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Blaise Ravelo

Bio: Blaise Ravelo is an academic researcher from Nanjing University of Information Science and Technology. The author has contributed to research in topics: Group delay and phase delay & Microstrip. The author has an hindex of 21, co-authored 196 publications receiving 1727 citations. Previous affiliations of Blaise Ravelo include École Supérieure d'Ingénieurs en Génie Électrique & Nanjing University.


Papers
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Proceedings ArticleDOI
13 May 2007
TL;DR: A technique to compensate the propagation delay and losses in VLSI interconnects by using negative group delay (NGD) active circuits based on a cell consisting of a Field Effect Transistor in parallel with a series RL passive network is proposed.
Abstract: In this paper, we propose a technique to compensate the propagation delay and losses in VLSI interconnects by using negative group delay (NGD) active circuits This study uses the RLC models of interconnect lines currently considered in VLSI circuits The circuit proposed here is based on a cell consisting of a Field Effect Transistor (FET) in parallel with a series RL passive network We also describe the synthesis method to achieve simultaneousely a significant negative group delay and gain Simulations allow us to first verify the performance of the NGD circuit and also show a restoration of the distorted signal shape as well as a reduction of propagation delay

17 citations

Journal ArticleDOI
TL;DR: In this paper, an original equalization method of 3-D electromagnetic (EM) cavity resonance by using bandpass negative group delay (NGD) function based on the equivalent circuit, the S -matrix model of the equalized EM cavity is introduced.
Abstract: This article deals with an original equalization method of 3-D electromagnetic (EM) cavity resonance by using bandpass negative group delay (NGD) function Based on the equivalent circuit, the S -matrix model of the equalized EM cavity is introduced The design equations of the NGD function are established in function of the cavity physical parameters The feasibility of the equalization method is validated with a 42×28×38 cm rectangular cavity containing two communicating monopole antennas By considering the TE110-mode, a significant equalization is realized with improvement of transmission coefficient flatness from 4 dB to less than 03 dB In addition to the magnitude, the NGD equalization method enables to outstandingly reduce spikes of 3-D EM cavity group delay With the proof of concept, the GD is reduced from more than 4 to 1 ns

16 citations

Journal ArticleDOI
Abstract: This paper deals with planar scanning technique of electromagnetic (EM) near-fleld (NF) emitted by electronic printed circuit boards (PCBs) fully in the time-domain (TD). The proposed EM scanning metrology is essentially based on the NF test bench available at the IRSEEM laboratory. It comprises motorized mechanical structures for moving the probe interconnected to electronic measurement instruments and controlled by a driver PC. The synoptic of the test bench is presented and technically examined. The characteristics of difierent elements constituting the measurement chain of the TD test bench understudy are described. The NF metrology developed is originally focused on the measurement of time-dependent magnetic fleld H(t) dedicated to the radiated emission electromagnetic compatibility (EMC) applications. An innovative calibration technique of the loop probe for detecting H(t) is established in order to ensure the post processing and extraction of the measured NF data. Then, validations were carried out via comparison with difierent simulations run with standard commercial tools. Mathematical analyses were also conducted for the improvement of the measurement post processing. To realize the mapping of time-dependent EM fleld components, a software interface edited with the graphical language LabVIEW was emulated to synchronize the probe displacement and the data acquisition. An UWB amplifler with average gain about 30dB from DC to 300MHz was designed and fabricated in order to decrease the measurement noise and to improve the quality of measured signals. As results of the study, TD NF mapping is demonstrated successfully by measuring the EM radiation emitted by electronic planar circuits. The technique developed is extremely useful in the fleld of EMC engineering for predicting the transient perturbations susceptible to degrade electronic functions in complex systems encountered usually for the automotive and aeronautic applications.

16 citations

Journal ArticleDOI
TL;DR: This brief describes a synthesis of high-pass negative group delay (NGD) network impedance based on the circuit impedance equivalent principle, and a good agreement between the theoretical prediction and experimental results shows high- pass NGD response from 1 MHz with minimal level of about −10 ns.
Abstract: This brief describes a synthesis of high-pass negative group delay (NGD) network impedance. The fundamental expression of the high-pass NGD canonical transfer function is established. Based on the circuit impedance equivalent principle, the high-pass NGD first-order network that is constituted by RC lumped elements is identified. The identified topology basic NGD characteristics are formulated and analyzed. Then, the associated synthesis method in function of the desired NGD optimal level and cutoff frequency is established. The theory is validated by design, simulations, and measurements of proof-of-concept prototypes. A good agreement between the theoretical prediction and experimental results showing high-pass NGD response from 1 MHz with minimal level of about −10 ns is observed. The high-pass NGD function operates at high frequencies with first-order circuit.

16 citations

Proceedings ArticleDOI
12 May 2008
TL;DR: A new method developed to reduce the propagation delay by using a negative group delay (NGD) active circuit using a high-frequency circuit simulator showed that the 50% propagation delay was reduced by 94%.
Abstract: This paper presents a new method developed to reduce the propagation delay by using a negative group delay (NGD) active circuit. Analytical expressions are proposed to demonstrate the validity of our approach in the case of an RC-transmission line model. The synthesis method of NGD circuits versus the line length is detailed. For a 0.5 Gbit/s digital signal and a 2-cm-long RC-line model, time-domain simulations carried out with a high-frequency circuit simulator showed that the 50% propagation delay was reduced by 94%. Finally, potential applications of this method to compensate for time delays in different interconnect configurations (VLSI, package, on-chip, long-line, ...) are discussed.

15 citations


Cited by
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Book
01 Jan 1960

1,106 citations

Journal ArticleDOI
TL;DR: This is really two separate books within the same pair of covers, which are devoted to the discussion of similarity and dimensional, methods and their application to a variety of problems in mechanics and fluid mechanics.
Abstract: By L I Sedov London: Cleaver-Hume Press Ltd Pp xvi + 363 Price 105s This is really two separate books within the same pair of covers First of all Chapters 1-3, some 145 pages, are devoted to the discussion of similarity and dimensional, methods and their application to a variety of problems in mechanics and fluid mechanics

697 citations

Journal ArticleDOI
01 Nov 1951-Nature
TL;DR: In this article, Sommerfeld presents a review of the theoretic aspects of Physik, including Mechanik, Elektrodynamik and Partielle Differentialgleichungen der Physik.
Abstract: Vorlesungen uber theoretische Physik Von Prof. Arnold Sommerfeld. Band 1: Mechanik. Vierte, neubearbeitete Auflage. Pp. xii + 276. 18 D. marks. Band 2: Mechanik der deformierbaren Medien. Pp. xv + 376 + 4 plates. 18 D. marks. Band 3: Elektrodynamik. Pp. xvi + 368. 18 D. marks. Band 6: Partielle Differentialgleichungen der Physik. Pp. xiii + 332. 18 D. marks. (Wiesbaden: Dieterich'sche Verlagsbuchhandlung, 1947–1949.)

669 citations

Journal ArticleDOI
TL;DR: A new prototype triboelectric nanogenerator with superhydrophobic and self-cleaning features is invented to harvest water drop energy based on a sequential contact electrification and electrostatic induction process.
Abstract: A new prototype triboelectric nanogenerator with superhydrophobic and self-cleaning features is invented to harvest water drop energy based on a sequential contact electrification and electrostatic induction process. Because of the easy-fabrication, cost-effectiveness, and robust properties, the developed triboelectric nanogenerator expands the potential applications to harvesting energy from household wastewater and raindrops.

544 citations