Sun, 27 Jul 2008 07:40:58 BST CiteULike: dcastro's Deal http://www.citeulike.org/user/dcastro/author/Deal CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dcastro/article/2801477 <i>Antennas and Propagation Society International Symposium, 1998. IEEE, Vol. 2 (1998), pp. 656-659 vol.2.</i><br /><br />A periodically loaded substrate is employed to reduce excitation of surface waves by a patch antenna. The computed dispersion diagram of the substrates shows that surface wave propagation is forbidden along specific directions. By properly orienting the patch antenna on the substrate, this can result in good improvement of antenna performance. In agreement with the expected result, the measured radiation pattern shows a 10 dB reduction in the side lobes associated with power launched from surface waves Radiation characteristics of a patch antenna on a thin PBG substrate R Coccioli WR Deal T Itoh doi:10.1109/APS.1998.702023 Antennas and Propagation Society International Symposium, 1998. IEEE, Vol. 2 (1998), pp. 656-659 vol.2. 2008-05-15T12:19:03-00:00 1998 Antennas and Propagation Society International Symposium, 1998. IEEE 2 656 659 vol.2 antenna patch pbg http://www.citeulike.org/user/dcastro/article/2801463 <i>Electronics Letters, Vol. 34, No. 23. (1998), pp. 2194-2196.</i><br /><br />A compact and uniplanar antenna with broadband characteristics is presented. The novel Yagi-like printed dipole array antenna is fed by a microstrip-to-coplanar strip transition, and uses the truncated microstrip ground plane as its reflecting element. An X-band prototype measures a bandwidth of 17%. With 6.5 dB gain, 18 dB front-to-back ratio, and lower than -15 dB cross-polarisation level at 10 GHz Microstrip-fed quasi-Yagi antenna with broadband characteristics Y Qian WR Deal N Kaneda T Itoh Electronics Letters, Vol. 34, No. 23. (1998), pp. 2194-2196. 2008-05-15T12:14:41-00:00 1998 Electronics Letters 34 23 2194 2196 antenna broadband microstrip http://www.citeulike.org/user/dcastro/article/2801456 <i>Microwave Symposium Digest, 1998 IEEE MTT-S International, Vol. 2 (1998), pp. 1135-1138 vol.2.</i><br /><br />The global time-domain nonlinear analysis of microwave FET oscillators and self-oscillating mixers using the extended FDTD technique is presented. Employing the concept of equivalent current/voltage sources, the device-wave interaction is characterized and incorporated into the FDTD time-stepping algorithm. Consequently, investigation of highly nonlinear phenomena, such as injection locking and intermodulation, can be accomplished by utilizing a large-signal device circuit model. Theoretical results are validated by experiments Global time-domain full-wave analysis of microwave FET oscillators and self-oscillating mixers Min Chen WR Deal B Houshmand T Itoh doi:10.1109/MWSYM.1998.705194 Microwave Symposium Digest, 1998 IEEE MTT-S International, Vol. 2 (1998), pp. 1135-1138 vol.2. 2008-05-15T12:12:47-00:00 1998 Microwave Symposium Digest, 1998 IEEE MTT-S International 2 1135 1138 vol.2 fet microwave mixer oscillator http://www.citeulike.org/user/dcastro/article/2801376 <i>Microwave Symposium Digest, 1998 IEEE MTT-S International, Vol. 3 (1998), pp. 1383-1386 vol.3.</i><br /><br />In this work, a beam-scanning array for antenna remoting via an optical link is presented. Optical control over the main beam is accomplished through the use of a photosensitive resonator. Experimental data shows a total scan angle up to 36° can be achieved with this optical technique All-optically controlled beam-scanning array for antenna remoting applications WR Deal T Jung MC Wu T Itoh doi:10.1109/MWSYM.1998.700632 Microwave Symposium Digest, 1998 IEEE MTT-S International, Vol. 3 (1998), pp. 1383-1386 vol.3. 2008-05-15T11:34:52-00:00 1998 Microwave Symposium Digest, 1998 IEEE MTT-S International 3 1383 1386 vol.3 antenna array beam optical http://www.citeulike.org/user/dcastro/article/2801370 <i>Antennas and Propagation Society International Symposium, 1999. IEEE, Vol. 2 (1999), pp. 924-927 vol.2.</i><br /><br />We report for the first time a planar quasi-Yagi antenna printed on a single layer of high dielectric constant substrate (Durold, &epsiv; _r=10.2) which measures 48% bandwidth (VSWR<2). The antenna radiates an end-fire beam, with a front-to-back ratio >15 dB and cross-polarization level below -12 dB across the entire frequency band. A very low mutual coupling level of below -22 dB has been measured for a two-element array with λ₀/2 separation A uniplanar quasi-Yagi antenna with wide bandwidth and low mutual coupling characteristics Yongxi Qian WR Deal N Kaneda T Itoh doi:10.1109/APS.1999.789463 Antennas and Propagation Society International Symposium, 1999. IEEE, Vol. 2 (1999), pp. 924-927 vol.2. 