Multi-channel Distributed MAC protocol for WSN-based wildlife monitoring

International audienceSeveral wild animal species are endangered by poaching. As a solution, deploying wireless sensors on animals able to send regular messages and also alert messages has been envisaged recently by several authorities and foundations. In that context, this paper proposes WildMAC, a multichannel, multihop wireless communication protocol for these specific wireless sensor networks that have to collect data from unknown large areas with different QoS requirements. WildMAC is a TDMA based MAC protocol that leverages long range communication properties to propose an efficient data collection mean. Its performance evaluation shows it meets QoS requirements

A Thompson Sampling Approach to Channel Exploration-Exploitation Problem in Multihop Cognitive Radio Networks

International audienceCognitive radio technology is a promising solution to the exponential growth in bandwidth demand sustained by increasing number of ubiquitous connected devices. The allocated spectrum is opened to the secondary users conditioned on limited interference on the primary owner of the band. A major bottleneck in cognitive radio systems is to find the best available channel quickly from a large accessible set of channels. This work formulates the channel exploration-exploitation dilemma as a multi-arm bandit problem. Existing theoretical solutions to a multi-arm bandit are adapted for cognitive radio and evaluated in an experimental test-bed. It is shown that a Thompson sampling based algorithm efficiently converges to the best channel faster than the existing algorithms and achieves higher asymptotic average throughput. We then propose a multihop extension together with an experimental proof of concept

From Outage Probability to ALOHA MAC Layer Performance Analysis in Distributed WSNs

International audienceIn this paper we develop an explicit formula of outage probability in a distributed wireless sensor network (WSN), assuming the MAC layer protocol being a slotted-ALOHA. And adopting a Markovian approach, we develop a model that analyses the performance of the slotted-ALOHA in order to improve these performances, in particular, by adding a preliminary stage of channel reservation, we show that this modification is important to have a high performance distributed wireless sensor network

Competition: Channel Exploration/Exploitation Based on a Thompson Sampling Approach in a Radio Cognitive Environment

International audienceMachine learning approaches have been extensively applied in interference mitigation and cognitive radio devices. In this work, we model the spectrum selection process as a multi-arm bandit problem and apply Thompson sampling, a fast and efficient algorithm, to find the best channel in the shortest time interval. The learning algorithm will work on top of a network layer to efficiently route the event information to the sink

Everlasting sensor networks

Poster for " L'énergie demain. Transition énergétique : recherches et ingénierie " symposium. May 30-31, 2013, MINES ParisTechWithin the team CSAM (Circuits, Systèmes et Applications des Microondes) of IEMN (Institut d'Électronique, de Microélectronique et de Nanotechnologie) and within IRCICA (Institut de Recherche sur les Composants logiciels et matériels pour l'Information et la Communication Avancée - USR CNRS 3080) we develop a research on ultra low power sensor networks. Our goal is to minimize the energy consumption so that the life duration of the network could be infinitely long. We develop studies including nanotechnologies (energy harvesting, storage devices), RF front-ends design, energy management but also radio channel and interference modeling and MAC layer optimization

