Impact of on-body channel models on positioning success rate with UWB Wireless Body Area Networks

International audienceIn this paper, we aim to evaluate the positioning success rate of nodes placed on the body using different scheduling strategies at the Media Access Control (MAC) layer with Ultra Wide Band (UWB) Wireless Body Area Networks (WBAN) and under three different channel models. For this purpose, each node calculates its relative position with the estimation of its distances with the on-body anchors. Accordingly, the distance between two nodes can be estimated with the transmission of three packets, as defined by the '3-Way ranging' protocol (3-WR). However, these transactions can be affected by the WBAN channel leading into a packet loss and therefore positioning errors. In this work, we consider a PHY layer based on Impulse-Radio UWB (IR-UWB) with three different channels: (a) a theoretical path loss channel model based on the on-body CM3 channel (Anechoic chamber), (b) a simulated channel calculated with the PyLayers ray-tracing simulator and (c) experimental traces obtained by measurement. Moreover, we analyze the positioning success rate using three scheduling strategies (Single node localization (P2P), Broadcast Single node localiza-tion (P2P-B) and Aggregated & Broadcast (A&B)) with a MAC layer based on time division multiple access (TDMA) and under a realistic pedestrian walking scenario. Our results show that the scheduling strategy with A&B let the nodes to estimate more positions even through channels with slow and fast fading

Impact of Mobility on Ranging Estimation using UltraWideband

International audienceThis paper presents a study of the impact of mobility on the distance estimation between 2 nodes of a Wireless Body Area Network (WBAN) by comparing the Two-Way Ranging (2WR) and Three-Way Ranging (3WR) protocols. We consider a WBAN using a typical TDMA-based Medium Access Control (MAC) protocol and a IR-UWB physical layer defined by the standard IEEE802.15.6. We represent the impact by using the Root Mean Square Error (RMSE) in function of two types of parameters, the speed and the time of response. The results show that depending on the speed and the chosen reference point, it is better chose 2WR or 3WR if only mobility is considered. Finally, we propose to extend the study with a joint mobility and clock drift scenario with more sophisticated techniques such as cooperative scheduling algorithms or Aggregated and Broadcast mechanisms

Modélisation de l'impact de la vitesse des noeuds sur l'estimation des distances dans les Réseaux Corporels sans fils avec ULB

National audienceIn this paper, we aim to evaluate the impact of node speed on the positioning error with a Wireless Body Area Network (WBAN).In fact, the node position is estimated with the transmission of three packets defined by the protocol ’3-Way Ranging’. However, the distancebetween the sensors placed on the body can be affected by the human mobility. Thus, we study theoretically the distance estimation error withthe protocol ’3-Way Ranging’, based on a perfect channel, a TDMA MAC layer and a Physical layer based on Ultra Wide Band (as defined bythe standard IEEE 802.15.6). The results confirm that the distance and positioning error follows a big correlation with the node speed.– Le but de cet article est d'´ evaluer l'impact de la vitesse des noeuds sur l'erreur de positionnement dans les applications de localisation pour un réseau corporel sans fil. En effet, la distance de noeuds est estimée grâcè a l'envoi de trois paquets définis par le protocole '3-Way Ranging'. Cependant, la distance entre capteurs placés sur le corps peut etre impactée par les mouvements de la personne. Dans ce papier, nous commençons par examiner demanì ere théorique l'erreur d'estimation de distances avec le protocole '3-Way Ranging', en se basant sur un canal parfait, une couche MAC TDMA et une couche physique en Ultra Large Bande. Les résultats confirment que l'erreur sur les distances et positions est fortement corrélée avec la vitesse des noeuds. Abstract – In this paper, we aim to evaluate the impact of node speed on the positioning error with a Wireless Body Area Network (WBAN). In fact, the node position is estimated with the transmission of three packets defined by the protocol '3-Way Ranging'. However, the distance between the sensors placed on the body can be affected by the human mobility. Thus, we study theoretically the distance estimation error with the protocol '3-Way Ranging', based on a perfect channel, a TDMA MAC layer and a Physical layer based on Ultra Wide Band (as defined by the standard IEEE 802.15.6). The results confirm that the distance and positioning error follows a big correlation with the node speed

Modeling the impact of node speed on the ranging estimation with UWB body area networks

