Publications by Orion Afisiadis

A Low-Complexity LoRa Synchronization Algorithm Robust to Sampling Time Offsets

Orion Afisiadis, Mathieu Pierre Xhonneux

LoRaWAN is nowadays one of the most popular protocols for low-power Internet of Things communications. Although its physical layer, namely LoRa, has been thoroughly studied in the literature, aspects related to the synchronization of LoRa receivers have re ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

A Maximum-Likelihood-Based Two-User Receiver for LoRa Chirp Spread-Spectrum Modulation

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

Long Range (LoRa) is an emerging low-power wide-area network technology offering long-range wireless connectivity to Internet of Things (IoT) devices. For energy efficiency reasons, LoRa end nodes implement a nonslotted ALOHA multiple access scheme to tran ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

On the Advantage of Coherent LoRa Detection in the Presence of Interference

Andreas Peter Burg, Alexios Konstantinos Balatsoukas Stimming, Orion Afisiadis, Joachim Tobias Tapparel, Sitian Li

It has been shown that the coherent detection of long range (LoRa) signals only provides marginal gains of around 0.7 dB on the additive white Gaussian noise (AWGN) channel. However, ALOHA-based massive Internet-of-Things systems, including LoRa, often ope ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2021

On the Error Rate of the LoRa Modulation With Interference

Andreas Peter Burg, Alexios Konstantinos Balatsoukas Stimming, Orion Afisiadis, Matthieu Cotting

LoRa is a chirp spread-spectrum modulation developed for the Internet of Things (IoT). In this work, we examine the performance of LoRa in the presence of both additive white Gaussian noise and interference from another LoRa user. To this end, we extend an ...

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

An Open-Source LoRa Physical Layer Prototype on GNU Radio

Andreas Peter Burg, Alexios Konstantinos Balatsoukas Stimming, Orion Afisiadis, Joachim Tobias Tapparel, Paul Angelin Antoine Mayoraz

LoRa is the proprietary physical layer (PHY) of LoRaWAN, which is a popular Internet-of-Things (IoT) protocol enabling low-power devices to communicate over long ranges. A number of reverse engineering attempts have been published in the last few years tha ...

IEEE2020

Coded LoRa Frame Error Rate Analysis

Andreas Peter Burg, Alexios Konstantinos Balatsoukas Stimming, Orion Afisiadis

In this work, we study the coded frame error rate (FER) of LoRa under additive white Gaussian noise (AWGN) and under carrier frequency offset (CFO). To this end, we use existing approximations for the bit error rate (BER) of the LoRa modulation under AWGN ...

IEEE2020

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

Lora Digital Receiver Analysis And Implementation

Andreas Peter Burg, Orion Afisiadis, Reza Ghanaatian Jahromi, Matthieu Cotting

Low power wide area network technologies (LPWANs) are attracting attention because they fulfill the need for long range low power communication for the Internet of Things. LoRa is one of the proprietary LPWAN physical layer (PHY) technologies, which provid ...

IEEE2019

LoRa Symbol Error Rate Under Non-Aligned Interference

Andreas Peter Burg, Alexios Konstantinos Balatsoukas Stimming, Orion Afisiadis, Matthieu Cotting

In this work, we examine the performance of the LoRa chirp spread spectrum modulation in the presence of both additive white Gaussian noise and interference from another LoRa user. To this end, we extend an existing interference model to the more realistic ...

IEEE2019