A Study of Medium Access Control Protocols for Wireless Body Area Networks

The seamless integration of low-power, miniaturised, invasive/non-invasive lightweight sensor nodes have contributed to the development of a proactive and unobtrusive Wireless Body Area Network (WBAN). A WBAN provides long-term health monitoring of a patient without any constraint on his/her normal dailylife activities. This monitoring requires low-power operation of invasive/non-invasive sensor nodes. In other words, a power-efficient Medium Access Control (MAC) protocol is required to satisfy the stringent WBAN requirements including low-power consumption. In this paper, we first outline the WBAN requirements that are important for the design of a low-power MAC protocol. Then we study low-power MAC protocols proposed/investigated for WBAN with emphasis on their strengths and weaknesses. We also review different power-efficient mechanisms for WBAN. In addition, useful suggestions are given to help the MAC designers to develop a low-power MAC protocol that will satisfy the stringent WBAN requirements.Comment: 13 pages, 8 figures, 7 table

QoS in Body Area Networks: A survey

Body Area Networks (BANs) are becoming increasingly popular and have shown great potential in real-time monitoring of the human body. With the promise of being cost-effective and unobtrusive and facilitating continuous monitoring, BANs have attracted a wide range of monitoring applications, including medical and healthcare, sports, and rehabilitation systems. Most of these applications are real time and life critical and require a strict guarantee of Quality of Service (QoS) in terms of timeliness, reliability, and so on. Recently, there has been a number of proposals describing diverse approaches or frameworks to achieve QoS in BANs (i.e., for different layers or tiers and different protocols). This survey put these individual efforts into perspective and presents a more holistic view of the area. In this regard, this article identifies a set of QoS requirements for BAN applications and shows how these requirements are linked in a three-tier BAN system and presents a comprehensive review of the existing proposals against those requirements. In addition, open research issues, challenges, and future research directions in achieving these QoS in BANs are highlighted.</jats:p

Nano-Communication for Biomedical Applications: A Review on the State-of-the-Art From Physical Layers to Novel Networking Concepts

We review EM modeling of the human body, which is essential for in vivo wireless communication channel characterization; discuss EM wave propagation through human tissues; present the choice of operational frequencies based on current standards and examine their effects on communication system performance; discuss the challenges of in vivo antenna design, as the antenna is generally considered to be an integral part of the in vivo channel; review the propagation models for the in vivo wireless communication channel and discuss the main differences relative to the ex vivo channel; and address several open research problems and future research directions

A comprehensive survey on hybrid communication in context of molecular communication and terahertz communication for body-centric nanonetworks

With the huge advancement of nanotechnology over the past years, the devices are shrinking into micro-scale, even nano-scale. Additionally, the Internet of nano-things (IoNTs) are generally regarded as the ultimate formation of the current sensor networks and the development of nanonetworks would be of great help to its fulfilment, which would be ubiquitous with numerous applications in all domains of life. However, the communication between the devices in such nanonetworks is still an open problem. Body-centric nanonetworks are believed to play an essential role in the practical application of IoNTs. BCNNs are also considered as domain specific like wireless sensor networks and always deployed on purpose to support a particular application. In these networks, electromagnetic and molecular communications are widely considered as two main promising paradigms and both follow their own development process. In this survey, the recent developments of these two paradigms are first illustrated in the aspects of applications, network structures, modulation techniques, coding techniques and security to then investigate the potential of hybrid communication paradigms. Meanwhile, the enabling technologies have been presented to apprehend the state-of-art with the discussion on the possibility of the hybrid technologies. Additionally, the inter-connectivity of electromagnetic and molecular body-centric nanonetworks is discussed. Afterwards, the related security issues of the proposed networks are discussed. Finally, the challenges and open research directions are presented

Reliable, Context-Aware and Energy-Efficient Architecture for Wireless Body Area Networks in Sports Applications

