82 research outputs found
Developing a neighborhood-scale wireless notification prototype
We outline an innovative approach to thedevelopment of a prototype of a neighborhoodnotification system (NNS). The NNS applicationresiding on smart phones will use software definedradio and cognitive radio components to interfacewith radio frequency transceivers. Mesh networkingis proposed for emergency notification and disasterresponse coordination using NNS. Our focus hasbeen on the IEEE 802.15.4 and the very recent IEEE802.15.5 mesh networking standard for low data rateconnectivity among low power nodes (or nodeswhose power consumption needs to be low). Theinnovation stems from bringing together differenthardware and software components â some of which,like our Software Defined Radio (SDR) platform, arethemselves still evolving and others, like themeshing platform, are very new â to propose anadaptive, reconfigurable, infrastructure-less ad hocwireless solution to emergency communications inthe unlicensed ISM RF band
Wireless networks for traffic light control on urban and aerotropolis roads
This paper presents a traffic lights system based on wireless communication, providing a support infrastructure for intelligent control in smart cities and aerotropolis scope. An aerotropolis is a metropolitan subregion which infrastructure is centered around an airport [1]. Traffic intensity is increasing all over the world. Intelligent dynamic traffic lights system control are sought for replacing classic conventional manual and time based systems. In this work a wireless sensors network is designed and implemented to feed real time data to the intelligent traffic lights systems control. A physical prototype is implemented for experimental validation outside laboratory environment. The physical prototype shows robustness against unexpected issues or local failures. Results are positive in the scope of the experiences made and promising in terms of extending the tests to larger areas
A survey on mobility management protocols in Wireless Sensor Networks based on 6LoWPAN technology
International audienceMobility has the advantage of enlarging WSN applications. However, proposing a mobility support protocol in Wireless Sensor Networks (WSNs) represents a significant challenge. In this paper, we propose a survey on the mobility management protocols in Wireless Sensor Networks based on 6LoWPAN technology. This technology enables to connect IP sensor devices to other IP networks without any need for gateways. We highlight the advantages and drawbacks with performances issues of each studied solution. Then, in order to select a typical classification of mobility management protocols in WSNs, we provide some classification criteria and approaches on which these protocols are based. Finally, we present a comparative study of the existing protocols in terms of the required performances for this network type
Wireless body sensor networks for health-monitoring applications
This is an author-created, un-copyedited version of an article accepted for publication in
Physiological Measurement. The publisher is
not responsible for any errors or omissions in this version of the manuscript or any version
derived from it. The Version of Record is available online at http://dx.doi.org/10.1088/0967-3334/29/11/R01
Wireless sensor network for health monitoring
Wireless Sensor Network (WSN) is becoming a significant enabling technology for a wide variety of applications. Recent advances in WSN have facilitated the realization of pervasive health monitoring for both homecare and hospital environments. Current technological advances in sensors, power-efficient integrated circuits, and wireless communication have allowed the development of miniature, lightweight, low-cost, and smart physiological sensor nodes. These nodes are capable of sensing, processing, and communicating one or more vital signs. Furthermore, they can be used in wireless personal area networks (WPANs) or wireless body sensor networks (WBSNs) for health monitoring. Many studies were performed and/or are under way in order to develop flexible, reliable, secure, real-time, and power-efficient WBSNs suitable for healthcare applications. To efficiently control and monitor a patientâs status as well as to reduce the cost of power and maintenance, IEEE 802.15.4/ZigBee, a communication standard for low-power wireless communication, is developed as a new efficient technology in health monitoring systems. The main contribution of this dissertation is to provide a modeling, analysis, and design framework for WSN health monitoring systems. This dissertation describes the applications of wireless sensor networks in the healthcare area and discusses the related issues and challenges. The main goal of this study is to evaluate the acceptance of the current wireless standard for enabling WSNs for healthcare monitoring in real environment. Its focus is on IEEE 802.15.4/ZigBee protocols combined with hardware and software platforms. Especially, it focuses on Carrier Sense Multiple Access with Collision Avoidance mechanism (CSMA/CA) algorithms for reliable communication in multiple accessing networks. The performance analysis metrics are established through measured data and mathematical analysis.
