The Experts below are selected from a list of 1206 Experts worldwide ranked by ideXlab platform
Johanna Virkki - One of the best experts on this subject based on the ideXlab platform.
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Embroidered UHF RFID Moisture Sensor Tag on Dishcloth Substrate
2018 IEEE International Symposium on Antennas and Propagation & USNC URSI National Radio Science Meeting, 2018Co-Authors: Xiaochen Chen, Leena Ukkonen, Han He, Johanna VirkkiAbstract:In this paper, we present an embroidered passive UHF RFID moisture sensor tag made of dishcloth and Conductive Yarn. This extremely cost-effective and environmentally friendly wireless sensor can be easily embedded into versatile structures. The initial read range of the sensor tag was 4.7 meters at 915 MHz. In this preliminary study, 10 drops of water were applied on the sensor part of the structure and the performance of the sensor tag was measured in office conditions after 5, 10, and 15 minutes. After 5 minutes and 10 minutes, the read range increased to 5.0 and 5.2 meters, respectively, due to the conductivity improvement of the antenna pattern and increased backscattered power from the tag. After that, the sensor tag started to dry and the read range started to decrease. After 15 minutes, the read range was back to 4.7 meters at 915 MHz. Based on these initial results, these tags show potential for low-cost identification and sensing solutions.
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Textile-Integrated Stretchable Structures for Wearable Wireless Platforms
2018 7th Electronic System-Integration Technology Conference (ESTC), 2018Co-Authors: Han He, Xiaochen Chen, Leena Ukkonen, Omid Mokhtari, Hiroshi Nishikawa, Johanna VirkkiAbstract:In this study, antennas for passive UHF RFID tags were created from a carbon-based stretchable conductor on a stretchable elastic band by brush-painting. The antennamicrochip interconnections were fabricated by two different ways: 1) by using already commonly reported gluing with Conductive silver epoxy and 2) by sewing the IC with Conductive Yarn. In addition to wireless evaluation of the fabricated RFID tags before and after stretching, we evaluated the effects of the interconnection type on tag performance and reliability. The achieved read ranges of around 1.5 meters are suitable for versatile textile-integrated RFID applications. Stretching causes permanent decrease to the tag read range but they remain functional even after 100 stretching cycles. In addition, the tags with the embroidered interconnections were found to be more reliable towards harsh stretching, compared to the tags with glued ICs. These initial results are very encouraging, considering the current trend towards more ecofriendly and cost-effective materials in electronics.
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Antennas and antenna-electronics interfaces made of Conductive Yarn and paint for cost-effective wearable RFIDs and sensors
2017 IEEE MTT-S International Microwave Symposium (IMS), 2017Co-Authors: Xiaochen Chen, Leena Ukkonen, Toni Björninen, Johanna VirkkiAbstract:We characterize textile antennas and antenna-electronics interconnections created by depositing Conductive paint and by embroidering with Conductive Yarn. Both approaches are based on affordable materials and enable single-step manufacturing of RFID tag on textiles. To achieve further material savings, our dipole antennas comprise of line-type structures instead of the commonly used metallized surfaces. To understand the electromagnetic properties of the antennas and to assess the quality of the conductors, both wireless measurements and electromagnetic field simulations were used. Overall, the tags made of the Conductive Yarn by embroidering were detectable at the distances of 5-to-6 meters in air and at 2 meters on the human body. Conductive paint yielded the corresponding distances of 3.5-to-4 meters and 1 meter, respectively.
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Cost- and time-effective sewing patterns for embroidered passive UHF RFID tags
2017 International Workshop on Antenna Technology: Small Antennas Innovative Structures and Applications (iWAT), 2017Co-Authors: Nicolas Brechet, Leena Ukkonen, Toni Björninen, Galatée Ginestet, Jeremie Torres, Elham Moradi, Johanna VirkkiAbstract:Embroidery is an efficient method for the fabrication of textile antennas. We studied the effects of reducing the amount of Conductive thread to achieve savings in material costs and the effects of the sewing pattern on the wireless performance of embroidered passive UHF RFID tags on two different fabric substrates. The antennas were sewed on cotton and polyamide fabrics, the ICs were attached to the embroidered antennas with a Conductive adhesive, and the wireless performance of the ready-made textile RFID tags was evaluated through measurements. The fabric parameters were found to have a major effect on the tag performance. Based on our results, significant amounts of time and Conductive Yarn can be saved in the embroidery of RFID tag antennas by only partially sewing the tag antenna.
