Publications associées à Channel access method

Topological MIMO Optical Signal Processing

Romain Christophe Rémy Fleury, Farzad Zangeneh Nejad

An important advantage of optical signal processing is the possibility of performing various operations in parallel. Among the techniques proposed for parallel optical signal processing, frequency division multiplexing (FDM) is a well-known approach, in wh ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Efficient Concurrent Analytical Query Processing using Data and Workload-conscious Sharing

Panagiotis Sioulas

Analytical workloads are evolving as the number of users surges and applications that submit queries in batches become popular. However, traditional analytical databases that optimize-then-execute each query individually struggle to provide timely response ...

EPFL2023

Parallel temporal signal processing enabled by polarization-multiplexed programmable THz metasurfaces

Romain Christophe Rémy Fleury, Ali Momeni

Under the trends of multifunctionality, tunability, and compactness in modern wave -based signal processors, in this paper, we propose a polarization-multiplexed graphene-based metasurface to realize distinct mathematical operators on the parallel time-dom ...

Optica Publishing Group2022

Beam Selection and Tracking for Amplify-and-Forward Repeaters

Andreas Peter Burg, Ruben Merz, Adrian Schumacher

Mobile network operators constantly have to upgrade their cellular network to satisfy the public's hunger for increasing data capacity. However, regulatory limits regarding allowed electromagnetic field strength on existing cell sites often limit or preven ...

IEEE2022

Cellular Fronthauling for Data Capacity Increase in Underserved Spaces

Adrian Schumacher

The increase in wireless data traffic continues and is a product of several factors. First, new technologies and capabilities enable new use cases for which new products emerge. Then, with the growing user adoption over time, the data traffic is further in ...

EPFL2022

N-coordinated bimetallic defect-rich nanocarbons as highly efficient electrocatalysts in advanced energy conversion applications

Ulf Anders Hagfeldt, Sining Yun

Defect engineering in heterostructured carbon-based electrode materials has evolved as an emerging strategy to boost the electrocatalytic activity. Herein, a facile single-step route is reported to synthesize novel N-coordinated bimetal doped graphitic car ...

ELSEVIER SCIENCE SA2022

Experimental demonstration of dynamic spatiotemporal structured beams that simultaneously exhibit two orbital angular momenta by combining multiple frequency lines, each carrying multiple Laguerre-Gaussian modes

Tobias Kippenberg, Maxim Karpov, Zhe Zhao, Hao Song, Xinzhou Su

In general, there are different, relatively independent forms of orbital angular momenta at a given propagation distance, which might exhibit different dynamic spatial characteristics. One type involves a beam with a helical phase-front that rotates around ...

Optica Publishing Group2022

Over-the-Air Computation via Reconfigurable Intelligent Surface

Yuning Jiang, Wei Chen

Over-the-air computation (AirComp) is a disruptive technique for fast wireless data aggregation in Internet of Things (IoT) networks via exploiting the waveform superposition property of multiple-access channels. However, the performance of AirComp is bott ...

2021

Federated Learning Over Wireless Networks: Convergence Analysis and Resource Allocation

Vincent Gramoli

There is an increasing interest in a fast-growing machine learning technique called Federated Learning (FL), in which the model training is distributed over mobile user equipment (UEs), exploiting UEs' local computation and training data. Despite its advan ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2021

Cross Modal Focal Loss for RGBD Face Anti-Spoofing

Sébastien Marcel

Automatic methods for detecting presentation attacks are essential to ensure the reliable use of facial recognition technology. Most of the methods available in the litera- ture for presentation attack detection (PAD) fails in gen- eralizing to unseen atta ...

IEEE2021

A Maximum-Likelihood-based Multi-User LoRa Receiver Implemented in GNU Radio

Andreas Peter Burg, Alexios Konstantinos Balatsoukas Stimming, Orion Afisiadis, Joachim Tobias Tapparel, Mathieu Pierre Xhonneux

LoRa is a popular low-power wide-area network (LPWAN) technology that uses spread-spectrum to achieve long-range connectivity and resilience to noise and interference. For energy efficiency reasons, LoRa adopts a pure ALOHA access scheme, which leads to re ...