RÉSUMÉ Un Réseau Corporel Sans Fil (RCSF, Wireless Body Area Network en anglais ou WBAN) permet de collecter de l'information à partir de capteurs corporels. Cette information est envoyée à un hub qui la transforme et qui peut aussi effectuer d'autres fonctions comme gérer des événements corporels, fusionner les données à partir des capteurs, percevoir d’autres paramètres, exécuter les fonctions d’une interface d’utilisateur, et faire un lien vers des infrastructures de plus haut niveau et d’autres parties prenantes. La réduction de la consommation d'énergie d’un RCSF est un des aspects les plus importants qui doit être amélioré lors de sa conception. Cet aspect peut impliquer le développement de protocoles de Contrôles d'Accès au Support (CAS, Media Access Control en anglais ou MAC), protocoles de transport et de routage plus efficients. Le contrôle de la congestion est un autre des facteurs les plus importants dans la conception d’un RCSF, parce que la congestion influe directement sur la Qualité De Service (QDS, Quality of Service en anglais ou QoS) et l’efficience en énergie du réseau. La congestion dans un RCSF peut produire une grande perte de paquets et une haute consommation d’énergie. La QDS est directement impactée par la perte de paquets. L’implémentation de mesures additionnelles est nécessaire pour atténuer l’impact sur la communication des RCSF. Les protocoles de CAS pour RCSF devraient permettre aux capteurs corporels d’accéder rapidement au canal de communication et d’envoyer les données au hub, surtout pour les événements urgents tout en réduisant la consommation d’énergie. Les protocoles de transport pour RCSF doivent fournir de la fiabilité bout-à-bout et de la QDS pour tout le réseau. Cette tâche peut être accomplie par la réduction du ratio de perte de paquets (Packet Loss Ratio en anglais ou PLR) et de la latence tout en gardant l'équité et la faible consommation d'énergie entre les noeuds. Le standard IEEE 802.15.6 suggère un protocole de CAS qui est destiné à être applicable à tous les types de RCSF; toutefois, ce protocole peut être amélioré pour les RCSF utilisés dans le domaine du sport, où la gestion du trafic pourrait être différente d’autres réseaux. Le standard IEEE 802.15.6 comprend la QDS, mais cela ne suggère aucun protocole de transport ou système de contrôle du débit. Le but principal de ce projet de recherche est de concevoir une architecture pour RCSF en trois phases : (i) Conception d’un mécanisme sensible au contexte et efficient en énergie pour fournir une QDS aux RCSF; (ii) Conception d’un mécanisme fiable et efficient en énergie pour fournir une récupération des paquets perdus et de l’équité dans les RCSF; et (iii) Conception d’un système de contrôle du débit sensible au contexte pour fournir un contrôle de congestion aux RCSF. Finalement, ce projet de recherche propose une architecture fiable, sensible au contexte et efficiente en énergie pour RCSF utilisés dans le domaine du sport. Cette architecture fait face à quatre défis : l'efficacité de l'énergie, la sensibilité au contexte, la qualité de service et la fiabilité. La mise en place de cette solution aidera à l’amélioration des compétences, de la performance, de l’endurance et des protocoles d’entraînement des athlètes, ainsi qu’à la détection des points faibles. Cette solution pourrait être prolongée à l’amélioration de la qualité de vie des enfants, des personnes malades ou âgées, ou encore aux domaines militaires, de la sécurité et du divertissement. L’évaluation des protocoles et schémas proposés a été faite par simulations programmées avec le simulateur OMNeT++ et le système Castalia. Premièrement, le protocole de CAS proposé a été comparé avec les protocoles de CAS suivants : IEEE 802.15.6, IEEE 802.15.4 et T-MAC (Timeout MAC). Deuxièmement, le protocole de CAS proposé a été comparé avec le standard IEEE 802.15.6 avec et sans l’utilisation du protocole de transport proposé. Finalement, le protocole de CAS proposé et le standard IEEE 802.15.6 ont été comparés avec et sans l’utilisation du système de contrôle du débit proposé. Le protocole de CAS proposé surpasse les protocoles de CAS IEEE 802.15.6, IEEE 802.15.4 et T-MAC dans le pourcentage de pertes de paquets d’urgence et normaux, l’efficacité en énergie, et la latence du trafic d’urgence et du trafic normal. Le protocole de CAS proposé utilisé avec le protocole du transport proposé surpasse la performance du standard IEEE 802.15.6 dans le pourcentage de perte de paquets avec ou sans trafic d’urgence, l’efficacité en énergie, et la latence du trafic normal. Le système de contrôle du débit proposé a amélioré la performance du protocole de CAS proposé et du standard IEEE 802.15.6 dans le pourcentage de perte de paquets avec ou sans trafic d’urgence, l’efficacité en énergie, et la latence du trafic d’urgence.