Publications related to Tornado code

Scenario optimization for the tokamak ramp-down phase in RAPTOR: A. Analysis and model validation on ASDEX Upgrade

Olivier Sauter, Federico Alberto Alfredo Felici, Simon Van Mulders, Cassandre Ekta Contré, Anna Teplukhina, Bernhard Sieglin

We discuss how the combination of experimental observations and rapid modeling has enabled to improve understanding of the tokamak ramp-down phase in ASDEX Upgrade. A series of dedicated experiments has been performed, to disentangle the effect of individu ...

Iop Publishing Ltd2024

Inter-discharge optimization for fast, reliable access to ASDEX Upgrade advanced tokamak scenario

Olivier Sauter, Federico Alberto Alfredo Felici, Simon Van Mulders, Cassandre Ekta Contré, Hartmut Zohm

Rapid inter-discharge simulation and optimization using the RAPTOR code have allowed the development of a reliable and reproducible early heating strategy for an advanced tokamak (AT) scenario on ASDEX Upgrade. Solving for electron heat and current diffusi ...

IOP Publishing Ltd2024

A Generalized Adjusted Min-Sum Decoder for 5G LDPC Codes: Algorithm and Implementation

Andreas Peter Burg, Alexios Konstantinos Balatsoukas Stimming, Yifei Shen, Yuqing Ren, Hassan Harb

5G New Radio (NR) has stringent demands on both performance and complexity for the design of low-density parity-check (LDPC) decoding algorithms and corresponding VLSI implementations. Furthermore, decoders must fully support the wide range of all 5G NR bl ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Analysis of the influence of errors in DNA-based image coding

Touradj Ebrahimi, Michela Testolina, Davi Nachtigall Lazzarotto

In the last decade, DNA has been increasingly investigated as an alternative medium for cold data storage, presenting several advantages over standard hard drives such as a higher density, longer lifespan and lower energy consumption. However, such coding ...

2023

Low Power LDPC Decoding by Reliable Voltage Down-Scaling

Andreas Peter Burg

Low-Density Parity-Check (LDPC) decoder is among the power hungry building blocks of wireless communication systems. Voltage scaling down to Near-Threshold (NT) voltages substantially improves energy efficiency, in theory up 10x. However, tuning the voltag ...

IEEE2023

Healing plasma current ramp-up by nitrogen seeding in the full tungsten environment of WEST

Olivier Sauter, Federico Alberto Alfredo Felici, Simon Van Mulders

Achieving a successful plasma current ramp-up in a full tungsten tokamak can be challenging due to the large core radiation (and resulting low core temperature) that can be faced with this heavy metallic impurity if its relative concentration is too high. ...

2022

Secret Key Generation Using Short Blocklength Polar Coding Over Wireless Channels

Yanina Yurina Shkel

This paper investigates the problem of secret key generation from correlated Gaussian random variables in the short blocklength regime. Short blocklengths are commonly employed in massively connected IoT sensor networks in 5G and beyond wireless systems. P ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Secret Key Generation Over Wireless Channels Using Short Blocklength Multilevel Source Polar Coding

Yanina Yurina Shkel

This paper investigates the problem of secret key generation from correlated Gaussian random variables in the short block-length regime. Inspired by the state-of-the-art performance provided by polar codes in the short blocklength regime for channel coding ...

IEEE2021

Design and Decoding of Irregular LDPC Codes Based on Discrete Message Passing

Andreas Peter Burg

We consider discrete message passing (MP) decoding of low-density parity check (LDPC) codes based on information-optimal symmetric look-up table (LUT). A link between discrete message labels and the associated log-likelihood ratio values (defined in terms ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

Compute–Forward Multiple Access (CFMA): Practical Implementations

Michael Christoph Gastpar, Sung Hoon Lim, Jingge Zhu, Erixhen Sula, Adriano Pastore

We present a practical strategy that aims to attain rate points on the dominant face of the multiple access channel capacity using a standard low complexity decoder. This technique is built upon recent theoretical developments of Zhu and Gastpar on compute ...

2019

New Results On The Pseudoredundancy

Jens Markus Zumbrägel, Zihui Liu

The concepts of pseudocodeword and pseudoweight play a fundamental role in the finite-length analysis of LDPC codes. The pseudoredundancy of a binary linear code is defined as the minimum number of rows in a parity-check matrix such that the corresponding ...

2019

From LDPC Block to LDPC Convolutional Codes: Capacity, Stability, and Universality

Wei Liu

In his landmark paper "A Mathematical Theory of Communication," the founding father of information theory and coding theory, Claude E. Shannon, established the largest rate at which reliable communication is possible and he revealed that the key to this re ...

EPFL2019

The Velocity of the Propagating Wave for Spatially Coupled Systems With Applications to LDPC Codes

Nicolas Macris, Rafah El-Khatib

We consider the dynamics of message passing for spatially coupled codes and, in particular, the set of density evolution equations that tracks the profile of decoding errors along the spatial direction of coupling. It is known that, for suitable boundary c ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2018

The Stability Condition of LDPC Codes Under MAP Decoding

Rüdiger Urbanke, Wei Liu

We determine the stability condition of low-density parity-check codes under both bitwise and blockwise maximum a posteriori decoding. As a consequence, we prove that the stability condition determines an upper bound on both the bitwise and the blockwise m ...

IEEE2018

Design of LDPC Codes for the Unequal Power Two-User Gaussian Multiple Access Channel

Alexios Konstantinos Balatsoukas Stimming

In this letter, we describe an LDPC code design framework for the unequal power two-user Gaussian multiple access channel using EXIT charts. We show that the sumrate of the LDPC codes designed using our approach can get close to the maximal sum-rate of the ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2018

Scaling and Resilience in Numerical Algorithms for Exascale Computing

Allan Svejstrup Nielsen

The first Petascale supercomputer, the IBM Roadrunner, went online in 2008. Ten years later, the community is now looking ahead to a new generation of Exascale machines. During the decade that has passed, several hundred Petascale capable machines have bee ...

EPFL2018

Simulation of profile evolution from ramp-up to ramp-down and optimization of tokamak plasma termination with the RAPTOR code

Olivier Sauter, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Doohyun Kim, Anna Teplukhina, Donghyun Kim

The present work demonstrates the capabilities of the transport code RAPTOR as a fast and reliable simulator of plasma profiles for the entire plasma discharge, i.e. from ramp-up to ramp-down. This code focuses, at this stage, on the simulation of electron ...

2017

Coding for Communications and Secrecy

Mani Bastaniparizi

Shannon, in his landmark 1948 paper, developed a framework for characterizing the fundamental limits of information transmission. Among other results, he showed that reliable communication over a channel is possible at any rate below its capacity. In 2008, ...

EPFL2017

Bit-flipping LDPC under noise conditions and its application to Physically Unclonable Functions

Alexandre Schmid, Takao Marukame

A low-density parity check (LDPC) circuit and its properties as a post-processor is proposed for physically unclonable functions (PUFs) applications. PUFs can be realized using process variations or signal noises in SRAM or other PUF circuits, whereas the ...

Ieee2016

Hardware Decoders for Polar Codes: An Overview

Andreas Peter Burg, Pascal Giard

Polar codes are an exciting new class of error correcting codes that achieve the symmetric capacity of memoryless channels. Many decoding algorithms were developed and implemented, addressing various application requirements: from error-correction performa ...

Ieee2016