Paired Snap-On Buttons Connections for Balanced Antennas in Wearable Systems

Chen, Shengjian Jammy; Fumeaux, Christophe; Ranasinghe, Damith C.; Kaufmann, Thomas

doi:10.1109/lawp.2014.2363852

Cited by 31 publications

(16 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Third, in terms of sensor improvements, further research needs to improve resistance to wear-and-tear and reduce its size and visibility, as was also suggested by the results from the acceptability study, without losing performance. We have already made progress toward that end [ 58 ]. Future research must consider a trial with a larger cohort of hospitalized older people wearing a less obtrusive and more robust sensor prototype for longer periods and include scenarios such as staff interacting with patients and people visiting patients and changing the location of the chair.…”

Section: Discussionmentioning

confidence: 99%

A battery-less and wireless wearable sensor system for identifying bed and chair exits in a pilot trial in hospitalized older people

et al. 2017

View full text Add to dashboard Cite

Falls in hospitals are common, therefore strategies to minimize the impact of these events in older patients and needs to be examined. In this pilot study, we investigate a movement monitoring sensor system for identifying bed and chair exits using a wireless wearable sensor worn by hospitalized older patients. We developed a movement monitoring sensor system that recognizes bed and chair exits. The system consists of a machine learning based activity classifier and a bed and chair exit recognition process based on an activity score function. Twenty-six patients, aged 71 to 93 years old, hospitalized in the Geriatric Evaluation and Management Unit participated in the supervised trials. They wore over their attire a battery-less, lightweight and wireless sensor and performed scripted activities such as getting off the bed and chair. We investigated the system performance in recognizing bed and chair exits in hospital rooms where RFID antennas and readers were in place. The system’s acceptability was measured using two surveys with 0–10 likert scales. The first survey measured the change in user perception of the system before and after a trial; the second survey, conducted only at the end of each trial, measured user acceptance of the system based on a multifactor sensor acceptance model. The performance of the system indicated an overall recall of 81.4%, precision of 66.8% and F-score of 72.4% for joint bed and chair exit recognition. Patients demonstrated improved perception of the system after use with overall score change from 7.8 to 9.0 and high acceptance of the system with score ≥ 6.7 for all acceptance factors. The present pilot study suggests the use of wireless wearable sensors is feasible for detecting bed and chair exits in a hospital environment.

show abstract

Section: Discussionmentioning

confidence: 99%

A battery-less and wireless wearable sensor system for identifying bed and chair exits in a pilot trial in hospitalized older people

et al. 2017

View full text Add to dashboard Cite

show abstract

“…First, the reliability of interconnections between flexible and rigid subsystems needs addressing, for example by using snap-on fasteners, as reported in [13]. Second, in order to maximize the output power, and obtain a range of several meters, rectification and power management circuits need to be efficient down to extremely low power levels [14].…”

Section: Figmentioning

confidence: 99%

“…Specifically, at RF where insertion loss and stability of the interconnection are of most important. In order to avoid the use of fragile coaxial cable connection, metallic snap-on buttons have been proposed with a working frequency range up to 5 GHz and insertion loss better than 0.8 dB [13]. Similarly, conductive hook and loop fastener was proposed in [30] with insertion loss about 1 dB at 4 GHz.…”

Section: Fabric-to-rigid Pcb Interface Designmentioning

confidence: 99%

A Flexible 2.45-GHz Power Harvesting Wristband With Net System Output From −24.3 dBm of RF Power

Adami

Proynov

Hilton

et al. 2018

IEEE Trans. Microwave Theory Techn.

145

159

View full text Add to dashboard Cite

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Abstract-This paper presents a flexible 2.45-GHz wireless power harvesting wristband that generates a net dc output from a −24.3-dBm RF input. This is the lowest reported system sensitivity for systems comprising a rectenna and impedancematching power management. A complete system has been implemented comprising: a fabric antenna, a rectifier on rigid substrate, a contactless electrical connection between rigid and flexible subsystems, and power electronics impedance matching. Various fabric and flexible materials are electrically characterized at 2.45 GHz using the two-line and the T-resonator methods. Selected materials are used to design an all-textile antenna, which demonstrates a radiation efficiency above 62% on a phantom irrespective of location, and a stable radiation pattern. The rectifier, designed on a rigid substrate, shows a best-inclass efficiency of 33.6% at −20 dBm. A reliable, efficient, and wideband contactless connection between the fabric antenna and the rectifier is created using broadside-coupled microstrip lines, with an insertion loss below 1 dB from 1.8 to over 10 GHz. A self-powered boost converter with a quiescent current of 150 nA matches the rectenna output with a matching efficiency above 95%. The maximum end-to-end efficiency is 28.7% at −7 dBm. The wristband harvester demonstrates net positive energy harvesting from −24.3 dBm, a 7.3-dB improvement on the state of the art.

show abstract

“…On the one hand, they are selected as mechanical fixtures since their size are appropriate for the patch modules, and more importantly, they offer solid mechanical performance. A dedicated test done in [23] indicates that an approximate 3 N force is needed to undo engaged buttons of this type. On the other hand, since these snap-on buttons offer detachable connection with satisfactory RF performance at least up to 5 GHz [23], they are also chosen as an RF connector for the PIFA antenna configuration.…”

Section: B Snap-on Buttonsmentioning

confidence: 99%

“…Moreover, clothing closure accessories have been exploited as support for antenna design. For example, metallic buttons for textiles have been designed as wearable antennas [19], [20], and commercial metallic snap-on buttons also have been proposed as a practical and economical radio frequency (RF) connection solution for wearable systems, since they can form detachable RF connection with suitable RF performance [21]- [23]. This leads to the idea of making specific radiation elements detachable with snap-on buttons to achieve modular antenna designs, thus enabling passive reconfigurability of the overall system.…”

mentioning

confidence: 99%

A Modular Textile Antenna Design Using Snap-on Buttons for Wearable Applications

Chen

Kaufmann

Ranasinghe

et al. 2016

IEEE Trans. Antennas Propagat.

Self Cite

View full text Add to dashboard Cite

Authors and/or their employers shall have the right to post the accepted version of IEEE-copyrighted articles on their own personal servers or the servers of their institutions or employers without permission from IEEE, provided that the posted version includes a prominently displayed IEEE copyright notice (as shown in 8.1.9.B, above) and, when published, a full citation to the original IEEE publication, including a Digital Object Identifier (DOI). Authors shall not post the final, published versions of their articles.

show abstract

Paired Snap-On Buttons Connections for Balanced Antennas in Wearable Systems

Cited by 31 publications

References 17 publications

A battery-less and wireless wearable sensor system for identifying bed and chair exits in a pilot trial in hospitalized older people

A battery-less and wireless wearable sensor system for identifying bed and chair exits in a pilot trial in hospitalized older people

A Flexible 2.45-GHz Power Harvesting Wristband With Net System Output From −24.3 dBm of RF Power

A Modular Textile Antenna Design Using Snap-on Buttons for Wearable Applications

Contact Info

Product

Resources

About