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Performance Analysis of the IEEE 802.11 Distributed Coordination Function

by Giuseppe Bianchi , 2000
"... Recently, the IEEE has standardized the 802.11 protocol for Wireless Local Area Networks. The primary medium access control (MAC) technique of 802.11 is called distributed coordination function (DCF). DCF is a carrier sense multiple access with collision avoidance (CSMA/CA) scheme with binary slott ..."
Abstract - Cited by 1869 (1 self) - Add to MetaCart
slotted exponential backoff. This paper provides a simple, but nevertheless extremely accurate, analytical model to compute the 802.11 DCF throughput, in the assumption of finite number of terminals and ideal channel conditions. The proposed analysis applies to both the packet transmission schemes

The struggle to govern the commons

by Thomas Dietz, Elinor Ostrom, Paul C. Stern - Science , 2003
"... Human institutions—ways of organizing activities—affect the resilience of the environ-ment. Locally evolved institutional arrangements governed by stable communities and buffered from outside forces have sustained resources successfully for centuries, al-though they often fail when rapid change occu ..."
Abstract - Cited by 661 (17 self) - Add to MetaCart
occurs. Ideal conditions for governance are increasingly rare. Critical problems, such as transboundary pollution, tropical deforesta-tion, and climate change, are at larger scales and involve nonlocal influences. Promising strategies for addressing these problems include dialogue among interested

Design of capacity-approaching irregular low-density parity-check codes

by Thomas J. Richardson, M. Amin Shokrollahi, Rüdiger L. Urbanke - IEEE TRANS. INFORM. THEORY , 2001
"... We design low-density parity-check (LDPC) codes that perform at rates extremely close to the Shannon capacity. The codes are built from highly irregular bipartite graphs with carefully chosen degree patterns on both sides. Our theoretical analysis of the codes is based on [1]. Assuming that the unde ..."
Abstract - Cited by 588 (6 self) - Add to MetaCart
that the underlying communication channel is symmetric, we prove that the probability densities at the message nodes of the graph possess a certain symmetry. Using this symmetry property we then show that, under the assumption of no cycles, the message densities always converge as the number of iterations tends

Versatile Low Power Media Access for Wireless Sensor Networks

by Joseph Polastre, Jason Hill, David Culler , 2004
"... We propose B-MAC, a carrier sense media access protocol for wireless sensor networks that provides a flexible interface to obtain ultra low power operation, effective collision avoidance, and high channel utilization. To achieve low power operation, B-MAC employs an adaptive preamble sampling scheme ..."
Abstract - Cited by 1099 (19 self) - Add to MetaCart
We propose B-MAC, a carrier sense media access protocol for wireless sensor networks that provides a flexible interface to obtain ultra low power operation, effective collision avoidance, and high channel utilization. To achieve low power operation, B-MAC employs an adaptive preamble sampling

Segmentation of brain MR images through a hidden Markov random field model and the expectation-maximization algorithm

by Yongyue Zhang, Michael Brady, Stephen Smith - IEEE TRANSACTIONS ON MEDICAL. IMAGING , 2001
"... The finite mixture (FM) model is the most commonly used model for statistical segmentation of brain magnetic resonance (MR) images because of its simple mathematical form and the piecewise constant nature of ideal brain MR images. However, being a histogram-based model, the FM has an intrinsic limi ..."
Abstract - Cited by 639 (15 self) - Add to MetaCart
The finite mixture (FM) model is the most commonly used model for statistical segmentation of brain magnetic resonance (MR) images because of its simple mathematical form and the piecewise constant nature of ideal brain MR images. However, being a histogram-based model, the FM has an intrinsic

Tabu Search -- Part I

by Fred Glover , 1989
"... This paper presents the fundamental principles underlying tabu search as a strategy for combinatorial optimization problems. Tabu search has achieved impressive practical successes in applications ranging from scheduling and computer channel balancing to cluster analysis and space planning, and more ..."
Abstract - Cited by 680 (11 self) - Add to MetaCart
This paper presents the fundamental principles underlying tabu search as a strategy for combinatorial optimization problems. Tabu search has achieved impressive practical successes in applications ranging from scheduling and computer channel balancing to cluster analysis and space planning

Just Relax: Convex Programming Methods for Identifying Sparse Signals in Noise

by Joel A. Tropp , 2006
"... This paper studies a difficult and fundamental problem that arises throughout electrical engineering, applied mathematics, and statistics. Suppose that one forms a short linear combination of elementary signals drawn from a large, fixed collection. Given an observation of the linear combination that ..."
Abstract - Cited by 483 (2 self) - Add to MetaCart
. This paper studies a method called convex relaxation, which attempts to recover the ideal sparse signal by solving a convex program. This approach is powerful because the optimization can be completed in polynomial time with standard scientific software. The paper provides general conditions which ensure

A Digital Fountain Approach to Reliable Distribution of Bulk Data

by Michael Luby, et al. , 1998
"... The proliferation of applications that must reliably distribute bulk data to a large number of autonomous clients motivates the design of new multicast and broadcast protocols. We describe an ideal, fully scalable protocol for these applications that we call a digital fountain. A digital fountain a ..."
Abstract - Cited by 492 (19 self) - Add to MetaCart
The proliferation of applications that must reliably distribute bulk data to a large number of autonomous clients motivates the design of new multicast and broadcast protocols. We describe an ideal, fully scalable protocol for these applications that we call a digital fountain. A digital fountain

A Rate-Adaptive MAC Protocol for Multi-Hop Wireless Networks

by Gavin Holland, Nitin H. Vaidya, Paramvir Bahl , 2001
"... Wireless local area networks (W-LANs) have become increasingly popular due to the recent availability of affordable devices that are capable of communicating at high data rates. These high rates are possible, in part, through new modulation schemes that are optimized for the channel conditions bring ..."
Abstract - Cited by 484 (5 self) - Add to MetaCart
Wireless local area networks (W-LANs) have become increasingly popular due to the recent availability of affordable devices that are capable of communicating at high data rates. These high rates are possible, in part, through new modulation schemes that are optimized for the channel conditions

Ultra-wide bandwidth time-hopping spread spectrum impulse radio for wireless access communications

by Moe Z. Win, Robert A. Scholtz - IEEE TRANS. COMMUN , 2000
"... Attractive features of time-hopping spread-spectrum multiple-access systems employing impulse signal technology are outlined, and emerging design issues are described. Performance of such communications systems in terms of achievable transmission rate and multiple-access capability are estimated fo ..."
Abstract - Cited by 456 (16 self) - Add to MetaCart
for both analog and digital data modulation formats under ideal multiple-access channel conditions.
Results 1 - 10 of 23,835