LoRaMoto: a LoRa-based communication system for coordinated response in an earthquake aftermath (excerpt)

Response of emergency units after natural disasters, such as earthquakes, has to be coordinated, fast and efficient in order to rescue and care for the victims, keeping all the population –and the units themselves– safe amidst the chaos. Outages in mobile networks, as well as fiber- or copper-based landline and Internet connections are to be expected in such situations, so alternative communication solutions must be considered. To contribute in this duty, we propose a communication system that uses the LoRaWAN architecture to allow citizens to report their status to emergency units and public authorities with simple messages and interaction mechanisms. To analyse the system performance and capabilities we model a district of Coquimbo, a harbour town in Chile, that houses approximately 28.000 people in 7.500 homes, and simulate it with a baseline configuration. We explore several modifications of the system in order to determine its characteristics and limitations, to better understand its scalability and portability to other environments, and to outline the remaining challenges to make the system attain to specific performance guaranteesPreprin

Towards LoRa mesh networks for the IoT

There are several LPWAN radio technologies providing wireless communication to the billions of connected devices that form the so-called IoT. Among them, LoRa has emerged in recent years as a popular solution for low power embedded devices to transmit data at long distances on a reduced energy budget. Most often, LoRa is used as the physical layer of LoRaWAN, an open standard that defines a MAC layer and specifies the star-of-stars topology, operation, roles and mechanisms for an integrated, full-stack IoT architecture. Nowadays, millions of devices use LoRaWAN networks in all sorts of agriculture, smart cities and buildings, industry, logistics and utilities scenarios. Despite its success in all sorts of IoT domains and environments, there are still use cases that would benefit from more flexible network topologies than LoRaWAN's star-of-stars. For instance, in scenarios where the deployment and operation of the backbone network infrastructure is technically or economically challenging, a more flexible model may improve certain performance metrics. As a first major contribution, this thesis investigates the effects of adding multi-hop capability to LoRaWAN, by means of the realistic use case of a communication system based on this architecture that provides a coordinated response in the aftermath of natural disasters like an earthquake. The capacity of end nodes to forward packets and perform multi-hop transmissions is explored, as a strategy to overcome gateway infrastructure failures, and analyzed for challenges, benefits and drawbacks in a massive system with thousands of devices. LoRa is also used as a stand-alone radio technology, independently from the LoRaWAN architecture. Its CSS modulation offers many advantages in LPWANs for IoT deployments. In particular, its different SFs available determine a trade-off between transmission time (i.e., data rate) and sensitivity (i.e., distance reach), and also generate quasi-orthogonal signals that can be demodulated concurrently by different receivers. The second major contribution of this thesis is the design of a minimalistic distance-vector routing protocol for embedded IoT devices featuring a LoRa transceiver, and the proposal of a path cost calculation metric that takes advantage of the multi-SF capability to reduce end-to-end transmission time. The protocol is evaluated through simulation and compared with other well-known routing strategies, analyzing and discussing its suitability for heterogeneous IoT LoRa mesh networks.Hi ha diverses tecnologies de ràdio LPWAN que proporcionen comunicació sense fils als milers de milions de dispositius connectats que conformen l'anomenada IoT. D'entre elles, LoRa ha emergit en els darrers anys com una solució popular per a què dispositius encastats amb pocs recursos transmetin dades a llargues distàncies amb un cost energètic reduït. Tot sovint, LoRa s'empra com la capa física de LoRaWAN, un estàndard obert que defineix una capa MAC i que especifica la topologia en estrella d'estrelles, l'operació, els rols i els mecanismes per implementar una arquitectura de la IoT integrada. A dia d'avui, milions de dispositius fan servir xarxes LoRaWAN en escenaris d'agricultura, edificis i ciutats intel·ligents, indústria, logística i subministraments. Malgrat el seu èxit en tot tipus d'entorns i àmbits de la IoT, encara romanen casos d'ús que es beneficiarien de topologies de xarxa més flexibles que