{"title":"Project of antenna arrays with random parameters","authors":"Wamberto J. L. Queiroz, M. Alencar","doi":"10.1109/IMOC.2003.1244827","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244827","url":null,"abstract":"This paper presents a new way of projecting linear arrays structures using random excitation coefficients and random spacing between sensors. The results obtained show that these configurations can produce good radiation patterns in terms of side lobes level and other project specifications. Depending upon chosen parameters the radiation pattern can be optimized as compared to the one obtained using binomial coefficients. It can be as good as the patterns obtained using the Dolph-Tschebyscheff algorithm. This method can be used in order to get a smoother radiation pattern and can be useful to control the radiation pattern in response to user mobility. Another advantage is related to the numerical processing involved in the computation of excitation coefficients. They are chosen randomly from a convenient set, while in the other cases they are computed in real time and depend upon antenna dimensions, a task which can be computer intensive.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127654118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tao Yu, Huafeng Zhao, Lin Xue, Shan Huang, K. Zhou
{"title":"Fabry-Perot filter frequency stabilization control for multiple ITU wavelengths reference","authors":"Tao Yu, Huafeng Zhao, Lin Xue, Shan Huang, K. Zhou","doi":"10.1109/IMOC.2003.1244873","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244873","url":null,"abstract":"As the space between the channels of dense wavelength division multiplexing (DWDM) systems becomes narrower, a variety of equipment is needed to have more precise frequencies and greater frequency stability. The research of frequency standards in the 1.5 /spl mu/m region has become a hot topic in the optical communication area. In this paper, the frequency locking method of semiconductor lasers has been analyzed. In order to provide multiple ITU wavelength references for DWDM applications, a novel Fabry-Perot (F-P) filter frequency stabilization control system is presented. A frequency stabilized fiber Bragg grating (FBG) external cavity laser diode (ECLD) using acetylene (C/sub 2/H/sub 2/) has been fabricated. With the lock-in amplifier and the FBG ECLD stabilized by absorption of C/sub 2/H/sub 2/ as the reference, one transmission peak of Fabry-Perot inserted in the external cavity is locked at a 1530.3 nm peak of C/sub 2/H/sub 2/ to keep all of its transmission peaks stable, such that the F-P filter with 100 GHz spacing generates a stable and precise wavelength comb, and provides a set of ITU standards at the 1.55 /spl mu/m wavelength band. Our setup is useful for frequency lock-in or frequency measurement and calibration and is promising for DWDM communication systems.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124208843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A novel RF vertical MOSFET for pulsed applications [UHF amplifier]","authors":"P. H. Wilson","doi":"10.1109/IMOC.2003.1244837","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244837","url":null,"abstract":"This paper discusses the results of a high breakdown voltage vertical DMOS RF amplifier that employs power trench technology/spl trade/ to achieve high pulse RF peak power. The RF device can achieve a power of 80 W at an operating voltage of 26 V and a 5% duty cycle.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121990084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A theoretical analysis of optical phase-lock loop acquisition and tracking for WDM receiver applications","authors":"M. S. Gonçalves, A. Bordonalli","doi":"10.1109/IMOC.2003.1244867","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244867","url":null,"abstract":"The acquisition and tracking characteristics of optical phase-lock loops for WDM receiver applications are theoretically analyzed in this work. As the locking bandwidth is controlled by a convenient design of the feedback loop, an optical WDM channel, whose frequency lies within the receiver locking range, can induce the locking of a slave semiconductor laser and be properly detected without the need for optical filters. Other carriers are discarded by the loop electronics bandwidth. The receiver modeling takes into account the loop feedback effect over the slave laser rate equations, allowing a time-dependent analysis of the locking process. Once locking is acquired, the model also allows the analysis of the loop tracking during WDM channel frequency modulation.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"458 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126001461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Guterrez-Martinez, A. García-Juárez, J. A. Torres‐Fórtiz, J. Meza-Perez
{"title":"Photonic generation of microwave carriers for high speed radio-fiber telecommunications","authors":"C. Guterrez-Martinez, A. García-Juárez, J. A. Torres‐Fórtiz, J. Meza-Perez","doi":"10.1109/IMOC.2003.1244871","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244871","url":null,"abstract":"In this paper, we report the generation of microwaves by mixing two optical signals coming from two different lasers one of them being multi-longitudinal. The generated microwaves, in a range of 1-25 GHz, can be used as information carriers which can be modulated and transmitted through long distance radio-fiber links.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"131 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124706973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Georges Amvame-Nze, Antonio José Martins Soares, Franklin da Costa Silva
