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11.
Ricardo A. Aroca C. Andre T. Salama 《Analog Integrated Circuits and Signal Processing》2006,48(3):167-174
This paper presents the design and implementation of a new wide dynamic range parallel feedback (PF) transimpedance amplifier
(TIA) for 10 Gb/s optical links. The wide dynamic range is attributed to the novel TIA architecture employing both shunt-shunt
and shunt-series feedback networks. The outstanding features of the TIA are wide dynamic range, high gain, low power consumption
and design simplicity. A prototype implemented in a 0.5 μm SiGe BiCMOS technology and operating at −3.3 V power supply features
an 18.4 dBm dynamic range with a BER less than 10−12, an optical sensitivity of −16 dBm, optical overload of +2.4 dBm, a bandwidth of 8.27 GHz, a gain of 950 Ω and a power consumption
of 189 mW. The new parallel feedback architecture offers improved overload and noise performance when compared to previously
reported, state of the art, single feedback TIA designs and meets all the 10 Gigabit Ethernet and short-reach OC-192 SONET
specifications.
Ricardo Andres Aroca received the B.S. (Hons) degree in electrical engineering from the University of Windsor, Canada, and the M.S. degree from
the University of Toronto, Canada, in 2001 and 2004, respectively. In 2000 he spent two 4 month internships with Nortel Networks
in the Microelectronics Department. Mr. Aroca received the Natural Sciences and Engineering Research Counsel of Canada (NSERC)
Postgraduate Scholarship award in 2002. He is currently working toward the Ph.D. degree at the University of Toronto where
his research interests lie in the area of high-frequency integrated circuits for wireless and wireline communication systems.
C. Andre T. Salama received the B.A.Sc. (Hons.) M.A.Sc. and Ph. D. degrees, all in Electrical Engineering, from the University of British Columbia
in 1961, 1962 and 1966 respectively. From 1962 to 1963 he served as a Research Assistant at the University of California,
Berkeley. From 1966 to 1967 he was employed at Bell Northern Research, Ottawa, as a Member of Scientific Staff working in
the area of integrated circuit design. Since 1967 he has been on the staff of the Department of Electrical and Computer Engineering,
University of Toronto where he held the J.M. Ham Chair in Microelectronics from 1987 to 1997. In 1992, he was appointed to
his present position of University Professor for scholarly achievements and preeminence in the field of microelectronics.
In 1989-90, he was awarded the ITAC/NSERC Research Fellowship in information technology. In 1994, he was awarded the Canada
Council I.W. Killam Memorial Prize in Engineering for outstanding career contributions to the field of microelectronics. In
2000, he received the IEEE Millenium Medal. In 2003, he received the Outstanding Lifetime Achievement Award from the Canadian
Semiconductor Technology Conference for seminal and outstanding contributions to semiconductor device research and promotion
of Canadian University research in microelectronics. In 2004, he received the NSERC Lifetime Achievement Award of Research
Excellence for outstanding and sustained contributions to the field of microelectronics and the Networks of Centres of Excellence
(NCE) Recognition Award for research excellence and outstanding leadership.He was associate editor of the IEEE Transactions
on Circuits and Systems in 1986–88 and a member of the International Electron Devices Meeting (IEDM) Technical Program Committeein
1980–82, 1987–89 and 1996–98. He was the chair of the Solid State Devices Subcommittee for IEDM in 1998 and was a member of
the editorial board of Solid State Electronics from 1984 to 2002. He is presently a member of the editorial board of the Analog
IC and Signal Processing Journal and the Technical Program Committee of the International Symposium on Power Semiconductor
Devices and ICs (ISPSD) and the Technical ProgramCommittee of the International Symposium on Low Power Electronics and Design
(ISLPED). He chaired the technical program committee of ISPSD in 1996 and was the general chair for the conference in 1999.Dr.
Salama is the Scientific Director of Micronet, a network of centres of excellence focussing on microelectronics research and
funded by the Canadian Government and Industry. He has published extensively in technical journals, is the holder of eleven
patents and has served as a consultant to the semiconductor industry in Canada and the U.S. His research interests include
the design and fabrication of semiconductor devices and integrated circuits with emphasis on deep submicron devices as well
as circuits and systems for high speed, low power signal processing applications. Dr. Salama is a Fellow of the Institute
of Electrical and Electronics Engineers, a Fellow of the Royal Society of Canada, a Fellow of the Canadian Academy of Engineering,
a member of the Association of Professional Engineers of Ontario, the Electrochemical Society and the Innovation Management
Association of Canada. 相似文献
12.