This dissertation evaluates the network performance of the IEEE 802.15.4 unslotted CSMA/CA mechanism for different parameter settings through analytical modeling and simulation. For this protocol, a Markov chain model is used to derive the analytical expression of normalized packet transmission, reliability, channel access delay, and energy consumption. This model is used to describe the stochastic behavior of random access and deterministic behavior of IEEE 802.15.4 CSMA/CA. By using it, the different aspects of health monitoring can be analyzed. The sound transmission of heart beat with other smaller data packet transmission is studied. The obtained theoretical analysis and simulation results can be used to estimate and design the high performance health monitoring systems
A critical analysis of research potential, challenges and future directives in industrial wireless sensor networks
In recent years, Industrial Wireless Sensor Networks (IWSNs) have emerged as an important research theme with applications spanning a wide range of industries including automation, monitoring, process control, feedback systems and automotive. Wide scope of IWSNs applications ranging from small production units, large oil and gas industries to nuclear fission control, enables a fast-paced research in this field. Though IWSNs offer advantages of low cost, flexibility, scalability, self-healing, easy deployment and reformation, yet they pose certain limitations on available potential and introduce challenges on multiple fronts due to their susceptibility to highly complex and uncertain industrial environments. In this paper a detailed discussion on design objectives, challenges and solutions, for IWSNs, are presented. A careful evaluation of industrial systems, deadlines and possible hazards in industrial atmosphere are discussed. The paper also presents a thorough review of the existing standards and industrial protocols and gives a critical evaluation of potential of these standards and protocols along with a detailed discussion on available hardware platforms, specific industrial energy harvesting techniques and their capabilities. The paper lists main service providers for IWSNs solutions and gives insight of future trends and research gaps in the field of IWSNs
The role of cross-layered designs in wireless body area network
With recent advancement, Wireless Body Area Network (WBAN) plays an important role to detect various diseases of a patient in advance and informs the medical team about the life threatening situation. WBAN comprises of small intelligent Biomedical sensors which are implanted inside patient body and attached on the surface of a patient to monitor different vital signs, namely; respiratory rate, ECG, EMG, temperature, blood pressure, glucose. The routing layer of WBAN has the same challenging problems as similarly faced in WSN but the unique challenge is the temperature-rise during monitoring of vital signs and data transmission. IEEE 802.15.6 MAC Superframe of WBAN is different from IEEE 802.15.4 MAC of WSN and provides channels to emergency and non-emergency data for transmission. As similarly seen in WSN, PHY layer of IEEE 802.15.4 and IEEE 802.15.6 provide various modulation techniques for data transmission. The purpose of this study is to familiar with routing layer, MAC layer and PHY layer in the cross-layer design of WBA
A MAC protocol for quality of service provisioning in adaptive biomedical wireless sensor networks
Doctorate program on Electronics and Computer EngineeringNew healthcare solutions are being explored to improve the quality of care and the
quality of life of patients, as well as the sustainability and efficiency of the healthcare
services. In this context, wireless sensor networks (WSNs) constitute a key technology
for closing the loop between patients and healthcare providers, as WSNs provide
sensing ability, as well as mobility and portability, essential characteristics for wide
acceptance of wireless healthcare technology.
Despite the recent advances in the field, the wide adoption of healthcare WSNs is still
conditioned by quality of service (QoS) issues, namely at the medium access control
(MAC) level. MAC protocols currently available for WSNs are not able to provide the
required QoS to healthcare applications in scenarios of medical emergency or intensive
medical care. To cover this shortage, the present work introduces a MAC protocol with
novel concepts to assure the required QoS regarding the data transmission robustness,
packet delivery deadline, bandwidth efficiency, and energy preservation. The proposed
MAC protocol provides a new and efficient dynamic reconfiguration mechanism, so
that relevant operational parameters may be redefined dynamically in accordance with
the patientsâ clinical state. The protocol also provides a channel switching mechanism
and the capacity of forwarding frames in two-tier network structures.
To test the performance of the proposed MAC protocol and compare it with other
MAC protocols, a simulation platform was implemented. In order to validate the
simulation results, a physical testbed was implemented to replicate the tests and verify
the results. Sensor nodes were specifically designed and assembled to implement this
physical testbed. New healthcare solutions are being explored to improve the quality of care and the
quality of life of patients, as well as the sustainability and efficiency of the healthcare
services. In this context, wireless sensor networks (WSNs) constitute a key technology
for closing the loop between patients and healthcare providers, as WSNs provide
sensing ability, as well as mobility and portability, essential characteristics for wide
acceptance of wireless healthcare technology.
Despite the recent advances in the field, the wide adoption of healthcare WSNs is still
conditioned by quality of service (QoS) issues, namely at the medium access control
(MAC) level. MAC protocols currently available for WSNs are not able to provide the
required QoS to healthcare applications in scenarios of medical emergency or intensive
medical care. To cover this shortage, the present work introduces a MAC protocol with
novel concepts to assure the required QoS regarding the data transmission robustness,
packet delivery deadline, bandwidth efficiency, and energy preservation. The proposed
MAC protocol provides a new and efficient dynamic reconfiguration mechanism, so
that relevant operational parameters may be redefined dynamically in accordance with
the patientsâ clinical state. The protocol also provides a channel switching mechanism
and the capacity of forwarding frames in two-tier network structures.
To test the performance of the proposed MAC protocol and compare it with other
MAC protocols, a simulation platform was implemented. In order to validate the
simulation results, a physical testbed was implemented to replicate the tests and verify
the results. Sensor nodes were specifically designed and assembled to implement this
physical testbed. Preliminary tests using the simulation and physical platforms showed that simulation
results diverge significantly from reality, if the performance of the WSN software
components is not considered. Therefore, a parametric model was developed to reflect
the impact of this aspect on a physical WSN. Simulation tests using the parametric
model revealed that the results match satisfactorily those obtained in reality.