IEEE2020

Sampling and Reconstruction of Bandlimited Signals with Multi-Channel Time Encoding

Martin Vetterli, Karen Adam, Adam James Scholefield

Sampling is classically performed by recording the amplitude of the input at given time instants; however, sampling and reconstructing a signal using multiple devices in parallel becomes a more difficult problem to solve when the devices have an unknown sh ...

2020

Multi-Channel AlGaN/GaN In-Plane-Gate Field-Effect Transistors

Elison de Nazareth Matioli, Jun Ma, Catherine Erine, Giovanni Santoruvo

In this letter, we present a multi-channel in-plane-gate field effect transistor (MC-IPGFET). In the proposed device, multiple vertically stacked two-dimensional electron gases (2DEGs) are simultaneously controlled by lateral in-plane gates formed with the ...

Institute of Electrical and Electronics Engineers2020

Kramers Kronig detection of four 20 Gbaud 16-QAM channels using Kerr combs for a shared phase estimation

Tobias Kippenberg, Maxim Karpov, Martin Hubert Peter Pfeiffer, Arne Kordts, Fatemeh Alishahi, Ahmad Fallahpour

We experimentally demonstrate Kramers-Kronig detection of four 20 Gbaud 16-quadrature-amplitude-modulated (QAM) channels after 50 km fiber transmission using two soliton Kerr combs as signal sources and local oscillators. The estimated carrier phase at the ...

OPTICAL SOC AMER2020

Hardware Implementation of Neural Self-Interference Cancellation

Andreas Peter Burg, Alexios Konstantinos Balatsoukas Stimming, Andreas Toftegaard Kristensen, Yann Kurzo

In-band full-duplex systems can transmit and receive information simultaneously and on the same frequency band. However, due to the strong self-interference caused by the transmitter to its own receiver, the use of non-linear digital self-interference canc ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

Dual Connectivity-Based Mobility Management and Data Split Mechanism in 4G/5G Cellular Networks

Mohammad Khaja Nazeeruddin

The emerging 5G mobile network technology is envisioned to provide an efficient platform to interconnect machines, objects, and devices in addition to interconnecting people. Equipped with peak data rates, low latency, and massive capacity, 5G technology w ...

2020

Demonstration of Tunable Optical Aggregation of QPSK to 16-QAM Over Optically Generated Nyquist Pulse Trains Using Nonlinear Wave Mixing and a Kerr Frequency Comb

Tobias Kippenberg, Maxim Karpov, Martin Hubert Peter Pfeiffer, Arne Kordts, Fatemeh Alishahi, Ahmad Fallahpour, Cong Liu

A tunable and reconfigurable optical aggregation system is experimentally demonstrated. Optical Nyquist pulses are generated on multiple channels using a microresonator-based Kerr optical frequency comb and insertion of uniform lines by an intensity modula ...

IEEE Institute of Electrical and Electronics Engineers2020

On the Implementation Complexity of Digital Full-Duplex Self-Interference Cancellation

Andreas Peter Burg, Alexios Konstantinos Balatsoukas Stimming, Andreas Toftegaard Kristensen

In-band full-duplex systems promise to further increase the throughput of wireless systems, by simultaneously transmitting and receiving on the same frequency band. However, concurrent transmission generates a strong self-interference signal at the receive ...

IEEE2020

Compute-Forward for DMCs: Simultaneous Decoding of Multiple Combinations

Michael Christoph Gastpar, Sung Hoon Lim, Adriano Pastore, Chen Feng

Algebraic network information theory is an emerging facet of network information theory, studying the achievable rates of random code ensembles that have algebraic structure, such as random linear codes. A distinguishing feature is that linear combinations ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

Physical Layer Aspects of LoRa and Full-Duplex Wireless Transceivers

Orion Afisiadis

Wireless communications are currently faced with two main challenges. The first challenge stems from the enormous number of Internet of Things (IoT) devices that transmit very small amounts of data. The second challenge is the need for ever-increasing data ...

EPFL2020