3.2 dBplusmn0.1 dB, and output phase differences of 90deg plusmn 2.0deg from 34.5 to 36.5 GHz. The return loss and isolation minima are shifted in frequency as compared to the optimal output amplitude and phase frequency. This frequency difference is 1.5 GHz near 36 GHz with this technology, however branch line couplers using branch-length and reactive tee-junction compensation methods are presented. The improvement is experimentally verified; the frequency differences are 0.5 and 0.2 GHz for the two compensated designs. Balanced Low-Loss Ka-Band ¿-Coaxial Hybrids K Vanhille D Filipovic C Nichols D Fontaine doi:10.1109/MWSYM.2007.380335 Microwave Symposium, 2007. IEEE/MTT-S International (2007), pp. 1157-1160. 2008-05-16T00:23:51-00:00 2007 Microwave Symposium, 2007. IEEE/MTT-S International 1157 1160 rcl http://www.citeulike.org/user/negarehsan/article/2800306 <i>Design Automation Conference, 2003. Proceedings (2003), pp. 73-78.</i><br /><br />In this paper, we discuss the many issues around the system and circuit design of advanced RF front ends for mobile, wireless and consumer RF applications. After an analysis of the application trends, technology choices linked to the different systems solutions is discussed. RF front end application and technology trends PW Hooijmans Design Automation Conference, 2003. Proceedings (2003), pp. 73-78. 2008-05-14T23:46:22-00:00 2003 Design Automation Conference, 2003. Proceedings 73 78 front-end rf http://www.citeulike.org/user/negarehsan/article/2800289 <i>Microwave Conference Proceedings, 1997. APMC '97, 1997 Asia-Pacific (1997), pp. 877-880 vol.2.</i><br /><br />The scattering characteristics of various rectangular coaxial line discontinuities with which a satellite beamforming network (BFN) is built are investigated by the finite difference time domain (FDTD) method. Good agreement has been found between the numerical results and the experimental data, the effectiveness and accuracy of the present approach are thus justified. Some numerical results are given to establish useful guidelines for the design of BFNs FDTD analysis for satellite BFN consisting of rectangular coaxial lines Shanjia Xu Ping Zhou doi:10.1109/APMC.1997.654682 Microwave Conference Proceedings, 1997. APMC '97, 1997 Asia-Pacific (1997), pp. 877-880 vol.2. 2008-05-14T23:34:38-00:00 1997 Microwave Conference Proceedings, 1997. APMC '97, 1997 Asia-Pacific 877 880 vol.2 rcl http://www.citeulike.org/user/negarehsan/article/2747057 <i>Microwave and Optical Technology Letter, Vol. 17, No. 1. (January 1998), pp. 29-37.</i> COMPARISON OF THE BROADBAND PERFORMANCE OF TWO-WAY POWER DIVIDERS AND COMBINERS Gowri Makineni William Joines Microwave and Optical Technology Letter, Vol. 17, No. 1. (January 1998), pp. 29-37. 2008-05-02T20:51:47-00:00 1998 Microwave and Optical Technology Letter 17 1 29 37 divider http://www.citeulike.org/user/negarehsan/article/2743785 <i>IEEE Transactions on Microwave Theory and Techniques (2008)</i><br /><br />This paper addresses microwave circuits for increasing the output voltage of quantum voltage standards. To achieve a 10V programmable Josephson voltage standard, on the order of 250 000 Josephson junctions under uniform Kband microwave-frequency excitation are required. A broadband, lumped-element, Wilkinson power divider centered at 20 GHz was designed and fabricated to uniformly distribute power to arrays of junctions. The measured results from a single Wilkinson divider demonstrate low insertion loss, a 2:1 VSWR bandwidth of 10–26 GHz, and a 10 dB isolation bandwidth of 13–30 GHz. Utilizing the Wilkinson divider, a 16-way, 4-level, binary power divider network intended to excite approximately 18 000 Josephson junctions in each branch is demonstrated in a divider/combiner configuration. This configuration exhibits a 2:1 VSWR from 16.5–24.5 GHz. In the 15–25 GHz band of interest, the maximum insertion loss for the sixteen-way divider network is 1.10 dB, with an average of 0.72 dB, calculated from measurements on the back-to-back divider/combiner configuration. Broadband Integrated Power Dividers for Programmable Josephson Voltage Standards Michael Elsbury Paul Dresselhaus Norman Bergren Charles Burroughs Samuel Benz Zoya Popovi´c IEEE Transactions on Microwave Theory and Techniques (2008) 2008-05-02T00:53:55-00:00 2008 IEEE Transactions on Microwave Theory and Techniques divider http://www.citeulike.org/user/negarehsan/article/2743670 <i>Microwave and Wireless Components Letters, IEEE, Vol. 17, No. 7. (2007), pp. 534-536.