International audience—The purpose of this paper is to evaluate the impact of the node speed on the ranging estimation for location applications with Wireless Body Area Networks (WBAN). While estimated with the 3-Way ranging protocol (3-WR) , this distance between two nodes placed on the body can be affected by the human movements. Thus, we study theoretically the ranging error with the 3-WR, based on a perfect channel, a MAC layer based on TDMA using two scheduling strategies (Single node localization (P2P-B) and Aggregated & Broadcast (A&B)) and a PHY layer based on Ultra Wideband (IR-UWB). We demonstrate the accuracy of the model, and show that the distance error is highly correlated with the speed of nodes, while the associated mobility model has an impact on the design of MAC strategies by simulation

From the Characterization of Ranging Error to the Enhancement of Nodes Localization for Group of Wireless Body Area Networks

International audienceTime-based localization in Wireless Body Area Networks (WBANs), has attracted growing research interest for the last past years. Nodes positions can be estimated based on peer-to-peer radio transactions between devices. Indeed, the accuracy of the localization process could be highly affected by different factors , such as the WBAN channels where the signal is propagating through, as well as the nodes mobility that bias the peer-to-peer range estimation, and thus, the final achieved localization accuracy. The goal of this paper consists in characterizing the impact of mobility and WBAN channel on the ranging and localization estimation, based on real mobility traces acquired through a motion capture system. More specifically, the ranging error is evaluated over all the WBANs links (i.e. on-body, off-body and body-to-body links), while an impulse Radio Ultra-Wideband (IR-UWB) physical layer, as well as a TDMA-based Medium Access Control (MAC) are playing on. The simulation results show that the range measurement error can be modeled as a Gaussian distribution. To deal with the gaus-sianity observation of ranging error and to provide high positioning accuracy, an adjustable extended Kalman Filter (EKF) is proposed

Quantifying the impact of scheduling and mobility on IR-UWB localization in body area networks

International audience—In the context of radiolocation in Wireless Body Area Networks (WBANs), nodes positions can be estimated through time-based ranging algorithms. For instance, the distance separating a couple of nodes can be estimated accurately by measuring the Round Trip Time of Flight of an Impulse Radio Ultra Wideband (IR-UWB) link. This measure usually relies on two or three messages transactions. Such exchanges take time and a rapid mobility of the nodes can reduce the ranging accuracy and consequently impact nodes localization process. In this paper, we quantify this localization error by confronting two broadcast-based optimized implementations of the three-way ranging algorithm with real mobility traces, acquired through a motion capture system. We then evaluate, in the same scenarios, the impact of the MAC-level scheduling of the packets within a TDMA frame localization accuracy. The results, obtained with the WSNet simulator, show that MAC scheduling can be utilized to mitigate the effect of nodes mobility

The immunogenetic diversity of the HLA system in Mexico correlates with underlying population genetic structure