l'estrella d'estrelles de LoRaWAN. Per exemple, en escenaris on el desplegament i l'operació de la infraestructura troncal de xarxa és tècnicament o econòmica inviable, una topologia més flexible podria millorar certs aspectes del rendiment. Com a primera contribució principal, en aquesta tesi s'investiguen els efectes d'afegir capacitat de transmissió multi-salt a LoRaWAN, mitjançant el cas d'ús realista d'un sistema de comunicació, basat en aquesta arquitectura, per proporcionar una resposta coordinada en els moments posteriors a desastres naturals, tals com un terratrèmol. En concret, s'explora l'estratègia d'afegir la capacitat de reenviar paquets als nodes finals per tal d'eludir les fallades en la infraestructura, i se n'analitzen els reptes, beneficis i inconvenients per a un sistema massiu amb milers de dispositius LoRa s'empra també com a tecnologia de ràdio de forma autònoma, independentment de l'arquitectura LoRaWAN. La seva modulació CSS li confereix molts avantatges en xarxes LPWAN per a desplegaments de la IoT. En particular, els diferents SFs disponibles hi determinen un compromís entre la durada de les transmissions (i.e., la taxa de dades) i la sensibilitat en la recepció (i.e., l'abast en distància), alhora que generen senyals quasi-ortogonals que poden ser desmodulades de forma concurrent per receptors diferents. La segona contribució principal d'aquesta tesi és el disseny d'un protocol d'encaminament dinàmic vector-distància per a dispositius de la IoT encastats amb un transceptor LoRa, i la proposta d'una mètrica per calcular el cost d'un camí que aprofita la capacitat multi-SF per minimitzar el temps de transmissió d'extrem a extrem. El protocol és avaluat mitjançant simulacions i comparat amb altres estratègies d'encaminament conegudes, analitzant la seva conveniència per a xarxes LoRa mallades per a la IoT.Existen varias tecnologías de radio LPWAN que proporcionan comunicación inalámbrica a los miles de millones de dispositivos conectados que forman el llamado IoT. De entre ellas, LoRa ha emergido en los últimos años como una solución popular para que dispositivos embebidos con pocos recursos transmitan datos a largas distancias con un coste energético reducido. Habitualmente, LoRa se usa como la capa física de LoRaWAN, un estándar abierto que define una capa MAC y que especi_ca la topología en estrella de estrellas, la operación, los roles y los mecanismos para implantar una arquitectura del IoT integrada. A día de hoy, millones de dispositivos utilizan redes LoRaWAN en escenarios de agricultura, edificios y ciudades inteligentes, industria, logística y suministros. A pesar de su éxito en todo tipo de entornos y ámbitos del IoT, existen casos de uso que se beneficiaran de topologías de red más flexibles que la estrella de estrellas de LoRaWAN. Por ejemplo, en escenarios en los que el despliegue y la operación de la infraestructura troncal de red es técnica o económicamente inviable, una topología más flexible podrá mejorar ciertos aspectos del rendimiento. Como primera contribución principal, en esta tesis se investigan los efectos de añadir capacidad de transmisión multi-salto a LoRaWAN, mediante el caso de uso realista de un sistema de comunicación basado en dicha arquitectura, para proporcionar una respuesta coordinada en los momentos posteriores a desastres naturales, tales como un terremoto. En concreto, se explora la estrategia de añadir la capacidad de reenviar paquetes a los nodos finales para sortear las fallas en la infraestructura, y se analizan los retos, beneficios e inconvenientes para un sistema masivo con miles de dispositivos. LoRa se usa también como tecnología de radio de forma autónoma, independientemente de la arquitectura LoRaWAN. Su modulación CSS le confiere muchas ventajas en redes LPWAN para despliegues de IoT. En particular, los distintos SFs disponibles determinan un compromiso entre la duración de las transmisiones (i.e., la tasa de datos) y la sensibilidad en la recepción (i.e., el alcance en distancia), a la vez que generan señales cuasi-ortogonales que pueden ser desmoduladas de forma concurrente por receptores distintos. En segundo lugar, esta tesis contiene el diseño de un protocolo de enrutamiento dinámico vector-distancia para dispositivos Internet of Things (IoT) embebidos con un transceptor LoRa, y propone una métrica para calcular el coste de un camino que aprovecha la capacidad multi-SF para minimizar el tiempo de transmisión de extremo a extremo. El protocolo es evaluado y comparado con otras estrategias de enrutamiento conocidas, analizando su conveniencia para redes LoRa malladas para el IoT.Postprint (published version

Études des systèmes de communications sans-fil dans un environnement rural difficile