</i><br /><br />A 16-46 GHz mixer using broadband balun fabricated in standard 0.18-mum CMOS process is demonstrated. The broadside-coupled balun with wide bandwidth and low insertion loss utilizes the inherent 3D multilayer structure in CMOS process. The mixer exhibits radio frequency bandwidth from 16 to 46 GHz with a conversion loss ranging from 13 plusmn 1.5 dB, and achieves bandwidth over 103% with a compact chip size of 0.24 mm². A 16–46 GHz Mixer Using Broadband Multilayer Balun in 0.18-<formula formulatype="inline"><tex>$mu$</tex></formula>m CMOS Technology Tsung-Yu Yang Hwann-Kaeo Chiou doi:10.1109/LMWC.2007.899320 Microwave and Wireless Components Letters, IEEE, Vol. 17, No. 7. (2007), pp. 534-536. 2008-05-01T23:37:00-00:00 2007 Microwave and Wireless Components Letters, IEEE 17 7 534 536 transformer http://www.citeulike.org/user/negarehsan/article/2743633 <i>Antennas and Propagation Society International Symposium, 2005 IEEE, Vol. 1A (2005), pp. 93-96 Vol. 1A.</i><br /><br />The design of experiments approach has been combined with full wave EM simulations for studying the feasibility of the optimization of a multilayer balun. It was found that it was not possible to obtain satisfactory amplitude and phase balances for the entire frequency band, but the optimization can be performed if less stringent requirements are imposed on the imbalances. The amount of required simulations was a small fraction (more than an order of magnitude) with respect to any other optimization approaches. Design and optimization of 3D multilayer balun architectures using the design of experiments technique LJ Martin D Staiculescu MM Tentzeris Antennas and Propagation Society International Symposium, 2005 IEEE, Vol. 1A (2005), pp. 93-96 Vol. 1A. 2008-05-01T23:18:03-00:00 2005 Antennas and Propagation Society International Symposium, 2005 IEEE 1A 93 96 Vol. 1A transformer http://www.citeulike.org/user/negarehsan/article/2743618 <i>Proceedings of the IEEE, Vol. 69, No. 6. (1981), pp. 728-741.</i><br /><br />The essential theory and practical considerations for the design of low-noise amplifiers are gathered and organized to a uniform presentation. The relevant material is quite simple and straightforward, hopefully bringing within the reach of the interested circuit designer the "art" of low-noise-amplifier design. The design of low-noise amplifiers Y Netzer Proceedings of the IEEE, Vol. 69, No. 6. (1981), pp. 728-741. 2008-05-01T23:06:32-00:00 1981 Proceedings of the IEEE 69 6 728 741 lna http://www.citeulike.org/user/negarehsan/article/2743608 <i>Journal of Physics E: Scientific Instruments, Vol. 14, No. 8. (1981), pp. 939-942.</i><br /><br />Describes the noise characteristics of a magnetic field measurement system which consists of an induction coil detector, a matching input transformer and a sensitive preamplifier. The best noise performance is obtained when the amplifier operates with optimum source resistance. The optimal conditions are obtained by using a transformer to match the source and amplifier resistances. The limited frequency response of the transformer, however, often restricts its application. The methods of designing a broad-band instrumentation transformer are discussed. As an example the transformer construction for a magnetocardiographic measurement system and some measurement results are also presented. Noise reduction using a matching input transformer (magnetic field measurement system) JO Lekkala JAV Malmivuo doi:10.1088/0022-3735/14/8/012 Journal of Physics E: Scientific Instruments, Vol. 14, No. 8. (1981), pp. 939-942. 