Concept

Carrier Sense Multiple Access with Collision Avoidance

Publications associées (30)

Neighbor discovery with reception status feedback to transmitters

Neighbor discovery is essential for the process of self-organization of a wireless network, where almost all routing and medium access protocols need knowledge of one-hop neighbors. In this paper we study the problem of neighbor discovery in a static and s ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2010

Self-Organization Properties of CSMA/CA Systems and Their Consequences on Fairness

Patrick Thiran, Olivier Dousse, Mathilde Durvy

Decentralized medium access control schemes for wireless networks based on CSMA/CA, such as the IEEE 802.11 protocol, are known to be unfair. In multihop networks, they can even favor some links to such an extent that the others suffer from virtually compl ...

Institute of Electrical and Electronics Engineers2009

Cooperative coding on orthogonal information networks

Dinkar Vasudevan

The focus of this thesis is on communication over cooperative information networks. In the first half of the thesis, we consider lossy source coding problems where a relay assists in the communication of a source stream between two terminals. The following ...

EPFL2009

On the Fairness of Large CSMA Networks

Patrick Thiran, Olivier Dousse, Mathilde Durvy

We characterize the fairness of decentralized medium access control protocols based on CSMA/CA, such as IEEE 802.11, in large multi-hop wireless networks. In particular, we show that the widely observed unfairness of the protocol in small network topologie ...

Institute of Electrical and Electronics Engineers2009

Elucidating the Instability of Random Access Wireless Mesh Networks

Patrick Thiran, Adel Aziz, David Starobinski

We investigate both theoretically and experimentally the stability of CSMA-based wireless mesh networks, where a network is said to be stable if and only if the queue of each relay node remains (almost surely) finite. We identify two key factors that impac ...

2009

A Fast On-Board Relative Positioning Module for Multi-Robot Systems

Alcherio Martinoli, James Pugh, Xavier Raemy, Riccardo Falconi, Cédric Favre

We present an on-board robotic module which can determine relative positions among miniature robots. The module uses high-frequency modulated infrared emissions to enable nearby robots to determine the range, bearing, and message of the sender with a rapid ...

2009

Neighbor Discovery in Wireless Networks and the Coupon Collector's Problem

Ramin Khalili

Neighbor discovery is one of the first steps in the initialization of a wireless ad hoc network. In this paper, we design and analyze practical algorithms for neighbor discovery in wireless networks. We first consider an ALOHA-like neighbor discovery algor ...

2009

Effect of 802.11 Adaptive Exponential Backoffs on the Fluidity of Downlink Flows in Mesh Networks

Patrick Thiran, Adel Aziz

Efficient multihop traffic management is a need for successful Wireless Mesh Networks (WMNs) deployment. Using an analogy with fluid mechanism, we classify a flow as laminar if the packets flow smoothly from the Wired Access Point (WAP) over the mesh netwo ...

WinMee2008

Interference management in impulse-radio ultra-wide band networks

Ruben Merz

We consider networks of impulse-radio ultra-wide band (IR-UWB) devices. We are interested in the architecture, design, and performance evaluation of these networks in a low data-rate, self-organized, and multi-hop setting. IR-UWB is a potential physical la ...

EPFL2008

Modeling the 802.11 protocol under different capture and sensing capabilities

Patrick Thiran, Olivier Dousse, Mathilde Durvy

Decentralized medium access control schemes for wireless networks based on CSMA/CA, such as the 802.11 protocol, are known to be unfair. In multi-hop networks, they can even favor some connections to such an extent that the others suffer from virtually com ...

2007