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) allele groups and alleles by PCR-SSP based typing in a total of 15,318 mixed ancestry Mexicans from all the states of the country divided into 78 sample sets, providing information regarding allelic and haplotypic frequencies and their linkage disequilibrium, as well as admixture estimates and genetic substructure. We identified the presence of 4268 unique HLA extended haplotypes across Mexico and find that the ten most frequent (HF > 1%) HLA haplotypes with significant linkage disequilibrium (Δ’≥0.1) in Mexico (accounting for 20% of the haplotypic diversity of the country) are of primarily Native American ancestry (A*02~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*08~DQB1*04, A*68~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*14~DQB1*03:01, A*24~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*04~DQB1*03:02, A*02~B*40:02~DRB1*04~DQB1*03:02, A*68~B*35~DRB1*04~DQB1*03:02, A*02~B*15:01~DRB1*04~DQB1*03:02). Admixture estimates obtained by a maximum likelihood method using HLA-A/-B/-DRB1 as genetic estimators revealed that the main genetic components in Mexico as a whole are Native American (ranging from 37.8% in the northern part of the country to 81.5% in the southeastern region) and European (ranging from 11.5% in the southeast to 62.6% in northern Mexico). African admixture ranged from 0.0 to 12.7% not following any specific pattern. We were able to detect three major immunogenetic clusters correlating with genetic diversity and differential admixture within Mexico: North, Central and Southeast, which is in accordance with previous reports using genome-wide data. Our findings provide insights into the population immunogenetic substructure of the whole country and add to the knowledge of mixed ancestry Latin American population genetics, important for disease association studies, detection of demographic signatures on population variation and improved allocation of public health resources.Fil: Barquera, Rodrigo. Max Planck Institute For The Science Of Human History; Alemania. Instituto Nacional de Antropología E Historia. Escuela Nacional de Antropología E Historia; MéxicoFil: Hernández Zaragoza, Diana Iraíz. Técnicas Genéticas Aplicadas A la Clínica (tgac); México. Instituto Nacional de Antropología E Historia. Escuela Nacional de Antropología E Historia; MéxicoFil: Bravo Acevedo, Alicia. Instituto Mexicano del Seguro Social; MéxicoFil: Arrieta Bolaños, Esteban. Universitat Essen; AlemaniaFil: Clayton, Stephen. Max Planck Institute For The Science Of Human History; AlemaniaFil: Acuña Alonzo, Víctor. Instituto Nacional de Antropología E Historia, Mexico; MéxicoFil: Martínez Álvarez, Julio César. Instituto Mexicano del Seguro Social; MéxicoFil: López Gil, Concepción. Instituto Mexicano del Seguro Social; MéxicoFil: Adalid Sáinz, Carmen. Instituto Mexicano del Seguro Social; MéxicoFil: Vega Martínez, María del Rosario. Hospital Central Sur de Alta Especialidad; MéxicoFil: Escobedo Ruíz, Araceli. Instituto Mexicano del Seguro Social; MéxicoFil: Juárez Cortés, Eva Dolores. Instituto Mexicano del Seguro Social; MéxicoFil: Immel, Alexander. Max Planck Institute For The Science Of Human History; Alemania. Christian Albrechts Universitat Zu Kiel; AlemaniaFil: Pacheco Ubaldo, Hanna. Instituto Nacional de Antropología E Historia. Escuela Nacional de Antropología E Historia; MéxicoFil: González Medina, Liliana. Instituto Nacional de Antropología E Historia. Escuela Nacional de Antropología E Historia; MéxicoFil: Lona Sánchez, Abraham. Instituto Nacional de Antropología E Historia. Escuela Nacional de Antropología E Historia; MéxicoFil: Lara Riegos, Julio. Universidad Autónoma de Yucatán; MéxicoFil: Sánchez Fernández, María Guadalupe de Jesús. Instituto Mexicano del Seguro Social; MéxicoFil: Díaz López, Rosario. Hospital Central Militar, Mexico City; MéxicoFil: Guizar López, Gregorio Ulises. Hospital Central Militar, Mexico City; MéxicoFil: Medina Escobedo, Carolina Elizabeth. Instituto Mexicano del Seguro Social; MéxicoFil: Arrazola García, María Araceli. Instituto Mexicano del Seguro Social; MéxicoFil: Montiel Hernández, Gustavo Daniel. Instituto Nacional de Antropología E Historia. Escuela Nacional de Antropología E Historia; MéxicoFil: Hernández Hernández, Ofelia. Técnicas Genéticas Aplicadas a la Clínica ; MéxicoFil: Ramos de la Cruz, Flor del Rocío. Instituto Mexicano del Seguro Social; MéxicoFil: Juárez Nicolás, Francisco. Instituto Nacional de Pediatría; MéxicoFil: Pantoja Torres, Jorge Arturo. Instituto Mexicano del Seguro Social; MéxicoFil: Rodríguez Munguía, Tirzo Jesús. Hospital General Norberto Treviño Zapata; MéxicoFil: Juárez Barreto, Vicencio. Hospital Infantil de Mexico Federico Gomez; MéxicoFil: Gonzalez-Jose, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; Argentin

Implementación de RFID en un almacén logístico

Para el desarrollo del presente proyecto se evaluarán las diferentes variables que se necesitan para el funcionamiento de un almacén que alberga tres tipos de productos, para posteriormente evaluar la implementación de la tecnología RFID (en inglés Radio Frecuency Identification) o identificación por radiofrecuencia. El proyecto se divide en tres puntos que se han desarrollado en el proyecto, el primero, definición de los procesos productivos del mismo, el segundo, investigación de la tecnología RFID para fines logísticos y finalmente, la descripción del dimensionamiento del sistema RFID en el almacén logístico de cajas para su evaluación económica. Se evaluaron las condiciones de las instalaciones para que el sistema implementado sea funcional, desde su distribución, tanto de entradas como salidas, pasillos, estanterías, área de recepción, picking y expedición. El almacén para el que se realizó la evaluación del proyecto fue diseñado en función a la información de un almacén logístico de una cadena comercial de Barcelona