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Electro-textile slotted patch antenna for wearable passive UHF RFID tags
2017 IEEE Radio and Wireless Symposium (RWS), 2017Co-Authors: Aruhan Liu, Zhigang Wei, Johanna Virkki, Xiaochen Chen, Leena Ukkonen, Toni BjörninenAbstract:We present the development and performance evaluation of wearable passive UHF RFID tags based on slotted patch antennas that are electromagnetically optimized for operation in the close proximity of the human body. The antennas are manufactured from an electro-textile material on a light-weight textile substrate. The required patch-to-ground interconnections are formed by means of sewing with Conductive Yarn and by wrapping the electro-textile over the edges of the antenna. Our results show that the slotted patch tags on 2 mm and 4 mm substrates achieve high read ranges of 3.2 and 8.2 m, respectively, when worn in the upper back.
Herbert Reichl - One of the best experts on this subject based on the ideXlab platform.
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fully untegrated ekg shirt based on embroidered electrical interconnections with Conductive Yarn and miniaturized flexible electronics
Wearable and Implantable Body Sensor Networks, 2006Co-Authors: Torsten Linz, Christine Kallmayer, Rolf Aschenbrenner, Herbert ReichlAbstract:A T-shirt has been developed that measures an EKG signal. This work is different to other research in the field as it focuses more on advanced interconnection and integration technologies for electronics in textiles rather than on the EKG shirt as functionality. It is the first application using an interconnection technology based on embroidery of Conductive Yarn that has been developed recently and published in T. Linz et al. (2005).
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BSN - Fully untegrated EKG shirt based on embroidered electrical interconnections with Conductive Yarn and miniaturized flexible electronics
International Workshop on Wearable and Implantable Body Sensor Networks (BSN'06), 2006Co-Authors: Torsten Linz, Christine Kallmayer, Rolf Aschenbrenner, Herbert ReichlAbstract:A T-shirt has been developed that measures an EKG signal. This work is different to other research in the field as it focuses more on advanced interconnection and integration technologies for electronics in textiles rather than on the EKG shirt as functionality. It is the first application using an interconnection technology based on embroidery of Conductive Yarn that has been developed recently and published in T. Linz et al. (2005).
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embroidering electrical interconnects with Conductive Yarn for the integration of flexible electronic modules into fabric
International Symposium on Wearable Computers, 2005Co-Authors: Torsten Linz, Christine Kallmayer, Rolf Aschenbrenner, Herbert ReichlAbstract:This paper shows how common embroidery can be used to integrate electronics into textile environment in a light and cost efficient way. A mechanism has been developed to embroider through flexible electronic modules using Conductive Yarn, thus creating an interconnection with other modules like sensors, batteries, textile keyboards, etc. Mold encapsulation has been found to improve the electrical contact and support the reliability of the whole system.
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ISWC - Embroidering electrical interconnects with Conductive Yarn for the integration of flexible electronic modules into fabric
Ninth IEEE International Symposium on Wearable Computers (ISWC'05), 2005Co-Authors: Torsten Linz, Christine Kallmayer, Rolf Aschenbrenner, Herbert ReichlAbstract:This paper shows how common embroidery can be used to integrate electronics into textile environment in a light and cost efficient way. A mechanism has been developed to embroider through flexible electronic modules using Conductive Yarn, thus creating an interconnection with other modules like sensors, batteries, textile keyboards, etc. Mold encapsulation has been found to improve the electrical contact and support the reliability of the whole system.
Hong Hu - One of the best experts on this subject based on the ideXlab platform.
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weavable Conductive Yarn based nico zn textile battery with high energy density and rate capability
ACS Nano, 2017Co-Authors: Yan Huang, Wing Shan Ip, Jie Zeng, Nga Sze Sea Yeung, Wing Sum Ng, Hongfei Li, Yukun Wang, Jie Yu, Hong HuAbstract:With intrinsic safety and much higher energy densities than supercapacitors, rechargeable nickel/cobalt–zinc-based textile batteries are promising power sources for next generation personalized wearable electronics. However, high-performance wearable nickel/cobalt–zinc-based batteries are rarely reported because there is a lack of industrially weavable and knittable highly Conductive Yarns. Here, we use scalably produced highly Conductive Yarns uniformly covered with zinc (as anode) and nickel cobalt hydroxide nanosheets (as cathode) to fabricate rechargeable Yarn batteries. They possess a battery level capacity and energy density, as well as a supercapacitor level power density. They deliver high specific capacity of 5 mAh cm–3 and energy densities of 0.12 mWh cm–2 and 8 mWh cm–3 (based on the whole solid battery). They exhibit ultrahigh rate capabilities of 232 C (liquid electrolyte) and 116 C (solid electrolyte), which endows the batteries excellent power densities of 32.8 mW cm–2 and 2.2 W cm–3 (based...