----------ABSTRACT Information collected from body sensors in a Wireless Body Area Network (WBAN) is sent to a hub or coordinator which processes the information and can also perform other functions such as managing body events, merging data from sensors, sensing other parameters, performing the functions of a user interface and bridging the WBAN to higher-level infrastructure and other stakeholders. The reduction of the power consumption of a WBAN is one of the most important aspects to be improved when designing a WBAN. This challenge might imply the development of more efficient Medium Access Control (MAC), transport and routing protocols. Congestion control is another of the most important factors when a WBAN is designed, due to its direct impact in the Quality of Service (QoS) and the energy efficiency of the network. The presence of congestion in a WBAN can produce a big packet loss and high energy consumption. The QoS is also impacted directly by the packet loss. The implementation of additional measures is necessary to mitigate the impact on WBAN communications. The MAC protocols for WBANs should allow body sensors to get quick access to the channel and send data to the hub, especially in emergency events while reducing the power consumption. The transport protocols for WBANs must provide end-to-end reliability and QoS for the whole network. This task can be accomplished through the reduction of both the Packet Loss Ratio (PLR) and the latency while keeping fairness and low power consumption between nodes. The IEEE 802.15.6 standard suggests a MAC protocol which is intended to be applicable for all kinds of WBANs. Nonetheless, it could be improved for sports WBANs where the traffic-types handling could be different from other networks. The IEEE 802.15.6 standard supports QoS, but it does not suggest any transport protocol or rate control scheme. The main objective of this research project is to design an architecture for WBANs in three phases: (i) Designing a context-aware and energy-efficient mechanism for providing QoS in WBANs; (ii) Designing a reliable and energy-efficient mechanism to provide packet loss recovery and fairness in WBANs; and (iii) Designing a context-aware rate control scheme to provide congestion control in WBANs. Finally, this research project proposes a reliable, context-aware and energy-efficient architecture for WBANs used in sports applications, facing four challenges: energy efficiency, context awareness, quality of service and reliability. The benefits of this solution will help to improve skills, performance, endurance and training protocols of athletes, and deficiency detection. Also, it could be extended to enhance the quality of life of children, ill and elderly people, and to security, military and entertainment fields. The evaluation of the proposed protocols and schemes was made through simulations programed in the OMNeT++ simulator and the Castalia framework. First, the proposed MAC protocol was compared against the IEEE 802.15.6 MAC protocol, the IEEE 802.15.4 MAC protocol and the T-MAC (Timeout MAC) protocol. Second, the proposed MAC protocol was compared with the IEEE 802.15.6 standard with and without the use of the proposed transport protocol. Finally, both the proposed MAC protocol and the IEEE 802.15.6 standard were compared with and without the use of the proposed rate control scheme. The proposed MAC protocol outperforms the IEEE 802.15.6 MAC protocol, the IEEE 802.15.4 MAC protocol and the T-MAC protocol in the percentage of emergency and normal packet loss, the energy effectiveness, and the latency of emergency and normal traffic. The proposed MAC protocol working along with the proposed transport protocol outperforms the IEEE 802.15.6 standard in the percentage of the packet loss with or without emergency traffic, the energy effectiveness, and the latency of normal traffic. The proposed rate control scheme improved the performance of both the proposed MAC protocol and the IEEE 802.15.6 standard in the percentage of the packet loss with or without emergency traffic, the energy effectiveness and the latency of emergency traffic