Communications coopératives dans les réseaux autour du corps humain pour la capture du mouvement

Wireless Body Area Networks (WBAN) refers to the family of “wearable” wireless sensor networks (WSN) used to collect personal data, such as human activity, heart rate, sleep sequences or geographical position. This thesis aims at proposing cooperative algorithms and cross-layer mechanisms with WBAN to perform large-scale individual motion capture and coordinated group navigation applications. For this purpose, we exploit the advantages of jointly cooperative and heterogeneous WBAN under full/half-mesh topologies for localization purposes, from on-body links at the body scale, body-to-body links between mobile users of a group and off-body links with respect to the environment and the infrastructure. The wireless transmission relies on an impulse radio Ultra-Wideband (IR-UWB) radio (based on the IEEE 802.15.6 standard), in order to obtain accurate peer-to-peer ranging measurements based on Time of Arrival (ToA) estimates. Thus, we address the problem of positioning and ranging estimation through the design of cross-layer strategies by considering realistic body mobility and channel variations. Our first contribution consists in the creation of an unprecedented WBAN measurement database obtained with real experimental scenarios for mobility and channel modelling. Then, we introduce a discrete-event (WSNet) and deterministic (PyLayers) co-simulator tool able to exploit our measurement database to help us on the design and validation of cooperative algorithms. Using these tools, we investigate the impact of nodes mobility and channel variations on the ranging estimation. In particular, we study the “three-way ranging” (3-WR) protocol and we observed that the delays of 3-WR packets have an impact on the distances estimated in function of the speed of nodes. Then, we quantify and compare the error with statistical models and we show that the error generated by the channel is bigger than the mobility error. In a second time, we extend our study for the position estimation. Thus, we analyze different strategies at MAC layer through scheduling and slot allocation algorithms to reduce the impact of mobility. Then, we propose to optimize our positioning algorithm with an extended Kalman filter (EKF), by using our scheduling strategies and the statistical models of mobility and channel errors. Finally, we propose a distributed-cooperative algorithm based on the analysis of long-term and short-term link quality estimators (LQEs) to improve the reliability of positioning. To do so, we evaluate the positioning success rate under three different channel models (empirical, simulated and experimental) along with a conditional algorithm (based on game theory) for virtual anchor choice. We show that our algorithm improve the number of positions estimated for the nodes with the worst localization performance.Les réseaux corporels (WBAN) se réfère aux réseaux de capteurs (WSN) "portables" utilisés pour collecter des données personnelles, telles que la fréquence cardiaque ou l'activité humaine. Cette thèse a pour objectif de proposer des algorithmes coopératifs (PHY/MAC) pour effectuer des applications de localisation, tels que la capture de mouvement et la navigation de groupe. Pour cela, nous exploitons les avantages du WBAN avec différentes topologies et différents types de liens: on-body à l'échelle du corps, body-to-body entre les utilisateurs et off-body par rapport à l'infrastructure. La transmission repose sur une radio impulsionnelle (IR-UWB), afin d'obtenir des mesures de distance précises, basées sur l’estimation du temps d'arrivée (TOA). Ainsi, on s’intéresse au problème du positionnement à travers de la conception de stratégies coopératives et en considérant la mobilité du corps et les variations canal. Notre première contribution consiste en la création d'une base de données obtenue avec de scénarios réalistes pour la modélisation de la mobilité et du canal. Ensuite, nous introduisons un simulateur capable d'exploiter nos mesures pour la conception de protocoles. Grâce à ces outils, nous étudions d’abord l'impact de la mobilité et des variations de canal sur l'estimation de la distance avec le protocole "three way-ranging" (3-WR). Ainsi, nous quantifions et comparons l'erreur avec des modèles statistiques. Dans un second temps, nous analysons différentes algorithmes de gestion de ressources pour réduire l'impact de la mobilité sur l'estimation de position. Ensuite, nous proposons une optimisation avec un filtre de Kalman étendu (EKF) pour réduire l'erreur. Enfin, nous proposons un algorithme coopératif basé sur l'analyse d’estimateurs de qualité de lien (LQEs) pour améliorer la fiabilité. Pour cela, nous évaluons le taux de succès de positionnement en utilisant trois modèles de canaux (empirique, simulé et expérimental) avec un algorithme (basé sur la théorie des jeux) pour le choix des ancres virtuelles

