Wed, 09 Jul 2008 13:27:04 BST CiteULike: dcastros loss http://www.citeulike.org/user/dcastro/tag/loss CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dcastro/article/2941949 <i>Journal of Zhejiang University - Science A, Vol. 7, No. 1. (23 January 2006), pp. 5-23.</i><br /><br />Abstract  In this paper, we summarize some recent activities in the field of metamaterial research at the National University of Singapore (NUS). Integral equations are applied for electromagnetic modelling of supernatural materials. Some special characteristics of the metamaterials are shown. Moreover, quasi-static Lorentz theory and numerical method (i.e., the method of moments for solving the electric field integral equation) and the transmission line theory are both presented to obtain the effective constitutive relations of metamaterials, respectively. Finally, feasibility of fabricating metamaterials based on analysis of equivalent transmission line model in the microwave spectrum and even higher is also shown and correspondingly some broad-bandwidth and low-loss metamaterial structures are designed and synthesized. Broad-bandwidth and low-loss metamaterials: Theory, design and realization Le-Wei Li Hai-Ying Yao Qun Wu Zhi-Ning Chen doi:10.1631/jzus.2006.A0005 Journal of Zhejiang University - Science A, Vol. 7, No. 1. (23 January 2006), pp. 5-23. 2008-06-29T18:25:25-00:00 2006 Journal of Zhejiang University - Science A 7 1 5 23 broadband loss low metamaterial http://www.citeulike.org/user/dcastro/article/2782029 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 51, No. 4. (2003), pp. 1241-1246.</i><br /><br />This paper presents a new compact, low insertion-loss, sharp-rejection, and wide-band microstrip bandpass filter. A bandstop filter is introduced that uses a ring resonator with direct-connected orthogonal feed lines. A new bandpass filter based on the bandstop filter uses two tuning stubs to construct a wide-band passband with two sharp stopbands. Without coupling gaps between feed lines and rings, there are no mismatch and radiation losses between them and, therefore, the new filters show low insertion loss. In addition, a dual-mode characteristic is used to increase the stopband bandwidth of the new filters. A simple transmission-line model used to calculate the frequency responses of the filters shows good agreement with measurements. The filter using three cascaded rings has 3-dB fractional bandwidth of 49.3%, an insertion loss of better than 1.6 dB in the passband, a return loss of larger than 13 dB from 4.58 to 7.3 GHz, and two rejections of greater than 40 dB within 2.75-4.02 and 7.73-9.08 GHz. The high-performance, compact-size, and low-cost filter was designed for reducing the interference in full duplex systems in satellite communications. Compact, low insertion-loss, sharp-rejection, and wide-band microstrip bandpass filters Lung-Hwa Hsieh Kai Chang doi:10.1109/TMTT.2003.809643 Microwave Theory and Techniques, IEEE Transactions on, Vol. 51, No. 4. (2003), pp. 1241-1246. 2008-05-09T23:50:43-00:00 2003 Microwave Theory and Techniques, IEEE Transactions on 51 4 1241 1246 bandpass compact filter loss low microstrip http://www.citeulike.org/user/dcastro/article/2768625 <i>Microwave Theory and Techniques, IEEE Transactions on, Vol. 49, No. 10. (2001), pp. 1818-1820.</i><br /><br />This paper introduces a three-port microstrip multifrequency diplexer used in a phased-array transceiver system that employs band-stop filters with open-circuited stubs for band selection and separation. The diplexer is designed to take 10, 12, 19, and 21 GHz into port 1 and to separate 10 and 19 GHz to port 2 and 12 and 21 GHz to part 3 with minimal dispersion. The insertion loss for each frequency varies from 0.4 to 3.4 db and the return loss is better than 10 dB. The isolation between channels at the four frequencies is greater than 50 dB. Each passband created between adjacent stopbands has a bandwidth over 1 GHz. The microstrip diplexer is designed using periodic stubs that collectively have the advantages of low insertion loss, high isolation and rejection, wide-band performance on each channel, and easy fabrication. This type of diplexer has many applications in multifrequency transceivers for communication systems Wide-band low-loss high-isolation microstrip periodic-stub diplexer for multiple-frequency applications B Strassner K Chang doi:10.1109/22.954789 Microwave Theory and Techniques, IEEE Transactions on, Vol. 49, No. 10. (2001), pp. 1818-1820. 2008-05-08T06:28:18-00:00 2001 Microwave Theory and Techniques, IEEE Transactions on 49 10 1818 1820 diplexer frequency high isolation loss low microstrip multiple wideband http://www.citeulike.org/user/dcastro/article/2672813 <i>Vehicular Technology, IEEE Transactions on, Vol. 26, No. 4. (1977), pp. 340-344.</i><br /><br />Performance of some mobile radio systems is limited both by multipath delay spread and average path loss. This paper presents data indicating a low correlation between delay spread and path loss at 910 MHz for 100 small areas within a 2 × 2 ½-km region. Some small areas with low path loss have large delay spread. The region extends from 1.5 to 3.5 km from a base station on a 120-m high building in New York City. The region is representative of heavily built-up downtown districts of many large U.S. cities. Multipath delay spread and path loss correlation for 910-MHz urban mobile radio propagation DC Cox Vehicular Technology, IEEE Transactions on, Vol. 26, No. 4. (1977), pp. 340-344. 2008-04-15T10:34:36-00:00 1977 Vehicular Technology, IEEE Transactions on 26 4 340 344 correlation delay loss mobile multipath propagation radio urban