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.
During the last decade, the number of wireless devices like digital organizers, mobile phones and laptop computers has drastically increased. At the same time, several technologies, like Bluetooth, GPRS, or WiFi have become mature and offer a high-performa ...
Diversity embedded codes are opportunistic codes designed for the wireless fading channel. They are high-rate space-time codes which have embedded within them a high-diversity (low rate) code. In this paper, we focus on the application of diversity embedde ...
So far, the problem of positioning in wireless networks has been studied mainly in a nonadversarial setting. In this paper, we analyze the resistance of positioning techniques to position and distance spoofing attacks. We propose a mechanism for secure pos ...
We consider the design of the MAC layer for low power, low data-rate, impulse-radio ultra-wide band (IR-UWB) networks. In such networks, the primary concern is energy consumption rather than rate efficiency. We explore several dimensions such as power cont ...
The performance of multiband-OFDM UWB systems is analyzed using the S-V indoor channel model. Based on the analysis, two methods are proposed to improve the reliable transmission range of UWB devices by exploiting the rich spectral and spatial diversity av ...
We demonstrated high-speed photonic crystal nanocavity lasers with response time as short as similar to 2ps and direct modulation speeds exceeding 100GHz. Such high-speed characteristics are enabled by the use of cavity quantum electrodynamics effects such ...
Hearing aids are electronic, battery-operated sensing devices which aim at compensating various kinds of hearing impairments by means of appropriate signal processing. Most of today's hearing aid systems consist of two appliances working independently of e ...
We are interested in the design of physical layer (PHY) aware MAC for self-organized, low power, low data rate impulse-radio ultra-wideband (IR-UWB) networks. In such networks, energy consumption is much more of a concern than the achieved data rates. So f ...
We are interested in the design of physical-layer aware medium access control (PHY-aware MAC) for self-organized, low power, low data-rate impulse-radio ultra-wideband (IR-UWB) networks. In such networks, energy consumption is much more of a concern than a ...
In many networks, it is less costly to transmit a packet to any node in a set of neighbors than to one specific neighbor. A well-known instance is with unreliable wireless links, where the probability that at least one node out ofnreceives a packet increas ...