{"title":"Analysis and tests of the new cylindrical dipole antenna structure with a bazooka balun","authors":"Georges Amvame-Nze, Antonio José Martins Soares, Franklin da Costa Silva","doi":"10.1109/IMOC.2003.1244888","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244888","url":null,"abstract":"In this paper, a new cylindrical dipole antenna structure is analyzed using the finite-difference time-domain (FDTD) method developed for solving Maxwell's equations with the body of revolution (BOR) technique. A two-dimensional finite difference lattice is used to study the efficiency of a bazooka balun type, connected at the bottom of the cylindrical dipole antenna. A good agreement of the experimental and theoretical result from this new structure is shown, with the FDTD calculation design at a center frequency of 800 MHz. We conclude that the result demonstrated in this paper shows the great efficiency of the FDTD algorithm for such complex structures analysis.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131080405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"160 Gbit/s soliton transmission in the S and C bands","authors":"L. Coelho, C. Bastos-Filho, J. Martins-Filho","doi":"10.1109/IMOC.2003.1244866","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244866","url":null,"abstract":"We present for the first time results of soliton transmission in the S-band. We performed computer simulations of single channel solitonic communication systems at 80 Gbit/s and 160 Gbit/s, in the Quasi-Adiabatic regime, in the S and C bands. For the S band we employ non-zero dispersion shifted fibers (NZDSF) and thulium doped fiber amplifiers (TDFA) in the optical communication system. For the C band we use dispersion shifted fibers (DSF) and erbium doped fiber amplifiers (EDFA). We present eye diagrams and bit error rates for these configurations and we show that soliton transmission in the S band is just as feasible as in the C band, without the use of dispersion management techniques. We also show the effect of two essential elements in the system, the optical bandpass filter and the soliton amplitude modulation.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"6 32","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132880858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"RF-MEMS and its applications to microwave systems, antennas and wireless communications","authors":"C. Christodoulou","doi":"10.1109/IMOC.2003.1244915","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244915","url":null,"abstract":"MEMS-based products combine both mechanical and electronic devices on a monolithic microchip to produce superior performance over solid-state components, especially for wireless applications. RF-MEMS components are mainly used as inductors, tunable capacitors, switches, in VCOs, and resonators. Popular MEMS switches for wireless applications include transmit/receive duplexers, band-mode selection, time delay for phased-array antennas, and reconfigurable antennas. This paper talks about the use of MEMS switches in conjunction of fractal antennas to achieve multi-frequency, reconfigurable antennas that can be used for a variety of communication applications and how micromachining can be used to fabricated new 3-D MEMS antenna structures for very high frequency applications.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127838238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design of integrated inductors through selection from a database created using electromagnetic simulation and neural networks","authors":"R. Kowaltschuk, W. A. Artuzi, O.C. Gouveia Filho","doi":"10.1109/IMOC.2003.1244898","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244898","url":null,"abstract":"The design of integrated inductors on silicon has become an important issue to decrease costs and to speed up the fabrication of telecommunication integrated circuits. Nevertheless, the formulae provided by the existing theory still do not show a good result in inductance prediction, specially if one figures that these inductances must fit the measured ones through a wide band of very high frequency values. Electromagnetic simulation is an alternative to cope with this problem, but if done in a non-ordered fashion, it will demand a lot of computer processing time and will also require a very skilled designer to select the inductors to be tested from a large set of possible devices, due to the large amount of variables involved in the device's specification. The purpose of this work is to propose a methodology to perform electromagnetic simulations in a systematic and automatic way. Once finished these electromagnetic simulations, the resulting electrical parameters are stored in a database that correlates these variables to the geometric specification of the inductors. In order to reduce the computation time demanded by the electromagnetic simulations, the possibility of generating the electrical parameters database using neural networks was also verified.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121175194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Wiederhecker, T. Alegre, A. Rieznik, T.A.R. Branciforte, H. Fragnito
{"title":"Spectral replica holes in the ASE spectra of erbium-doped fibers with different co-doping elements and erbium concentrations","authors":"G. Wiederhecker, T. Alegre, A. Rieznik, T.A.R. Branciforte, H. Fragnito","doi":"10.1109/IMOC.2003.1244841","DOIUrl":"https://doi.org/10.1109/IMOC.2003.1244841","url":null,"abstract":"We report on the observation of spectral replica holes in erbium doped fibers with different co-doping elements. Replica holes in the long wavelength region are enhanced by co-doping with lanthanum. Increasing the erbium concentration tends to wash out replica holes. The width and depth of holes are measured at room (300 K) and low (77 K) temperatures.","PeriodicalId":156662,"journal":{"name":"Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678)","volume":"45 17","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113974095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}