612 research outputs found
Mathematical modeling of ultra wideband in vivo radio channel
This paper proposes a novel mathematical model for an in vivo radio channel at ultra-wideband frequencies (3.1â10.6 GHz), which can be used as a reference model for in vivo channel response without performing intensive experiments or simulations. The statistics of error prediction between experimental and proposed model is RMSE = 5.29, which show the high accuracy of the proposed model. Also, the proposed model was applied to the blind data, and the statistics of error prediction is RMSE = 7.76, which also shows a reasonable accuracy of the model. This model will save the time and cost on simulations and experiments, and will help in designing an accurate link budget calculation for a future enhanced system for ultra-wideband body-centric wireless systems
A comprehensive survey of wireless body area networks on PHY, MAC, and network layers solutions
Recent advances in microelectronics and integrated circuits, system-on-chip design, wireless communication and intelligent low-power sensors have allowed the realization of a Wireless Body Area Network (WBAN). A WBAN is a collection of low-power, miniaturized, invasive/non-invasive lightweight wireless sensor nodes that monitor the human body functions and the surrounding environment. In addition, it supports a number of innovative and interesting applications such as ubiquitous healthcare, entertainment, interactive gaming, and military applications. In this paper, the fundamental mechanisms of WBAN including architecture and topology, wireless implant communication, low-power Medium Access Control (MAC) and routing protocols are reviewed. A comprehensive study of the proposed technologies for WBAN at Physical (PHY), MAC, and Network layers is presented and many useful solutions are discussed for each layer. Finally, numerous WBAN applications are highlighted
A Twin Spiral Planar Antenna for UWB Medical Radars
A planar-spiral antenna to be used in an ultrawideband (UWB) radar system for heart activity monitoring is presented. The antenna, named âtwin,â is constituted by two spiral dipoles in a compact structure. The reflection coefficient at the feed point of the dipoles is lower than â8âdB over the 3â12âGHz band, while the two-dipoles coupling is about â20âdB. The radiated beam is perpendicular to the plane of the spiral, so the antenna is wearable and it may be an optimal radiator for a medical UWB radar for heart rate detection. The designed antenna has been also used to check some hypotheses about the UWB radar heart activity detection mechanism. The radiation impedance variation, caused by the thorax vibrations associated with heart activity, seems to be the most likely explanation of the UWB radar operation
Modelling and characterisation of antennas and propagation for body-centric wireless communication
PhDBody-Centric Wireless Communication (BCWC) is a central point in the development
of fourth generation mobile communications. The continuous miniaturisation of sensors,
in addition to the advancement in wearable electronics, embedded software, digital
signal processing and biomedical technologies, have led to a new concept of usercentric
networks, where devices can be carried in the userâs pockets, attached to the
userâs body or even implanted.
Body-centric wireless networks take their place within the personal area networks,
body area networks and body sensor networks which are all emerging technologies
that have a broad range of applications such as healthcare and personal entertainment.
The major difference between BCWC and conventional wireless systems is the
radio channel over which the communication takes place. The human body is a hostile
environment from radio propagation perspective and it is therefore important to understand
and characterise the effect of the human body on the antenna elements, the
radio channel parameters and hence the system performance. This is presented and
highlighted in the thesis through a combination of experimental and electromagnetic
numerical investigations, with a particular emphasis to the numerical analysis based
on the finite-difference time-domain technique.
The presented research work encapsulates the characteristics of the narrowband
(2.4 GHz) and ultra wide-band (3-10 GHz) on-body radio channels with respect to
different digital phantoms, body postures, and antenna types hence highlighting the
effect of subject-specific modelling, static and dynamic environments and antenna performance
on the overall body-centric network. The investigations covered extend further
to include in-body communications where the radio channel for telemetry with
medical implants is also analysed by considering the effect of different digital phantoms
on the radio channel characteristics. The study supports the significance of developing
powerful and reliable numerical modelling to be used in conjunction with measurement campaigns for a comprehensive understanding of the radio channel in
body-centric wireless communication. It also emphasises the importance of considering
subject-specific electromagnetic modelling to provide a reliable prediction of the
network performance
Ultrawideband Technology for Medical In-Body Sensor Networks: An Overview of the Human Body as a Propagation Medium, Phantoms, and Approaches for Propagation Analysis
[EN] An in-body sensor network is that in which at least one of the sensors is located inside the human body. Such wireless in-body sensors are used mainly in medical applications, collecting and monitoring important parameters for health and disease treatment. IEEE Standard 802.15.6-2012 for wireless body area networks (WBANs) considers in-body communications in the Medical Implant Communications Service (MICS) band. Nevertheless, high-data-rate communications are not feasible at the MICS band because of its narrow occupied bandwidth. In this framework, ultrawideband (UWB) systems have emerged as a potential solution for in-body highdata-rate communications because of their miniaturization capabilities and low power consumption.This work was supported by the Programa de Ayudas de InvestigaciĂłn y Desarrollo (PAID-01-16) at the Universitat PolitĂšcnica de ValĂšncia, Spain; by the Ministerio de EconomĂa y Competitividad, Spain (TEC2014-60258-C2-1-R); and by the European FEDER funds. It was also funded by the European Unionâs H2020:MSCA:ITN program for the Wireless In-Body Environ-ment CommunicationâWiBEC project under grant 675353.Garcia-Pardo, C.; Andreu-EstellĂ©s, C.; FornĂ©s Leal, A.; CastellĂł-Palacios, S.; PĂ©rez-Simbor, S.; Barbi, M.; VallĂ©s Lluch, A.... (2018). Ultrawideband Technology for Medical In-Body Sensor Networks: An Overview of the Human Body as a Propagation Medium, Phantoms, and Approaches for Propagation Analysis. IEEE Antennas and Propagation Magazine. 60(3):19-33. https://doi.org/10.1109/MAP.2018.2818458S193360
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
Feasibility Study and Design of a Wearable System-on-a-Chip Pulse Radar for Contactless Cardiopulmonary Monitoring
A new system-on-a-chip radar sensor for next-generation wearable wireless interface applied to the human health care and safeguard is presented. The system overview is provided and the feasibility study of the radar sensor is presented. In detail, the overall system consists of a radar sensor for detecting the heart and breath rates and a low-power IEEE 802.15.4 ZigBee radio interface, which provides a wireless data link with remote data acquisition and control units. In particular, the pulse radar exploits 3.1â10.6 GHz ultra-wideband signals which allow a significant reduction of the transceiver complexity and then of its power consumption. The operating principle of the radar for the cardiopulmonary monitoring is highlighted and the results of the system analysis are reported. Moreover, the results obtained from the building-blocks design, the channel measurement, and the ultra-wideband antenna realization are reported
Detecting Vital Signs with Wearable Wireless Sensors
The emergence of wireless technologies and advancements in on-body sensor design can enable change in the conventional health-care system, replacing it with wearable health-care systems, centred on the individual. Wearable monitoring systems can provide continuous physiological data, as well as better information regarding the general health of individuals. Thus, such vital-sign monitoring systems will reduce health-care costs by disease prevention and enhance the quality of life with disease management. In this paper, recent progress in non-invasive monitoring technologies for chronic disease management is reviewed. In particular, devices and techniques for monitoring blood pressure, blood glucose levels, cardiac activity and respiratory activity are discussed; in addition, on-body propagation issues for multiple sensors are presented
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