Energy management system (EMS) computer architectures have changed significantly over the recent past increasing the difficulty and the need for a priori assessment of system performance and dependability. The old practice based on measurements is no longer acceptable because of the flexibility accrued with the deployment of the new distributed computer-based systems. The number of “what if” questions increased since EMS systems are now implemented using multiple workstations that can be interconnected in various different ways.In this paper we show how alternative configurations can be modeled and analyzed, before proposing and purchasing any equipment, with the assistance of Markov reward models. We review the concept of Markov reward models and show how they can be applied in the availability analysis of SCADA/EMS computer systems. The paper also presents a software tool that facilitates automatic generation and solution of large Markov reward models. The input language of this modeling tool uses a variation of stochastic Petri nets called stochastic reward nets, which are also reviewed. We believe this is the first time a detailed quantitative model of a SCADA/EMS computer system is proposed and solved in the general literature. 相似文献
13.
14.
SPETA: Social pervasive e-Tourism advisor 总被引:1,自引:0,他引:1
Angel García-Crespo Javier Chamizo Ismael Rivera Myriam Mencke Ricardo Colomo-Palacios Juan Miguel Gómez-Berbís 《Telematics and Informatics》2009
Tourism is one of the major sources of income for many countries. Therefore, providing efficient, real-time service for tourists is a crucial competitive asset which needs to be enhanced using major technological advances. The current research has the objective of integrating technological innovation into an information system, in order to build a better user experience for the tourist. The principal strength of the approach is the fusion of context-aware pervasive systems, GIS systems, social networks and semantics. This paper presents the SPETA system, which uses knowledge of the user’s current location, preferences, as well as a history of past locations, in order to provide the type of recommender services that tourists expect from a real tour guide. 相似文献
15.
16.
17.
Intrinsic selectivities and yields in the catalytic hydrogenation of polyenoic fatty acid methyl esters 总被引:1,自引:0,他引:1
Ricardo J. Grau Alberto E. Cassano Miguel A. Balfanás 《Journal of the American Oil Chemists' Society》1990,67(4):226-232
Precise values of the intrinsic selectivities and yields for the hydrogenation products of methyl linolenate (Ln) and methyl
linoleate (L) obtained under carefully controlled conditions using a commercial Ni catalyst are presented and analyzed in
detail. The existence of a preferential adsorption of Ln and a significant co-hydrogenation of its double bonds are confirmed
as being the dominant features under typical vegetable oil processing conditions.
It is shown that the values of the selectivities that are obtained from the classical consecutive reactions network account
for the intrinsic selectivity of the catalyst only while hydrogenating feedstocks with moderate to low (<10%) contents of
Ln.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional del Lltoral (U.N.L.) 相似文献
18.
Garrocho Charles T. B. da Silva Maurício J. Oliveira Ricardo A. R. 《Wireless Networks》2020,26(1):373-386
Wireless Networks - D2D (device-to-device) communication is one of the developments of 5G networks (5th generation mobile networks) that reduce mobile traffic load, reduce energy consumption and... 相似文献
19.
Technological evolution is leading telecommunications toward all-IP scenarios, where multiple services are transported as
IP packets. Among these services is the broadcast of video. A possible mechanism for broadcasting multiple video channels
over IP is to use IP multicast, and let each client decide about the reception of a channel. The secure IP multicast specified
by the IETF MSEC working group is a candidate solution for securing these broadcast services. In this paper we propose a new
solution for supporting the broadcast of multiple video channels which can be accessed only by authorized users; besides,
when a video channel is not visualized in the last mile its transmission is temporarily suspended, so that the cable can be
used for other services such as standard Internet access. 相似文献
20.
Yanqing Deng Roland Kersting Victor Roytburd Jingzhou Xu Ricardo Ascazubi Kai Liu Xi-Cheng Zhang Michael S. Shur 《Journal of Infrared, Millimeter and Terahertz Waves》2004,25(2):215-228
We describe a method to determine the radiation spectrum of terahertz sources using a transmitted Fabry-Perot interferometer and a bolometer detector. Our novel Fabry-Perot spectrometer can measure the spectrum of an unknown broadband sub-terahertz and terahertz source. The spectrometer does not need to be pre-tuned. We develop a new algorithm to support the measurements using this spectrometer. Our technique allows us to measure the spectrum over more than an octave, and our numerical algorithm is very stable and robust, providing for an accurate spectrum determination. Two Gunn oscillation sources with the main frequencies at 200 GHz and 600 GHz are used to test the proposed method. The spectrum extracted from the measured data shows that this method is accurate and reliable. 相似文献