2008-05-15T11:31:37-00:00 1999 Antennas and Propagation Society International Symposium, 1999. IEEE 2 924 927 vol.2 antenna coupling low planar wideband http://www.citeulike.org/user/dcastro/article/2801361 <i>Microwave Conference, 1999 Asia Pacific, Vol. 1 (1999), pp. 142-145 vol.1.</i><br /><br />A novel printed antenna with broadband circular polarization (CP) characteristics is presented. The antenna design is based on a recently developed uniplanar quasi-Yagi. The antenna measures VSWR<2 and AR<3 dB in the frequency range from 3.40 to 6.34 GHz (60.4%). The bandwidth is more than twice that of the best planar CP antenna to our knowledge. The measured dual-linear pattern at 5 GHz shows that the antenna has excellent CP performance, with its AR below 6 dB over a wide range of scan angles (±80°) from the mainbeam direction A novel printed antenna with broadband circular polarization Yongxi Qian WR Deal J Sor T Itoh doi:10.1109/APMC.1999.828070 Microwave Conference, 1999 Asia Pacific, Vol. 1 (1999), pp. 142-145 vol.1. 2008-05-15T11:29:01-00:00 1999 Microwave Conference, 1999 Asia Pacific 1 142 145 vol.1 antenna broadband circular polarisation printed http://www.citeulike.org/user/dcastro/article/2801360 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 48, No. 6. (2000), pp. 910-918.</i><br /><br />In this paper, a novel broadband planar antenna based on the classic Yagi-Uda dipole antenna is presented, and its usefulness as an array antenna is explored. This “quasi-Yagi” antenna is realized on a high dielectric-constant substrate, and is completely compatible with microstrip circuitry and solid-state devices. This antenna achieves a measured 48% frequency bandwidth for voltage standing-wave ratio <2, better than a 12-dB front-to-back ratio, smaller than -15 dB cross polarization, and 3-5-dBi absolute gain. Mutual coupling of the antenna in an array environment is investigated. Finally, three simple arrays are presented, demonstrating the usefulness of the antenna as an array element. This novel antenna should find wide application in wireless communication systems, power combining, phased arrays, and active arrays, as well as millimeter-wave imaging arrays A new quasi-Yagi antenna for planar active antenna arrays WR Deal N Kaneda J Sor Y Qian T Itoh doi:10.1109/22.846717 Microwave Theory and Techniques, IEEE Transactions on, Vol. 48, No. 6. (2000), pp. 910-918. 2008-05-15T11:28:58-00:00 2000 Microwave Theory and Techniques, IEEE Transactions on 48 6 910 918 active antenna array planar http://www.citeulike.org/user/dcastro/article/2801356 <i>Radio and Wireless Conference, 1999. RAWCON 99. 1999 IEEE (1999), pp. 231-234.</i><br /><br />An active array with a quasi-Yagi antenna element is presented. The array has a bandwidth of 60% (VSWR <2) and a fan-beam pattern. The gain of the active array is measured to range from 22-25 dB from 8-11.7 GHz. The single layer compact design makes this array antenna ideal as a building block in larger 2-D arrays A broadband uniplanar quasi-Yagi active array for power combining WR Deal J Sor Y Qian T Itoh doi:10.1109/RAWCON.1999.810972 Radio and Wireless Conference, 1999. RAWCON 99. 1999 IEEE (1999), pp. 231-234. 2008-05-15T11:27:42-00:00 1999 Radio and Wireless Conference, 1999. RAWCON 99. 1999 IEEE 231 234 active array broadband combining power http://www.citeulike.org/user/dcastro/article/2782065 <i>Microwave Conference, 2000 Asia-Pacific (2000), pp. 888-894.</i><br /><br />In this paper, we present two novel design architectures that utilizing either a periodic structure or an active integrated antenna (AIA) for harmonic tuning in transmitter front-end designs. These techniques promise to significantly improve the power amplifier efficiency, reduce losses and weight, as well as maintaining good linearity requirements of advanced wireless communication systems. We will illustrate these two concepts through several design examples that have been developed recently, including a power amplifier integrated with novel PBG ground plane for harmonic tuning and four push-pull PA design examples, where the AIA concept is implemented to allow antenna to serve as a power combiner, a harmonic tuning load, in addition to its original functionality as a radiating element High efficiency transmitter front-ends integrated with planar antennas and PBG CY Hang WR Deal Yongxi Qian T Itoh doi:10.1109/APMC.2000.925972 Microwave Conference, 2000 Asia-Pacific (2000), pp. 888-894. 