After validating the simulation platform, comparative tests against IEEE 802.15.4, a
prominent standard used in many wireless healthcare systems, showed that the proposed
MAC protocol leads to a performance increase regarding diverse QoS metrics, such as
packet loss and bandwidth efficiency, as well as scalability, adaptability, and power
consumption. In this way, AR-MAC is a valuable contribution to the deployment of
wireless e-health technology and related applications.Novas soluçÔes de cuidados de saĂșde estĂŁo a ser exploradas para melhorar a qualidade
de tratamento e a qualidade de vida dos pacientes, assim como a sustentabilidade e
eficiĂȘncia dos serviços de cuidado de saĂșde. Neste contexto, as redes de sensores sem
fios (wireless sensor networks - WSN) sĂŁo uma tecnologia chave para fecharem o ciclo
entre os pacientes e os prestadores de cuidados de saĂșde, uma vez que as WSNs
proporcionam não só capacidade sensorial mas também mobilidade e portabilidade,
caracteristicas essenciais para a aceitação à larga escala da tecnologia dos cuidados de
saĂșde sem fios.
Apesar dos avanços recentes na årea, a aceitação genérica das WSNs de cuidados de
saĂșde ainda estĂĄ condicionada por aspectos relacionados com a qualidade de serviço
(quality of service - QoS), nomeadamente ao nĂvel do controlo de acesso ao meio
(medium access control - MAC). Os protocolos MAC actualmente disponĂveis para
WSNs são incapazes de fornecer a QoS desejada pelas aplicaçÔes médicas em cenårios
de emergĂȘncia ou cuidados mĂ©dicos intensivos. Para suprimir esta carĂȘncia, o presente
trabalho apresenta um protocolo MAC com novos conceitos a fim de assegurar a QoS
respeitante Ă robustez de transmissĂŁo de dados, ao limite temporal da entrega de
pacotes, à utilização da largura de banda e à preservação da energia eléctrica. O
protocolo MAC proposto dispÔe de um novo e eficiente mecanismo de reconfiguração
para que os parĂąmetros operacionais relevantes possam ser redefinidos dinamicamente
de acordo com o estado de saĂșde do paciente. O protocolo tambĂ©m oferece um
mecanismo autónomo de comutação de canal, bem como a capacidade de encaminhar
pacotes em redes de duas camadas.
Para testar o desempenho do protocolo MAC proposto e comparĂĄ-lo com outros
protocolos MAC foi implementada uma plataforma de simulação. A fim de validar os
resultados da simulação foi tambĂ©m implementada uma plataforma fĂsica para permitir
replicar os testes e verificar os resultados. Esta plataforma fĂsica inclui nĂłs sensoriais
concebidos e construĂdos de raiz para o efeito. Testes preliminares usando as plataformas de simulação e fĂsica mostraram que os
resultados de simulação divergem significativamente da realidade, caso o desempenho
dos componentes do software presentes nos componentes da WSN nĂŁo seja
considerado. Por conseguinte, desenvolveu-se um modelo paramétrico para reflectir o
impacto deste aspecto numa WSN real. Testes de simulação efectuados com o modelo
paramétrico apresentaram resultados muito satisfatórios quando comparados com os
obtidos na realidade.
Uma vez validada a plataforma de simulação, efectuaram-se testes comparativos com
a norma IEEE 802.15.4, proeminentemente usada em projectos académicos de cuidados
de saĂșde sem fios. Os resultados mostraram que o protocolo MAC conduz a um
desempenho superior no tocante a diversas métricas QoS, tais como perdas de pacotes e
utilização de largura de banda, bem como no respeitante à escalabilidade,
adaptabilidade e consumo de energia eléctrica. Assim sendo, o protocolo MAC proposto
representa um valioso contributo para a concretização efectiva dos cuidados de saĂșde
sem fios e suas aplicaçÔes
MAC protocols for low-latency and energy-efficient WSN applications
Most of medium access control (MAC) protocols proposed for wireless sensor
networks (WSN) are targeted only for single main objective, the energy
efficiency. Other critical parameters such as low-latency, adaptivity to
traffic conditions, scalability, system fairness, and bandwidth utilization
are mostly overleaped or dealt as secondary objectives. The demand to address
those issues increases with the growing interest in cheap, low-power, low-
distance, and embedded WSNs. In this report, along with other vital
parameters, we discuss suitability and limitations of different WSN MAC
protocols for time critical and energy-efficient applications. As an example,
we discuss the working of IEEE 802.15.4 in detail, explore its limitations,
and derive efficient application-specific network parameter settings for time,
energy, and bandwidth critical applications. Eventually, a new WSN MAC
protocol Asynchronous Real-time Energy-efficient and Adaptive MAC (AREA-MAC)
is proposed, which is intended to deal efficiently with time critical
applications, and at the same time, to provide a better trade-off between
other vital parameters, such as energy-efficiency, system fairness,
throughput, scalability, and adaptivity to traffic conditions. On the other
hand, two different optimization problems have been formulated using
application-based traffic generating scenario to minimize network latency and
maximize its lifetime
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