Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.
AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.
Abstract—Rate and diversity impose a fundamental tradeoff in communications. This tradeoff was investigated for IntersymbolInterference (ISI) channels in [4]. A different point of view was explored in [1] where high-rate codes were designed so that they ha ...
Phase noise causes significant degradation in the performance of orthogonal frequency division multiplexing (OFDM)-based wireless communication systems. The presence of phase noise can reduce the effective signal-to-noise ratio (SNR) at the receiver, and c ...
The joint effects of IQ imbalance and phase noise on OFDM systems are analyzed, and a compensation scheme is proposed to improve the system performance. The scheme consists of a joint channel estimation algorithm and a joint data symbol estimation algorith ...
verlapping multipath propagation is one of the main sources of mobile-positioning errors, especially in fast channel fading situations. In this paper we present a technique for detecting the existence of overlapping fading multipath components. Such inform ...
OFDM systems are susceptible to receiver impairments such as IQ imbalance and phase noise. These impairments can severely degrade the achievable effective signal-to-noise ratio at the receiver. In this paper, we propose a joint compensation scheme to mitig ...
In handsfree tele- or video-communication, acoustic echoes arise due to the coupling between the loudspeakers and microphones. It is much more challenging to remove the undesired acoustic echoes for stereo or multi-channel tele-communication systems than f ...
This thesis is a study of the spatial evolution of the sound field. We first present an analysis of the sound field along different geometries. In the case of the sound field studied along a line in a room, we describe a two-dimensional function characteri ...
We evaluate the performance of an IEEE 802.15.4a ultra-wide band (UWB) physical layer, with an energy-detection receiver, in the presence of multi-user interference (MUI). A complete packet based system is considered. We take into account packet detection ...
This paper addresses the problem of efficiently delivering a layered media stream from multiple senders to a single receiver, over channels that present correlated packet loss patterns. Using a digital fountain approach, the performance of a distributed st ...
Wireless routing based on an embedding of the connectivity graph is a very promising technique to overcome shortcomings of geographic routing and topology-based routing. This is of particular interest when either absolute coordinates for geographic routing ...