Couche MAC adaptative pour réseaux de capteurs limités par l’interférence

In the era of the Internet of Things, the number of connected devices is growing dramatically. Often, connected objects use Industrial, Scientific and Medical radio bands for communication. These kinds of bands are available without license, which facilitates development and implementation of new connected objects. However, it also leads to an increased level of interference in these bands. Interference not only negatively affects the Quality of Service, but also causes energy losses, which is especially unfavorable for the energy constrained Wireless Sensor Networks (WSN). In the present thesis the impact of the interference on the energy consumption of the WSN nodes is studied experimentally. The experimental results were used to estimate the lifetime of WSN nodes under conditions of different levels of interference. Then, a Thompson sampling based Cognitive Radio (CR) adaptive solution is proposed and evaluated via both, simulation and hardware implementation. Results show that this approach finds the best channel quicker than other state of the art solutions. An extension for multihop WSN was proposed for this CR solution and evaluated by hardware implementation in the framework of EWSN Dependability Competition. Finally, an adaptive WildMAC MAC layer protocol is proposed for the usecase of the LIRIMA PREDNET wildlife animal tracking project. Obtained field range test data were used to theoretically estimate cell densities and deployment zone coverage in this Low Power Widea Area Network (LPWAN). Then performance of the protocol was evaluated in WSNet simulation. The results show performance that allows to respect PREDNET project requirements with the given coverage.A l'époque de l'Internet des Objets, le nombre de dispositifs communicants ne cesse d'augmenter. Souvent, les objets connectés utilisent des bandes de fréquences « industriel, scientifique et médical (ISM) » pour effectuer les communications. Ces bandes sont disponibles sans licence, ce qui facilite le déploiement de nouveaux objets connectés. Cependant, cela mène aussi au fait que le niveau d'interférences augmente dans les bandes ISM. Les interférences ont non seulement un impact négatif sur la qualité de service, mais aussi elles causent des pertes de messages couteuses en énergie, ce qui est particulièrement nocif pour les nœuds capteurs souvent limités en énergie. Dans cette thèse, l'impact des interférences sur la consommation énergétique des nœuds est étudié expérimentalement. Les résultats de ces expérimentations sont utilisés pour estimer la durée de vie des nœuds en fonction de différents niveaux d’interférence subis. Puis, un algorithme de Radio Cognitive (RC) basé sur la technique d’ échantillonnage de Thompson est proposé et évalué par la simulation et implémentation. Les résultats montrent que l'approche proposée trouve le meilleur canal plus vite que les autres techniques. De plus, une extension multi sauts pour RC est proposée et évaluée par expérimentation lors d'une compétition EWSN Dependability Competition. Finalement, le protocole adaptatif WildMAC est proposé pour le cas d'usage du projet LIRIMA PREDNET qui consiste à surveiller des animaux sauvages. Les performances sont évaluées par simulation avec le simulateur WSNet. Les résultats montrent que la solution proposée respecte les contraintes imposées par le projet PREDNET dans la zone ciblée

Multi-channel Distributed MAC protocol for WSN-based wildlife monitoring

International audienceSeveral wild animal species are endangered by poaching. As a solution, deploying wireless sensors on animals able to send regular messages and also alert messages has been envisaged recently by several authorities and foundations. In that context, this paper proposes WildMAC, a multichannel, multihop wireless communication protocol for these specific wireless sensor networks that have to collect data from unknown large areas with different QoS requirements. WildMAC is a TDMA based MAC protocol that leverages long range communication properties to propose an efficient data collection mean. Its performance evaluation shows it meets QoS requirements

Experimental Evaluation of Interference Impact on the Energy Consumption in Wireless Sensor Networks

International audienceIn the era of Internet of Things (IoT), the development of Wireless Sensor Networks (WSN) arises different challenges. Two of the main issues are electromagnetic interference and the lifetime of WSN nodes. In this paper, we show and evaluate experimentally the relation between interference and energy consumption, which impacts the network lifetime. We present a platform based on commercially available low-cost hardware in order to evaluate the impact of electromagnetic interference in 2.4 GHz ISM band on energy consumption of WSN. The energy measurements are obtained separately from each electronic component in the node. Interference and energy measurements are conducted in an anechoic chamber and in an office-type lab environment. X-MAC protocol is chosen to manage the Radio Duty Cycle of the nodes and its energy performance is evaluated. The energy consumption transmitter nodes is analyzed particularly in this work. Moreover, this energy consumption has been quantified and differentiated according to the number of (re-)transmissions carried out by the transmitter as well as the number of ACK packets sent by the receiver for a single packet. Finally, we use a model of real battery to calculate the lifetime of the node for operation within different interference level zones. This study lays the basis for further design rules of communication protocols and development of WSNs

Performance evaluation of LoRa radio solution for PREDNET wildlife animal tracking project

International audiencePerformance evaluation of LoRa radio solution is provided based on coverage simulations and range tests. The full version of abstract is attached