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User Cooperation Diversity -- Part I: System Description

by Andrew Sendonaris, Elza Erkip, Behnaam Aazhang - IEEE TRANS. COMMUN , 1998
"... Mobile users' data rate and quality of service are limited by the fact that, within the duration of any given call, they experience severe variations in signal attenuation, thereby necessitating the use of some type of diversity. In this two-part paper, we propose a new form of spatial diver ..."
Abstract - Cited by 669 (22 self) - Add to MetaCart
diversity, in which diversity gains are achieved via the cooperation of mobile users. Part I describes the user cooperation strategy while Part II focuses on implementation issues and performance analysis. Results show that, even though the inter-user channel is noisy, cooperation leads not only

Tor: The secondgeneration onion router,”

by Roger Dingledine - in 13th USENIX Security Symposium. Usenix, , 2004
"... Abstract We present Tor, a circuit-based low-latency anonymous communication service. This second-generation Onion Routing system addresses limitations in the original design by adding perfect forward secrecy, congestion control, directory servers, integrity checking, configurable exit policies, an ..."
Abstract - Cited by 1229 (33 self) - Add to MetaCart
Abstract We present Tor, a circuit-based low-latency anonymous communication service. This second-generation Onion Routing system addresses limitations in the original design by adding perfect forward secrecy, congestion control, directory servers, integrity checking, configurable exit policies

User cooperation diversitypart I: System description

by Andrew Sendonaris, Elza Erkip, Behnaam Aazhang - IEEE Trans. Commun , 2003
"... Abstract—Mobile users ’ data rate and quality of service are limited by the fact that, within the duration of any given call, they experience severe variations in signal attenuation, thereby necessitating the use of some type of diversity. In this two-part paper, we propose a new form of spatial div ..."
Abstract - Cited by 432 (20 self) - Add to MetaCart
diversity, in which diversity gains are achieved via the cooperation of mobile users. Part I describes the user cooperation strategy, while Part II focuses on implementation issues and performance analysis. Results show that, even though the interuser channel is noisy, cooperation leads not only

A simple cooperative diversity method based on network path selection

by Aggelos Bletsas, Ashish Khisti, David P. Reed, Andrew Lippman - IEEE J. SELECT. AREAS COMMUN , 2006
"... Cooperative diversity has been recently proposed as a way to form virtual antenna arrays that provide dramatic gains in slow fading wireless environments. However, most of the proposed solutions require distributed space–time coding algorithms, the careful design of which is left for future investi ..."
Abstract - Cited by 452 (14 self) - Add to MetaCart
for cooperation between the source and the destination. We develop and analyze a distributed method to select the best relay that requires no topology information and is based on local measurements of the instantaneous channel conditions. This method also requires no explicit communication among the relays

Recognizing action units for facial expression analysis

by Ying-li Tian, Takeo Kanade, Jeffrey F. Cohn - PATTERN ANALYSIS AND MACHINE INTELLIGENCE , 2001
"... Most automatic expression analysis systems attempt to recognize a small set of prototypic expressions, such as happiness, anger, surprise, and fear. Such prototypic expressions, however, occur rather infrequently. Human emotions and intentions are more often communicated by changes in one or a few ..."
Abstract - Cited by 399 (38 self) - Add to MetaCart
Most automatic expression analysis systems attempt to recognize a small set of prototypic expressions, such as happiness, anger, surprise, and fear. Such prototypic expressions, however, occur rather infrequently. Human emotions and intentions are more often communicated by changes in one or a few

Sampling signals with finite rate of innovation

by Martin Vetterli, Pina Marziliano, Thierry Blu - IEEE Transactions on Signal Processing , 2002
"... Abstract—Consider classes of signals that have a finite number of degrees of freedom per unit of time and call this number the rate of innovation. Examples of signals with a finite rate of innovation include streams of Diracs (e.g., the Poisson process), nonuniform splines, and piecewise polynomials ..."
Abstract - Cited by 350 (67 self) - Add to MetaCart
procedures for solving the sampling problem, which we show through experimental results. Applications of these new sampling results can be found in signal processing, communications systems, and biological systems. Index Terms—Analog-to-digital conversion, annihilating filters, generalized sampling

The relay-eavesdropper channel: Cooperation for secrecy

by Lifeng Lai, Hesham El Gamal - IEEE Trans. on Inf. Theory , 2006
"... This paper establishes the utility of user cooperation in facilitating secure wireless communications. In particular, the four-terminal relay-eavesdropper channel is introduced and an outer-bound on the optimal rate-equivocation region is derived. Several cooperation strategies are then devised and ..."
Abstract - Cited by 158 (7 self) - Add to MetaCart
This paper establishes the utility of user cooperation in facilitating secure wireless communications. In particular, the four-terminal relay-eavesdropper channel is introduced and an outer-bound on the optimal rate-equivocation region is derived. Several cooperation strategies are then devised

User Cooperation Diversity - Part II: Implementation Aspects and Performance Analysis

by Andrew Sendonaris, Elza Erkip, Behnaam Aazhang - IEEE Transactions on Communications
"... This is the second in a two-part series of papers on a new form of spatial diver- sity, where diversity gains are achieved through the cooperation of mobile users. Part I described the user cooperation concept and proposed a cooperation strategy for a conventional CDMA system. Part II investigate ..."
Abstract - Cited by 274 (10 self) - Add to MetaCart
investigates the cooperation concept further and considers practical issues related to its implementation. In particular, we investigate the optimal and suboptimal receiver design, and present performance analysis for the conventional CDMA implementation proposed in Part I. We also consider a high rate

Gamal, “On the secrecy capacity of fading channels

by Praveen Kumar Gopala, Lifeng Lai, Hesham El Gamal - in Proc. IEEE Int. Symp. Information Theory (ISIT
"... We consider the secure transmission of information over an ergodic fading channel in the presence of an eavesdropper. Our eavesdropper can be viewed as the wireless counterpart of Wyner’s wiretapper. The secrecy capacity of such a system is characterized under the assumption of asymptotically long c ..."
Abstract - Cited by 203 (9 self) - Add to MetaCart
We consider the secure transmission of information over an ergodic fading channel in the presence of an eavesdropper. Our eavesdropper can be viewed as the wireless counterpart of Wyner’s wiretapper. The secrecy capacity of such a system is characterized under the assumption of asymptotically long

A survey of recent results in networked control systems

by João P. Hespanha, Payam Naghshtabrizi, Yonggang Xu - PROCEEDINGS OF THE IEEE , 2007
"... Networked Control Systems (NCSs) are spatially distributed systems for which the communication between sensors, actuators, and controllers is supported by a shared communication network. In this paper we review several recent results on estimation, analysis, and controller synthesis for NCSs. The re ..."
Abstract - Cited by 300 (11 self) - Add to MetaCart
Networked Control Systems (NCSs) are spatially distributed systems for which the communication between sensors, actuators, and controllers is supported by a shared communication network. In this paper we review several recent results on estimation, analysis, and controller synthesis for NCSs
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