Leena Ukkonen - One of the best experts on this subject based on the ideXlab platform.
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Embroidered UHF RFID Moisture Sensor Tag on Dishcloth Substrate
2018 IEEE International Symposium on Antennas and Propagation & USNC URSI National Radio Science Meeting, 2018Co-Authors: Xiaochen Chen, Leena Ukkonen, Han He, Johanna VirkkiAbstract:In this paper, we present an embroidered passive UHF RFID moisture sensor tag made of dishcloth and Conductive Yarn. This extremely cost-effective and environmentally friendly wireless sensor can be easily embedded into versatile structures. The initial read range of the sensor tag was 4.7 meters at 915 MHz. In this preliminary study, 10 drops of water were applied on the sensor part of the structure and the performance of the sensor tag was measured in office conditions after 5, 10, and 15 minutes. After 5 minutes and 10 minutes, the read range increased to 5.0 and 5.2 meters, respectively, due to the conductivity improvement of the antenna pattern and increased backscattered power from the tag. After that, the sensor tag started to dry and the read range started to decrease. After 15 minutes, the read range was back to 4.7 meters at 915 MHz. Based on these initial results, these tags show potential for low-cost identification and sensing solutions.
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Textile-Integrated Stretchable Structures for Wearable Wireless Platforms
2018 7th Electronic System-Integration Technology Conference (ESTC), 2018Co-Authors: Han He, Xiaochen Chen, Leena Ukkonen, Omid Mokhtari, Hiroshi Nishikawa, Johanna VirkkiAbstract:In this study, antennas for passive UHF RFID tags were created from a carbon-based stretchable conductor on a stretchable elastic band by brush-painting. The antennamicrochip interconnections were fabricated by two different ways: 1) by using already commonly reported gluing with Conductive silver epoxy and 2) by sewing the IC with Conductive Yarn. In addition to wireless evaluation of the fabricated RFID tags before and after stretching, we evaluated the effects of the interconnection type on tag performance and reliability. The achieved read ranges of around 1.5 meters are suitable for versatile textile-integrated RFID applications. Stretching causes permanent decrease to the tag read range but they remain functional even after 100 stretching cycles. In addition, the tags with the embroidered interconnections were found to be more reliable towards harsh stretching, compared to the tags with glued ICs. These initial results are very encouraging, considering the current trend towards more ecofriendly and cost-effective materials in electronics.
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Antennas and antenna-electronics interfaces made of Conductive Yarn and paint for cost-effective wearable RFIDs and sensors
2017 IEEE MTT-S International Microwave Symposium (IMS), 2017Co-Authors: Xiaochen Chen, Leena Ukkonen, Toni Björninen, Johanna VirkkiAbstract:We characterize textile antennas and antenna-electronics interconnections created by depositing Conductive paint and by embroidering with Conductive Yarn. Both approaches are based on affordable materials and enable single-step manufacturing of RFID tag on textiles. To achieve further material savings, our dipole antennas comprise of line-type structures instead of the commonly used metallized surfaces. To understand the electromagnetic properties of the antennas and to assess the quality of the conductors, both wireless measurements and electromagnetic field simulations were used. Overall, the tags made of the Conductive Yarn by embroidering were detectable at the distances of 5-to-6 meters in air and at 2 meters on the human body. Conductive paint yielded the corresponding distances of 3.5-to-4 meters and 1 meter, respectively.