2008-05-01T22:55:15-00:00 1981 Journal of Physics E: Scientific Instruments 14 8 939 942 transformer http://www.citeulike.org/user/negarehsan/article/2396477 <i>Antennas and Propagation, IEEE Transactions on, Vol. 55, No. 6. (2007), pp. 1804-1809.</i><br /><br />A 95-GHz printed low-loss linear-to-circular polarizer is designed as a component of an active direct-detection millimeter-wave imaging system. The periodic printed grid structure presents different reactances to the TE and TM polarizations, resulting in equal amplitude and phase quadrature upon transmission through four parallel grids. The polarizer is measured in both a Gaussian beam system and a plane wave system, and demonstrates an axial ratio of 0.23 dB, polarization isolation of 38 dB, and transmission loss of 0.3 dB for normal incidence. The quarter-wave plate is characterized up to plusmn35deg off the optical axis, and exhibits an axial ratio better than 1 dB up to plusmn17deg off the optical axis. A <emphasis>W</emphasis>-Band Polarization Converter and Isolator C Dietlein A Luukanen Z Popovic E Grossman doi:10.1109/TAP.2007.898595 Antennas and Propagation, IEEE Transactions on, Vol. 55, No. 6. (2007), pp. 1804-1809. 2008-02-18T21:58:01-00:00 2007 Antennas and Propagation, IEEE Transactions on 55 6 1804 1809 polarizer http://www.citeulike.org/user/negarehsan/article/2743409 <i>Microwave Journal, Vol. 51, No. 2. (19 February 2008), 66.</i> An Enabling New 3D Architecture for Microwave Components and Systems Zoya Popovic Sébastien Rondineau Dejan Filipovic David Sherrer Chris Nicholas Jean-Marc Rollin Ken Vanhille Microwave Journal, Vol. 51, No. 2. (19 February 2008), 66. 2008-05-01T20:42:16-00:00 2008 Microwave Journal 51 2 66 rcl http://www.citeulike.org/user/negarehsan/article/2743391 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 54, No. 6. (2006), pp. 2439-2446.</i><br /><br />Several low-profile 250-/spl mu/m-high Ka-band cavity resonators are demonstrated with resonant frequencies near 26 GHz and unloaded quality (Q) factors greater than 400. The air-filled copper cavity resonators are fabricated on a silicon substrate using a photolithographic process. A microrectangular coaxial transmission-line feed is integrated in the same process. Four resonators with different mechanical support structures are demonstrated. The resonators are designed using the finite-element method and simulation of both the resonant frequency and Q factor agree well with measurements. Quasi-planar high-Q millimeter-wave resonators KJ Vanhille DL Fontaine C Nichols DS Filipovic Z Popovic doi:10.1109/TMTT.2006.875794 Microwave Theory and Techniques, IEEE Transactions on, Vol. 54, No. 6. (2006), pp. 2439-2446. 2008-05-01T20:33:52-00:00 2006 Microwave Theory and Techniques, IEEE Transactions on 54 6 2439 2446 rcl resonator http://www.citeulike.org/user/negarehsan/article/2743371 <i>Microwave Symposium Digest, 2006. IEEE MTT-S International (2006), pp. 1393-1396.</i><br /><br />A miniature non-uniform copper-air rectangular coaxial line with the inner conductor supported by periodic dielectric straps is demonstrated. The overall height of the line is 310mum with the outer conductor cross-section being 250mumtimes250mum. The measured loss is 0.22dB/cm at 26GHz, while the isolation between two parallel lines with a center-to-center separation of 700mum is better than 60dB. Several quasi-planar components are designed and fabricated on the same wafer, and presented here are a branch-line hybrid and a transmission line resonator. The through and coupled port transmissions for the hybrid at 26GHz are -3.25dB and -3.35dB respectively, with phase misbalance below 0.2deg. The transmission line resonator has an unloaded Q-factor of 110 at 25GHz Modeling, Design, Fabrication, and Performance of Rectangular $\upmu$-Coaxial Lines and Components DS Filipovic Z Popovic K Vanhille M Lukic S Rondineau M Buck G Potvin D Fontaine C Nichols D Sherrer S Zhou W Houck D Fleming E Daniel W Wilkins V Sokolov J Evans doi:10.1109/MWSYM.2006.249528 Microwave Symposium Digest, 2006. IEEE MTT-S International (2006), pp. 1393-1396. 2008-05-01T20:12:33-00:00 2006 Microwave Symposium Digest, 2006. IEEE MTT-S International 1393 1396 rcl