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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
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Journal ArticleDOI
TL;DR: An overview of important topics and applications in the context of relaying covers different approaches to exploiting the benefits of multihop communications via relays, such as solutions for radio range extension in mobile and wireless broadband cellular networks and solutions to combat shadowing at high radio frequencies.
Abstract: In recent years, there has been an upsurge of interest in multihop-augmented infrastructure-based networks in both the industry and academia, such as the seed concept in 3GPP, mesh networks in IEEE 802.16, and converge extension of HiperLAN/2 through relays or user-cooperative diversity mesh networks. This article, a synopsis of numerous contributions to the working group 4 of the wireless world research forum and other research work, presents an overview of important topics and applications in the context of relaying. It covers different approaches to exploiting the benefits of multihop communications via relays, such as solutions for radio range extension in mobile and wireless broadband cellular networks (trading range for capacity), and solutions to combat shadowing at high radio frequencies. Furthermore, relaying is presented as a means to reduce infrastructure deployment costs. It is also shown that through the exploitation of spatial diversity, multihop relaying can enhance capacity in cellular networks. We wish to emphasize that while this article focuses on fixed relays, many of the concepts presented can also be applied to systems with moving relays.

1,907 citations

Journal ArticleDOI
TL;DR: Using this joint space-time approach, spectral efficiencies ranging from 20-40 bit/s/Hz have been demonstrated in the laboratory under flat fading conditions at indoor fading rates.
Abstract: The signal detection algorithm of the vertical BLAST (Bell Laboratories Layered Space-Time) wireless communications architecture is briefly described. Using this joint space-time approach, spectral efficiencies ranging from 20-40 bit/s/Hz have been demonstrated in the laboratory under flat fading conditions at indoor fading rates. Early results are presented.

1,791 citations

Journal ArticleDOI
31 Oct 1996-Nature
TL;DR: In this article, it was shown that light emission from single fluorescing nanocrystals of cadmium selenide under continuous excitation turns on and off intermittently with a characteristic timescale of about 0.5 seconds.
Abstract: SEMICONDUCTOR nanocrystals offer the opportunity to study the evolution of bulk materials properties as the size of a system increases from the molecular scale1,2. In addition, their strongly size-dependent optical properties render them attractive candidates as tunable light absorbers and emitters in optoelectronic devices such as light-emitting diodes3,4 and quantum-dot lasers5,6, and as optical probes of biological systems7. Here we show that light emission from single fluorescing nanocrystals of cadmium selenide under continuous excitation turns on and off intermittently with a characteristic timescale of about 0.5 seconds. This intermittency is not apparent from ensemble measurements on many nanocrystals. The dependence on excitation intensity and the change in on/off times when a passivating, high-bandgap shell of zinc sulphide encapsulates the nanocrystal8,9 suggests that the abrupt turning off of luminescence is caused by photo-ionization of the nanocrystal. Thus spectroscopic measurements on single nanocrystals can reveal hitherto unknown aspects of their photophysics.

1,757 citations

Journal ArticleDOI
TL;DR: A general overview of areas in which this has been persuasively demonstrated and, in so doing, suggest the intellectual issues that drive current research in this field can be found in this paper.
Abstract: Interest in the properties of thin-film organic materials, especially regard­ ing organized monoand multilayer assemblies, has grown enormously in recent years. The impetus for this renaissance-the relevance of such structures and materials to biological interfaces and membranes, corrosion protection, electrochemistry, wetting, adhesion, and microelectronic cir­ cuit fabrication, for example-has been discussed extensively (1,2). Such materials are clearly contributing significantly to our more general under­ standing of the physics and chemistry of complex surfaces and interfaces. In this article, we provide a general overview of areas in which this has been persuasively demonstrated and, in so doing, suggest the intellectual issues that drive current research in this field. Until recently, there were no generally applicable methods to construct well-ordered, organic surface phases by using any rational synthetic scheme. Metal, semiconductor, and oxide surfaces can be easily prepared by orienting, cutting (or cleaving), and polishing single-crystal substrates followed by cleaning in ultrahigh vacuum (URV) (i.e. by ion bom-

1,729 citations

Proceedings ArticleDOI
30 Oct 2006
TL;DR: In this paper, the authors proposed a searchable symmetric encryption (SSE) scheme for the multi-user setting, where queries to the server can be chosen adaptively during the execution of the search.
Abstract: Searchable symmetric encryption (SSE) allows a party to outsource the storage of its data to another party (a server) in a private manner, while maintaining the ability to selectively search over it. This problem has been the focus of active research in recent years. In this paper we show two solutions to SSE that simultaneously enjoy the following properties: Both solutions are more efficient than all previous constant-round schemes. In particular, the work performed by the server per returned document is constant as opposed to linear in the size of the data. Both solutions enjoy stronger security guarantees than previous constant-round schemes. In fact, we point out subtle but serious problems with previous notions of security for SSE, and show how to design constructions which avoid these pitfalls. Further, our second solution also achieves what we call adaptive SSE security, where queries to the server can be chosen adaptively (by the adversary) during the execution of the search; this notion is both important in practice and has not been previously considered.Surprisingly, despite being more secure and more efficient, our SSE schemes are remarkably simple. We consider the simplicity of both solutions as an important step towards the deployment of SSE technologies.As an additional contribution, we also consider multi-user SSE. All prior work on SSE studied the setting where only the owner of the data is capable of submitting search queries. We consider the natural extension where an arbitrary group of parties other than the owner can submit search queries. We formally define SSE in the multi-user setting, and present an efficient construction that achieves better performance than simply using access control mechanisms.

1,673 citations


Authors

Showing all 37011 results

NameH-indexPapersCitations
George M. Whitesides2401739269833
Yoshua Bengio2021033420313
John A. Rogers1771341127390
Zhenan Bao169865106571
Thomas S. Huang1461299101564
Federico Capasso134118976957
Robert S. Brown130124365822
Christos Faloutsos12778977746
Robert J. Cava125104271819
Ramamoorthy Ramesh12264967418
Yann LeCun121369171211
Kamil Ugurbil12053659053
Don Towsley11988356671
Steven P. DenBaars118136660343
Robert E. Tarjan11440067305
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
20231
202212
202130
202050
201983
2018215