Publications associées à Cooperative diversity

Improving Throughput, Latency and Privacy with Hybrid Networks and Multipath Routing

Over the last few years, residential and enterprise networking have faced several challenges due to the increasing demand of users for high-throughput connectivity. As a result, efforts are being made to improve coverage, throughput, and robustness. Severa ...

EPFL2018

Diversity Gain Influenced by Polarization and Spatial Diversity Techniques in Ultrawideband

Anja Skrivervik, Mohsen Koohestani

This paper presents an experimental investigation of diversity gain influenced by polarization and spatial diversity techniques in ultrawideband (UWB) radio technology. To this aim, two different coplanar-fed UWB diversity antennas having the same size and ...

2015

On lattice codes for Gaussian interference channels

Michael Christoph Gastpar, Jingge Zhu

The usefulness of lattice codes is investigated for two-user Gaussian interference channels (IC). A coding scheme based on the compute-and-forward technique is shown to achieve the capacity region of the Gaussian IC under strong interference. The proposed ...

2015

Reconfigurable Antennas for Beam-Space MIMO Transmission with a Single Radio

Mohsen Yousefbeiki

MIMO techniques allow remarkable improvements in the reliability and/or transmission rate of wireless communication systems. However, there are several major challenges towards the implementation of conventional MIMO concept in terminals with size, cost, a ...

EPFL2015

Approximate Ergodic Capacity of a Class of Fading Two-User Two-Hop Networks

Michael Christoph Gastpar, Chien-Yi Wang

The fading AWGN two-user two-hop network is considered where the channel coefficients are independent and identically distributed (i.i.d.) according to a continuous distribution and vary over time. For a broad class of channel distributions, the ergodic su ...

Institute of Electrical and Electronics Engineers2014

Cooperative Relaying at Finite SNR-Role of Quantize-Map-and-Forward

Christina Fragouli, Ayan Sengupta, I-Hsiang Wang

This paper contributes to the design and analysis of Quantize-Map-and-Forward (QMF) relaying by optimizing its performance for small relay networks. QMF was proved to achieve the capacity of arbitrary networks within a bounded gap, as well as the optimal d ...

Ieee-Inst Electrical Electronics Engineers Inc2014

Orthomode transducer for dual polarized substrate integrated circuits and antennas

Juan Ramon Mosig, Michael Mattes, Marc Esquius Morote

A complete dual polarized substrate integrated structure is presented. It comprises planar excitation schemes for both orthogonal TE10 and TE01 modes along with an orthomode transducer (OMT) to combine/split them. The whole structure is compact (only 2 lay ...

2014

Wireless Neurosensor for Full-Spectrum Electrophysiology Recordings during Free Behavior

Grégoire Courtine, Hao Li, David Allenson Borton, Yao Lu, Jean François Pierre Laurens

Brain recordings in large animal models and humans typically rely on a tethered connection, which has restricted the spectrum of accessible experimental and clinical applications. To overcome this limitation, we have engineered a compact, lightweight, high ...

Cell Press2014

Optimizing Quantize-Map-and-Forward in Slow Fading Relay Networks

Christina Fragouli, Ayan Sengupta, I-Hsiang Wang

Quantize-Map-and-Forward (QMF) relaying has been shown to achieve the optimal diversity-multiplexing trade-off (DMT) for the slow fading single-antenna relay channel, regardless of whether the relay is full-duplex or half-duplex. A key reason for the DMT o ...

Ieee2013

Approximate Ergodic Capacity of a Class of Fading 2-user 2-hop Networks

Michael Christoph Gastpar, Chien-Yi Wang

We consider a fading AWGN 2-user 2-hop network in which the channel coefficients are independently and identically distributed (i.i.d.) drawn from a continuous distribution and vary over time. For a broad class of channel distributions, we characterize the ...

Ieee2012

Hierarchical Beamforming for Large One-Dimensional Wireless Networks

Olivier Lévêque, Alla Merzakreeva

We consider a wireless network with a large number of source-destination pairs distributed over a line. Under line-of-sight propagation, this network has only one degree of freedom for communication. At high SNR, this one degree of freedom can be readily a ...

Ieee2012

Prioritized Distributed Video Delivery with Randomized Network Coding

Pascal Frossard, Jakov Cakareski, Nikolaos Thomos

We address the problem of prioritized video streaming over lossy overlay networks. We propose to exploit network path diversity via a novel Randomized Network Coding (RNC) approach that provides unequal error protection (UEP) to the packets conveying the v ...

2011

Bringing Stability to Wireless Mesh Networks

Adel Aziz

Wireless mesh networks were designed as a mean to rapidly deliver large-scale communication capabilities without the support of any prior infrastructure. Among the different properties of mesh networks, the self-organizing feature is particularly interesti ...

EPFL2011

Approximation for Problems in Multi-User Information Theory

Soheil Mohajerzefreh

The main goal in network information theory is to identify fundamental limits of communication over networks, and design solutions which perform close to such limits. After several decades of effort, many important problems still do not have a characteriza ...

EPFL2010

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

Fundamental limits and optimal operation in large wireless networks

Ayfer Özgür Aydin

Wireless adhoc networks consist of users that want to communicate with each other over a shared wireless medium. The users have transmitting and receiving capabilities but there is no additional infrastructure for assisting communication. This is in contra ...

EPFL2009

On the mutual information and low-SNR capacity of memoryless noncoherent Rayleigh-fading channels

Ninoslav Marina

The memoryless noncoherent single-input-single-output (SISO) Rayleigh-fading channel is considered. Closed-form expressions are derived for the mutual information between the output and the input of this channel when the input magnitude distribution is dis ...

2008

Diversity-Multiplexing-Delay Tradeoff in Half-Duplex ARQ Relay Channels

Sanket Dusad, Tarik Tabet

In this paper, we present an efficient protocol for the delay-limited fading ARQ single relay half duplex channel. The source is using an ARQ retransmission protocol to send data to the relay and the destination. When the relay is able to decode, both the ...

2007

Wormhole-Based Anti-Jamming Techniques in Sensor Networks

Jean-Pierre Hubaux, Mario Cagalj, Srdan Capkun

Due to their very nature, wireless sensor networks are probably the category of wireless networks most vulnerable to “radio channel jamming”-based Denial-of-Service (DoS) attacks. An adversary can easily mask the events that the sensor network should detec ...

2007

Schemes and architectures for wireless ad hoc networks and cooperative communication

Tarik Tabet

The focus of this thesis is on the study of decentralized wireless multi-hop networks. We are particularly interested in establishing bounds on the traffic-carrying capabilities of wireless ad hoc networks and conditions on the scalability of such networks ...

EPFL2007