Cooperatif communications with wireless body area networks for motion capture

Les réseaux corporels (WBAN) se réfère aux réseaux de capteurs (WSN) "portables" utilisés pour collecter des données personnelles, telles que la fréquence cardiaque ou l'activité humaine. Cette thèse a pour objectif de proposer des algorithmes coopératifs (PHY/MAC) pour effectuer des applications de localisation, tels que la capture de mouvement et la navigation de groupe. Pour cela, nous exploitons les avantages du WBAN avec différentes topologies et différents types de liens: on-body à l'échelle du corps, body-to-body entre les utilisateurs et off-body par rapport à l'infrastructure. La transmission repose sur une radio impulsionnelle (IR-UWB), afin d'obtenir des mesures de distance précises, basées sur l’estimation du temps d'arrivée (TOA). Ainsi, on s’intéresse au problème du positionnement à travers de la conception de stratégies coopératives et en considérant la mobilité du corps et les variations canal. Notre première contribution consiste en la création d'une base de données obtenue avec de scénarios réalistes pour la modélisation de la mobilité et du canal. Ensuite, nous introduisons un simulateur capable d'exploiter nos mesures pour la conception de protocoles. Grâce à ces outils, nous étudions d’abord l'impact de la mobilité et des variations de canal sur l'estimation de la distance avec le protocole "three way-ranging" (3-WR). Ainsi, nous quantifions et comparons l'erreur avec des modèles statistiques. Dans un second temps, nous analysons différentes algorithmes de gestion de ressources pour réduire l'impact de la mobilité sur l'estimation de position. Ensuite, nous proposons une optimisation avec un filtre de Kalman étendu (EKF) pour réduire l'erreur. Enfin, nous proposons un algorithme coopératif basé sur l'analyse d’estimateurs de qualité de lien (LQEs) pour améliorer la fiabilité. Pour cela, nous évaluons le taux de succès de positionnement en utilisant trois modèles de canaux (empirique, simulé et expérimental) avec un algorithme (basé sur la théorie des jeux) pour le choix des ancres virtuelles.Wireless Body Area Networks (WBAN) refers to the family of “wearable” wireless sensor networks (WSN) used to collect personal data, such as human activity, heart rate, sleep sequences or geographical position. This thesis aims at proposing cooperative algorithms and cross-layer mechanisms with WBAN to perform large-scale individual motion capture and coordinated group navigation applications. For this purpose, we exploit the advantages of jointly cooperative and heterogeneous WBAN under full/half-mesh topologies for localization purposes, from on-body links at the body scale, body-to-body links between mobile users of a group and off-body links with respect to the environment and the infrastructure. The wireless transmission relies on an impulse radio Ultra-Wideband (IR-UWB) radio (based on the IEEE 802.15.6 standard), in order to obtain accurate peer-to-peer ranging measurements based on Time of Arrival (ToA) estimates. Thus, we address the problem of positioning and ranging estimation through the design of cross-layer strategies by considering realistic body mobility and channel variations. Our first contribution consists in the creation of an unprecedented WBAN measurement database obtained with real experimental scenarios for mobility and channel modelling. Then, we introduce a discrete-event (WSNet) and deterministic (PyLayers) co-simulator tool able to exploit our measurement database to help us on the design and validation of cooperative algorithms. Using these tools, we investigate the impact of nodes mobility and channel variations on the ranging estimation. In particular, we study the “three-way ranging” (3-WR) protocol and we observed that the delays of 3-WR packets have an impact on the distances estimated in function of the speed of nodes. Then, we quantify and compare the error with statistical models and we show that the error generated by the channel is bigger than the mobility error. In a second time, we extend our study for the position estimation. Thus, we analyze different strategies at MAC layer through scheduling and slot allocation algorithms to reduce the impact of mobility. Then, we propose to optimize our positioning algorithm with an extended Kalman filter (EKF), by using our scheduling strategies and the statistical models of mobility and channel errors. Finally, we propose a distributed-cooperative algorithm based on the analysis of long-term and short-term link quality estimators (LQEs) to improve the reliability of positioning. To do so, we evaluate the positioning success rate under three different channel models (empirical, simulated and experimental) along with a conditional algorithm (based on game theory) for virtual anchor choice. We show that our algorithm improve the number of positions estimated for the nodes with the worst localization performance