Ultra-Low Power Wirel ess Sensor Networks: Overview of Applications , Design Requirements and Challenges

Wireless Sensor Networks (WSNs) have received significant attention from various researchers in terms of its architecture, design, challenges and supporting technologies, and so on. Also, their applications to different aspect such as structural health monitoring, health care, precision agriculture, intelligent transport systems have been reported. Though, some authors have reviewed different aspects of wireless sensor nodes, including applications, this paper presents a short survey of selected literature from a pool of articles reporting application cases of ultra-low power WSNs published in 2010- 2017. In this paper, specific design requirements for using ultra-low power sensor nodes were highlighted. In addition, existing solutions to challenges encountered when using WSNs for the selected applications were examined. This short survey will help readers and practitioners with scholarly resource needed for understanding the state-of-the-art in ultra-low power wireless sensor applications and offers insight into areas for further research. It will also help researchers to become aware of potential collaborators in future works involving WSNs

Abstracting information on body area networks

Healthcare is changing, correction...healthcare is in need of change. The population ageing, the increase in chronic and heart diseases and just the increase in population size will overwhelm the current hospital-centric healthcare. There is a growing interest by individuals to monitor their own physiology. Not only for sport activities, but also to control their own diseases. They are changing from the passive healthcare receiver to a proactive self-healthcare taker. The focus is shifting from hospital centred treatment to a patient-centric healthcare monitoring. Continuous, everyday, wearable monitoring and actuating is part of this change. In this setting, sensors that monitor the heart, blood pressure, movement, brain activity, dopamine levels, and actuators that pump insulin, “pump” the heart, deliver drugs to specific organs, stimulate the brain are needed as pervasive components in and on the body. They will tend for people’s need of self-monitoring and facilitate healthcare delivery. These components around a human body that communicate to sense and act in a coordinated fashion make a Body Area Network (BAN). In most cases, and in our view, a central, more powerful component will act as the coordinator of this network. These networks aim to augment the power to monitor the human body and react to problems discovered with this observation. One key advantage of this system is their overarching view of the whole network. That is, the central component can have an understanding of all the monitored signals and correlate them to better evaluate and react to problems. This is the focus of our thesis. In this document we argue that this multi-parameter correlation of the heterogeneous sensed information is not being handled in BANs. The current view depends exclusively on the applica- tion that is using the network and its understanding of the parameters. This means that every application will oversee the BAN’s heterogeneous resources managing them directly without taking into consideration other applications, their needs and knowledge. There are several physiological correlations already known by the medical field. Correlating blood pressure and cross sectional area of blood vessels to calculate blood velocity, estimating oxygen delivery from cardiac output and oxygen saturation, are such examples. This knowledge should be available in a BAN and shared by the several applications that make use of the network. This architecture implies a central component that manages the knowledge and the resources. And this is, in our view, missing in BANs. Our proposal is a middleware layer that abstracts the underlying BAN’s resources to the applica- tion, providing instead an information model to be queried. The model describes the correlations for producing new information that the middleware knows about. Naturally, the raw sensed data is also part of the model. The middleware hides the specificities of the nodes that constitute the BAN, by making available their sensed production. Applications are able to query for information attaching requirements to these requests. The middleware is then responsible for satisfying the requests while optimising the resource usage of the BAN. Our architecture proposal is divided in two corresponding layers, one that abstracts the nodes’ hardware (hiding node’s particularities) and the information layer that describes information available and how it is correlated. A prototype implementation of the architecture was done to illustrate the concept.This work was partially supported by PhD scholarship SFRH/BD/28843/2006 from Fundação da Ciência e Tecnologia from Portugal

24 GHz Wearable Antenna Design for Wireless Body Area Networks: An Investigation of On-Body Channel Characterisation and Zigbee Protocol at 24 GHz

User-centric networks drive the evolution of wireless communication, demanding constant connectivity and services across various domains. MM-wave (24 GHz ISM band) frequencies emerge as a promising solution for WBAN, overcoming challenges posed by the on-body radio channel and achieving reliable communication in diverse environments. This thesis uses multiple antennas to characterise the mm-wave (24 GHz) radio propagation channel for body-centric communication. The aim is to design compact antennas insensitive to human skin and structural deformation, exploring system-level modelling of Zigbee's PHY and MAC layers in the context of mm-wave (24 GHz) Body Area Networks (BWAN). The first part introduces innovative on-body antenna designs, incorporating split square-ring electromagnetic bandgap (EBG) structures and bow-tie slot antennas, demonstrating high insensitivity to body proximity and bending. The study also proposes Koch fractal antennas backed by EBG structures for improved performance and stable radiation patterns suitable for on-skin mounting. The second part analyses 24 GHz on-body communication system performance and path loss modelling, considering various antenna types. Measurement campaigns confirm the significance of antenna diversity and position in mm-wave propagation on the human body, predicting potential performance for 24 GHz ISM band WBAN systems. The third part evaluates Zigbee protocol performance in body-centric wireless communication within the 24 GHz channel model. Results show good radio link quality for physiological sensor nodes, with lower performance observed in NLOS and PLOS scenarios due to body tissue obstruction. Throughput performance highlights the importance of sensor positioning and MAC layer optimisation. This thesis advances 24 GHz ISM band WBANs through innovative antennas, introducing 24 GHz path loss modeling, and insights into Zigbee (physical layer and MAC) protocol. It drives future research in advanced designs, propagation modelling, and protocol enhancements, boosting on-body wireless communication capabilities