2008-05-10T00:03:23-00:00 2000 Microwave Conference, 2000 Asia-Pacific 888 894 antenna efficiency front-end high integrated pbg planar transmitter http://www.citeulike.org/user/dcastro/article/2768746 <i>Antennas and Propagation, IEEE Transactions on, Vol. 50, No. 8. (2002), pp. 1158-1160.</i><br /><br />A novel broadband planar antenna based on the classic Yagi-Uda dipole array is presented. This "quasi-Yagi" antenna achieves a measured 48% bandwidth for VSWR <2, better than 12 dB front-to-back ratio, smaller than -15 dB cross polarization, 3-5 dB absolute gain and a nominal efficiency of 93% across the operating bandwidth. Finite-difference time-domain simulation is used for optimization of the antenna and the results agree very well with measurements. Additionally, a gain-enhanced design is presented, where higher gain has been achieved at the cost of reduced bandwidth. These quasi-Yagi antennas are realized on a high dielectric constant substrate and are completely compatible with microstrip circuitry and solid-state devices. The excellent radiation properties of this antenna make it ideal as either a stand-alone antenna with a broad pattern or as an array element. The antenna should find wide applications in wireless communication systems, power combining, phased arrays and active arrays, as well as millimeter-wave imaging arrays. A broadband planar quasi-Yagi antenna N Kaneda WR Deal Yongxi Qian R Waterhouse T Itoh doi:10.1109/TAP.2002.801299 Antennas and Propagation, IEEE Transactions on, Vol. 50, No. 8. (2002), pp. 1158-1160. 2008-05-08T07:28:52-00:00 2002 Antennas and Propagation, IEEE Transactions on 50 8 1158 1160 antenna broadband planar http://www.citeulike.org/user/dcastro/article/2759137 <i>Microwave Symposium Digest., 2000 IEEE MTT-S International, Vol. 1 (2000), pp. 533-536 vol.1.</i><br /><br />In this paper, a C-band active integrated antenna push-pull power amplifier is presented. The circuit utilizes a uniplanar quasi-Yagi antenna with corrugated ground plane for both out-of-phase power combining and second harmonic tuning. This novel structure results in a compact and high-efficiency power amplifier design with automatic second harmonic suppression. At an operating frequency of 4.15 GHz, a maximum measured PAE of 60.9% at an output power of 28.2 dBm has been achieved Push-pull power amplifier integrated with quasi-Yagi antenna for power combining and harmonic tuning CY Hang WR Deal Y Qian T Itoh doi:10.1109/MWSYM.2000.861110 Microwave Symposium Digest., 2000 IEEE MTT-S International, Vol. 1 (2000), pp. 533-536 vol.1. 2008-05-05T20:24:31-00:00 2000 Microwave Symposium Digest., 2000 IEEE MTT-S International 1 533 536 vol.1 active amplifier antenna integrated power 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 1999 Antennas and Propagation Society International Symposium, 1999. IEEE 2 876 879 vol.2 active antenna integrated rf http://www.citeulike.org/user/dcastro/article/2755629 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 49, No. 6. (2001), pp. 1155-1161.</i><br /><br />This paper presents a C-band push-pull power amplifier integrated with a modified uniplanar quasi-Yagi antenna. In this circuit, corrugation is added to the truncated ground plane of the antenna so that it can be used for both out-of-phase power combining and second harmonic tuning. By using the active integrated antenna concept, this novel circuit eliminates the usage of an ordinary 180° hybrid at the power-amplifier output stage, therefore eliminating the losses associated with the hybrid, resulting in a compact and high-efficiency power-amplifier design with intrinsic second harmonic suppression. At an operating frequency of 4.15 GHz, a maximum measured power-added efficiency (PAE) of 60.9% at an output power of 28.2 dBm has been achieved. The measured PAE is above 50% over a 260-MHz bandwidth. Additionally, the second harmonic radiation is found to be 30 dB below the fundamental in both E- and H-planes. When the circuit is subjected to a two-tone test, the measured third-order intercept point is 37 dBm, about 10 dB above the P_{1 dB} point High-efficiency push-pull power amplifier integrated with quasi-Yagi antenna CY Hang WR Deal Yongxi Qian T Itoh doi:10.1109/22.925510 Microwave Theory and Techniques, IEEE Transactions on, Vol. 49, No. 6. (2001), pp. 1155-1161. 2008-05-05T08:04:57-00:00 2001 Microwave Theory and Techniques, IEEE Transactions on 49 6 1155 1161 active amplifier antenna efficiency high integrated power