Les systèmes de communication sans fil, ayant de nombreux avantages pour les zones rurales, peuvent aider la population à bien s'y établir au lieu de déménager vers les centres urbains, accentuant ainsi les problèmes d’embouteillage, de pollution et d’habitation. Pour une planification et un déploiement efficace de ces systèmes, l'atténuation du signal radio et la réussite des liens d’accès doivent être envisagées. Ce travail s’intéresse à la provision d’accès Internet sans fil dans le contexte rural canadien caractérisé par sa végétation dense et ses variations climatiques extrêmes vu que les solutions existantes sont plus concentrées sur les zones urbaines. Pour cela, nous étudions plusieurs cas d’environnements difficiles affectant les performances des systèmes de communication. Ensuite, nous comparons les systèmes de communication sans fil les plus connus. Le réseau sans fil fixe utilisant le Wi-Fi ayant l’option de longue portée est choisi pour fournir les communications aux zones rurales. De plus, nous évaluons l'atténuation du signal radio, car les modèles existants sont conçus, en majorité, pour les technologies mobiles en zones urbaines. Puis, nous concevons un nouveau modèle empirique pour les pertes de propagation. Des approches utilisant l’apprentissage automatique sont ensuite proposées, afin de prédire le succès des liens sans fil, d’optimiser le choix des points d'accès et d’établir les limites de validité des paramètres des liens sans fil fiables. Les solutions proposées font preuve de précision (jusqu’à 94 % et 8 dB RMSE) et de simplicité, tout en considérant une multitude de paramètres difficiles à prendre en compte tous ensemble avec les solutions classiques existantes. Les approches proposées requièrent des données fiables qui sont généralement difficiles à acquérir. Dans notre cas, les données de DIGICOM, un fournisseur Internet sans fil en zone rurale canadien, sont utilisées. Wireless communication systems have many advantages for rural areas, as they can help people settle comfortably and conveniently in these regions instead of relocating to urban centers causing various overcrowding, habitation, and pollution problems. For effective planning and deployment of these technologies, the attenuation of the radio signal and the success of radio links must be precisely predicted. This work examines the provision of wireless internet access in the Canadian rural context, characterized by its dense vegetation and its extreme climatic variations, since existing solutions are more focused on urban areas. Hence, we study several cases of difficult environments affecting the performances of communication systems. Then, we compare the best-known wireless communication systems. The fixed wireless network using Wi-Fi, having the long-range option, is chosen to provide wireless access to rural areas. Moreover, we evaluate the attenuation of the radio signal, since the existing path loss models are generally designed for mobile technologies in urban areas. Then, we design a new path loss empirical model. Several approaches are then proposed by using machine learning to predict the success of wireless links, optimize the choice of access points and establish the validity limits for the pertinent parameters of reliable wireless connections. The proposed solutions are characterized by their accuracy (up to 94% and 8 dB RMSE) and simplicity while considering a wide range of parameters that are difficult to consider all together with conventional solutions. These approaches require reliable data, which is generally difficult to acquire. In our case, the dataset from DIGICOM, a rural Canadian wireless internet service provider, is used

Digital sustainability and entrepreneurship: How digital innovations are helping tackle climate change and sustainable development

Ministry of Education, Singapore under its Academic Research Funding Tier

The Alumni Network, Summer 2006 (Vol. XIX No. 1)

https://nsuworks.nova.edu/alumni_newsletter/1057/thumbnail.jp

The Observer

Student newspaper for Central Washington University for February 18-24, 2010. Vol. 84, No. 6.https://digitalcommons.cwu.edu/cwu_student_newspaper/5535/thumbnail.jp

Report of the Conference of Ministers of Agriculture of the Americas 2021 – Twenty-first Regular Meeting of the Inter-American Board of Agriculture

The Conference of Ministers of Agriculture of the Americas 2021 - Twenty-First Regular Meeting of the Inter-American Board of Agriculture (IABA) was held by virtual means, given the international conditions caused by the COVID-19 pandemic, on 1 and September 2, 2021. The Heads of Delegation of the IICA Member States present elected Ms. Tereza Cristina Corrêa da Costa Días, Minister of Agriculture, Livestock and Supply of Brazil as President of the IABA, and Mr. José Abelardo Mai, Minister of Agriculture, Food Security and Business of Belize as rapporteur of the meeting. The ministerial meeting was opened by the President of the Republic of Costa Rica, Mr. Carlos Alvarado. During this meeting, Mr. Manuel Otero was unanimously re-elected as Director General of IICA for the period 2022-2026; The facilities of the Interpretation Center of Tomorrow for Agriculture (CIMAG) were also inaugurated. The Conference of Ministers of Agriculture of the Americas dealt with "Sustainable Agrifood Systems, Engine of Development of the Americas" and was attended by senior officials from the United Nations (UN) and FAO. Likewise, a ministerial dialogue was held on the situation of African swine fever and its possible effects on the member countries of the Institute. The Inter-American Board of Agriculture received the report of the Director General of IICA on its management in the period 2018-2022; witnessed the delivery of awards to the Leaders of Rurality, as well as the signing of the agreement with the Green Climate Fund (FVC); Likewise, he learned about the report “Perspectives for agriculture and rural development in the Americas: a look at Latin America and the Caribbean”; approved the program budget 2022-2023; and approved the new Statutes of the Inter-American Commission on Organic Agriculture (ICOA), among other matters of relevance to the institutional life of the organization