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Cost- and time-effective sewing patterns for embroidered passive UHF RFID tags
2017 International Workshop on Antenna Technology: Small Antennas Innovative Structures and Applications (iWAT), 2017Co-Authors: Nicolas Brechet, Leena Ukkonen, Toni Björninen, Galatée Ginestet, Jeremie Torres, Elham Moradi, Johanna VirkkiAbstract:Embroidery is an efficient method for the fabrication of textile antennas. We studied the effects of reducing the amount of Conductive thread to achieve savings in material costs and the effects of the sewing pattern on the wireless performance of embroidered passive UHF RFID tags on two different fabric substrates. The antennas were sewed on cotton and polyamide fabrics, the ICs were attached to the embroidered antennas with a Conductive adhesive, and the wireless performance of the ready-made textile RFID tags was evaluated through measurements. The fabric parameters were found to have a major effect on the tag performance. Based on our results, significant amounts of time and Conductive Yarn can be saved in the embroidery of RFID tag antennas by only partially sewing the tag antenna.
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Electro-textile slotted patch antenna for wearable passive UHF RFID tags
2017 IEEE Radio and Wireless Symposium (RWS), 2017Co-Authors: Aruhan Liu, Zhigang Wei, Johanna Virkki, Xiaochen Chen, Leena Ukkonen, Toni BjörninenAbstract:We present the development and performance evaluation of wearable passive UHF RFID tags based on slotted patch antennas that are electromagnetically optimized for operation in the close proximity of the human body. The antennas are manufactured from an electro-textile material on a light-weight textile substrate. The required patch-to-ground interconnections are formed by means of sewing with Conductive Yarn and by wrapping the electro-textile over the edges of the antenna. Our results show that the slotted patch tags on 2 mm and 4 mm substrates achieve high read ranges of 3.2 and 8.2 m, respectively, when worn in the upper back.
Davor Bonefačić - One of the best experts on this subject based on the ideXlab platform.
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Textile-based UHF RFID patch antenna with H-slot
12th European Conference on Antennas and Propagation (EuCAP 2018), 2018Co-Authors: Andrej Galoić, Branimir Ivšić, Davor Bonefačić, Juraj BartolićAbstract:The paper presents an analysis and fabrication of two wearable textile-based UHF patch antennas with H-shaped slot for RFID applications. Both prototypes are fabricated by embroidering Conductive Yarn into denim textile. The two antennas differ in embroidered grid density. Performance of the designed and fabricated textile antennas have been evaluated in terms of the antenna gain, input impedance and radiation patterns. The RFID chip was integrated with the antennas and read-range was tested.
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Wearable energy harvesting using wideband textile antennas
2016 10th European Conference on Antennas and Propagation (EuCAP), 2016Co-Authors: Andrej Galoić, Branimir Ivšić, Davor Bonefačić, Juraj BartolićAbstract:This paper presents an energy harvesting device for body centric sensor systems. The focus of collecting energy is put in the sensor far-field and in a large frequency bandwidth. The proposed device comprises of the logarithmic spiral textile antenna paired with a simple rectifier circuit. The antenna is designed and manufactured by embroidered Conductive Yarn into denim material. The antenna prototype has been tested. Several rectifier circuit topologies were simulated and the DC voltage at the rectifier output is obtained by simulation.
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Durability of Conductive Yarn used for manufacturing textile antennas and microstrip lines
2016 IEEE International Symposium on Antennas and Propagation (APSURSI), 2016Co-Authors: Branimir Ivšić, Andrej Galoić, Davor BonefačićAbstract:The mechanical properties and durability of various types of Conductive Yarns with different conductivities is analyzed. It is found that for some particular Yarn the process of making embroidered antennas needs to be modified, while alongside with conductivity, mechanical factors play major role in the antenna performance.
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Performance of embroidered Conductive Yarn in textile antennas and microstrip lines
2015 9th European Conference on Antennas and Propagation (EuCAP), 2015Co-Authors: Branimir Ivšić, Davor Bonefačić, Juraj BartolićAbstract:Influence of mechanical factors onto conductivity of the Conductive Yarn is studied. Several microstrip lines with various thread tensions are manufactured and compared in performance, to propose the strategy for efficient design and implementation of Conductive textiles. After washing the lines few times it was found that the conductivity vanishes.
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Embroidered textile logarithmic spiral antenna and its energy efficiency
2015 57th International Symposium ELMAR (ELMAR), 2015Co-Authors: Branimir Ivšić, Andrej Galoić, Davor BonefačićAbstract:The paper presents the parametric analysis of logarithmic spiral antenna which is followed with prototype design by embroidering Conductive Yarn into denim material. To match the antenna, exponentially tapered microstrip balun has been designed. The antenna exhibits stable properties across wide frequency band which makes it suitable for collecting the energy from outside sources.