Institution
Alcatel-Lucent
Stuttgart, Germany•
About: Alcatel-Lucent is a based out in Stuttgart, Germany. It is known for research contribution in the topics: Signal & Network packet. The organization has 37003 authors who have published 53332 publications receiving 1430547 citations. The organization is also known as: Alcatel-Lucent S.A. & Alcatel.
Papers published on a yearly basis
Papers
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TL;DR: A parallel-pipelined A/D converter with an area and power efficient architecture is described and an 8-b pipeline is realized using just three amplifiers (instead of seven amplifiers with a conventional pipeline architecture).
Abstract: A parallel-pipelined A/D converter with an area and power efficient architecture is described. By sharing amplifiers along the pipeline and also completely eliminating the amplifier from the last stage, an 8-b pipeline is realized using just three amplifiers (instead of seven amplifiers with a conventional pipeline architecture). By using two such pipelines in parallel, a 52 Msamples/s prototype A/D converter that is Intended for a switched digital video application has been implemented in a 0.9-/spl mu/m CMOS technology. The device occupies 15 mm/sup 2/ and dissipates 250 mW from a 5 V supply.
225 citations
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21 Mar 1999TL;DR: This paper presents a new approach to overcome the problem of feedback collision in single channel multi-access wireless LANs, both for the purpose of acquiring the channel and for reliability, and presents a simple scheme for leader election.
Abstract: Multicast is an efficient paradigm for transmitting data from a sender to a group of receivers. In this paper, we focus on multicast in single channel multi-access wireless local area networks (LANs) comprising several small cells. In such a system, a receiver cannot correctly receive a packet if two or more packets are sent to it at the same time, because the packets "collide". Therefore, one has to ensure that only one node sends at a time. We look at two important issues. First, we consider the problem of the sender acquiring the multi-access channel for multicast transmission. Second, for reliable multicast in each cell of the wireless LAN, we examine ARQ-based approaches. The second issue is important because the wireless link error rates can be very high. We present a new approach to overcome the problem of feedback collision in single channel multi-access wireless LANs, both for the purpose of acquiring the channel and for reliability. Our approach involves the election of one of the multicast group members (receivers) as a "leader" or representative for the purpose of sending feedback to the sender. For reliable multicast, on erroneous reception of a packet, the leader does not send an acknowledgement, prompting a retransmission. On erroneous reception of the packet at receivers other than the leader, our protocol allows negative acknowledgements from these receivers to collide with the acknowledgement from the leader thus destroying the acknowledgement and prompting the sender to retransmit the packet. Using analytical models, we demonstrate that the leader-based protocol exhibits higher throughput in comparison to two other protocols which use traditional delayed feedback-based probabilistic methods. Last, we present a simple scheme for leader election.
225 citations
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TL;DR: In this article, the microseparation of hydrophobic components from hydrophilic ones (water and surfactant heads) was simulated by a Monte Carlo technique in a lattice model of mixtures of idealized surfactants, oil, and water molecules.
Abstract: In a lattice model of mixtures of idealized surfactant, oil, and water molecules, the microseparation of hydrophobic components (oil and surfactant tails) from hydrophilic ones (water and surfactant heads) is simulated by a Monte Carlo technique In water, symmetric surfactants, ie, with heads as long as the tails, achieve lamellar or hexagonal‐cylindrical order as the temperature is reduced; the lamellae and cylinders form at surfactant concentrations that are similar to the concentrations at which symmetric block copolymers mixed with homopolymers have been found to form these structures The lamellae containing tails can have many holes; as the temperature is reduced the holes attain hexagonal order within each layer At low concentrations in water, symmetric surfactants form spherical micelles; the size distribution of these is computed, as well as the critical micelle concentration When the surfactant tail is larger than the head, the micelles are cigar shaped or cylindrical Cylindrical micelles can intersect each other to form a bicontinuous phase Other disordered bicontinuous phases, including a symmetric spongelike phase, are observed, and the validity of film theories for these phases is examined
225 citations
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TL;DR: Pulses of 90-fsec duration from a cavity-dumped colliding-pulse mode-locked laser have been amplified to microjoule energies at 5-kHz repetition rate using a copper-vapor-laser pump source.
Abstract: Pulses of 90-fsec duration from a cavity-dumped colliding-pulse mode-locked laser have been amplified to microjoule energies at 5-kHz repetition rate using a copper-vapor-laser pump source. Near-diffraction-limited focusing and efficient femtosecond continuum generation are demonstrated.
225 citations
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TL;DR: A new and simple analytical framework is presented to model dual-polarized Rayleigh and Ricean fading channels for arbitrary array sizes and investigates the multiplexing advantage of dual- polarized transmissions through the evaluation of the ergodic mutual information.
Abstract: In this paper, we address the potential benefits of dual-polarized arrays in multi-antenna wireless systems. After an extensive literature overview of experimental data, we present a new and simple analytical framework to model dual-polarized Rayleigh and Ricean fading channels for arbitrary array sizes. The model relies on a limited number of physical parameters, such as the channel spatial correlations, the channel co-polar and the cross-polar ratios and the antenna cross-polar discrimination. Then, we investigate the multiplexing advantage of dual-polarized transmissions through the evaluation of the ergodic mutual information, for both TITO and MIMO systems. Finally, the performance of two space-time coding schemes (Alamouti OSTBC and uncoded spatial multiplexing) is evaluated via a detailed analysis of the pairwise error probability.
224 citations
Authors
Showing all 37011 results
Name | H-index | Papers | Citations |
---|---|---|---|
George M. Whitesides | 240 | 1739 | 269833 |
Yoshua Bengio | 202 | 1033 | 420313 |
John A. Rogers | 177 | 1341 | 127390 |
Zhenan Bao | 169 | 865 | 106571 |
Thomas S. Huang | 146 | 1299 | 101564 |
Federico Capasso | 134 | 1189 | 76957 |
Robert S. Brown | 130 | 1243 | 65822 |
Christos Faloutsos | 127 | 789 | 77746 |
Robert J. Cava | 125 | 1042 | 71819 |
Ramamoorthy Ramesh | 122 | 649 | 67418 |
Yann LeCun | 121 | 369 | 171211 |
Kamil Ugurbil | 120 | 536 | 59053 |
Don Towsley | 119 | 883 | 56671 |
Steven P. DenBaars | 118 | 1366 | 60343 |
Robert E. Tarjan | 114 | 400 | 67305 |