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Article
Publication date: 1 November 2010

Carla Hertleer, Lieva Van Langenhove and Hendrik Rogier

The need for textile-based antennas originates from the development of smart textile systems that emerged in the nineties. The aim is to increase the functionality of textiles, in…

Abstract

The need for textile-based antennas originates from the development of smart textile systems that emerged in the nineties. The aim is to increase the functionality of textiles, in most cases, clothing, by adding electronic systems. This allows the monitoring of physical (such as heart or respiration rate) as well as environmental (such as humidity or temperature) parameters through an embedded sensor network. The availability of micro electronics on the one hand, and new textile materials on the other, stimulates this evolution. The development of integratable textile-based sensors and flexible interconnections is continuously ongoing research. Also, wireless data transfer from the garment to a nearby base-station requires new developments, especially when the flexibility and comfort of the garment needs to be preserved. This paper gives a detailed overview on performed research and reveals the feasibility, design and manufacturing process of textile-based antennas for this off-body communication. The antennas are low profile, breathable, light-weight and simple in structure which make them suitable to be unobtrusively embedded in apparel and provide flexibility and satisfactory performance.

Details

Research Journal of Textile and Apparel, vol. 14 no. 4
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 12 October 2023

Sasireka Perumalsamy, Kavya G. and Rajkumar S.

This paper aims to propose a two-element dual fed ultra-wideband (UWB) multiple input multiple output (MIMO) antenna system with no additional decoupling structures. The antenna…

Abstract

Purpose

This paper aims to propose a two-element dual fed ultra-wideband (UWB) multiple input multiple output (MIMO) antenna system with no additional decoupling structures. The antenna operates from 3.1 to 10.6 GHz. The antenna finds its usage in on-body wearable device applications.

Design/methodology/approach

The antenna system measures 63.80 × 29.80 × 0.7 mm. The antenna radiating element is designed by using a modified dumbbell-shaped structure. Jean cloth material is used as substrate. The isolation improvement is achieved through spacing between two elements.

Findings

The proposed antenna has a very low mutual coupling of S21 < −20 dB and impedance matching of S11 < −10 dB. The radiation characteristics are stable in the antenna operating region. It provides as ECC < 0.01, diversity gain >9.9 dB. The antenna offers low average specific absorption rate (SAR) of 0.169 W/kg. The simulated and measured results are found to be in reasonable match.

Originality/value

The MIMO antenna is proposed for on-body communication, hence, a very thin jean cloth material is used as substrate. This negates the necessity of additional material usage in antenna design and the result range indicates good diversity performance and with a low SAR of 0.169 W/kg for on-body performance. This makes it a suitable candidate for textile antenna application.

Details

Microelectronics International, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 30 March 2022

Mir Saeid Hesarian

In this article, the authors intended to analyze the shielding properties of a fabric frequency selective surface (FSS) structure to the basis of substrate fabric properties. For…

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Abstract

Purpose

In this article, the authors intended to analyze the shielding properties of a fabric frequency selective surface (FSS) structure to the basis of substrate fabric properties. For this purpose, the effect of the properties and structural parameters of the substrate fabric layer were analyzed on the shielding properties of the developed FSS.

Design/methodology/approach

The experimental and theoretical evaluations were done at the frequency band of 1,805–1,880 MHz and computer simulation technology (CST) was used in modeling. In experiments were developed the FSS structures by different fabrics as the substrate layers and the copper as the patch cells. The shielding properties of these samples were measured experimentally by the developed setup.

Findings

Confirming resonant frequencies, transmission coefficients, and the bandwidths results obtained from modeling and experiments show that the thickness, weight and interweaving structure parameters were affect the porosity of the substrate fabric. Porosity of the fabric moves the resonant frequency due to the changing of the dielectric properties of the fabric. Therefore, shielding properties of the FSS structure were affected by these parameters as the important characteristics of the substrate fabric. In addition, shielding properties of the samples (resonant frequencies and transmission coefficients) in different incident angles are not same in two modes of transverse electric and transfer magnetic.

Originality/value

The experimental results suggest that the introduced flexible FSS structures are suitable for shielding applications in the proposed frequency band.

Details

International Journal of Clothing Science and Technology, vol. 34 no. 5
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 25 February 2014

Minyoung Suh, Katherine E. Carroll, Edward Grant and William Oxenham

This research investigated the feasibility of using an inductively coupled antenna as the basis of applying a systems approach to smart clothing. In order to simulate real-life…

Abstract

Purpose

This research investigated the feasibility of using an inductively coupled antenna as the basis of applying a systems approach to smart clothing. In order to simulate real-life situations, the impact of the distortions and relative displacement of different fabric layers (with affixed antennas) on the signal quality was assessed. The paper aims to discuss these issues.

Design/methodology/approach

A spiral antenna was printed on different fabric substrates. Obstructive conditions of the inductively coupled fabric layers were investigated to find out how much influence these conditions had on transmission performance. Reflected signals and transmitted signals were observed, while fabric antennas were subjected to displacement (distance and dislocation) or deformation (stretching and bending). The threshold of physical obstacles was estimated based on statistical analyses.

Findings

The limits of physical conditions that enable proper wireless transmission were estimated up to ∼2 cm for both distance and dislocation, and ∼0.24 K for bending deformation. The antenna performance remained within an acceptable level of 20 percent transmission up to 10 percent fabric stretch. Based on well-established performance metrics used in clothing environment on the body, which employs 2-5 cm of ease, the results imply that the inductively coupled antennas may be suitable for use in smart clothing.

Originality/value

This research demonstrates that the use of inductively coupled antennas on multiple clothing layers could offer the basis of a new “wireless” system approach to smart clothing. This would not only result in performance benefits, but would also significantly improve the aesthetics of smart clothing which should result in new markets for such products.

Details

International Journal of Clothing Science and Technology, vol. 26 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 13 June 2023

Atul Varshney, Vipul Sharma, T. Mary Neebha and N. Prasanthi Kumari

This paper aims to present a low-cost, edge-fed, windmill-shaped, notch-band eliminator, circular monopole antenna which is practically loaded with a complementary split ring…

Abstract

Purpose

This paper aims to present a low-cost, edge-fed, windmill-shaped, notch-band eliminator, circular monopole antenna which is practically loaded with a complementary split ring resonator (CSRR) in the middle of the radiating conductor and also uses a partial ground to obtain wide-band performance.

Design/methodology/approach

To compensate for the reduced value of gain and reflection coefficient because of the full (complete) ground plane at the bottom of the substrate, the antenna is further loaded with a partial ground and a CSRR. The reduction in the length of ground near the feed line improves the impedance bandwidth, and introduced CSRR results in improved gain with an additional resonance spike. This results in a peak gain 3.895dBi at the designed frequency 2.45 GHz. The extending of three arms in the circular patch not only led to an increase of peak gain by 4.044dBi but also eliminated the notch band and improved the fractional bandwidth 1.65–2.92 GHz.

Findings

The work reports a –10dB bandwidth from 1.63 GHz to 2.91 GHz, which covers traditional coverage applications and new specific uses applications such as narrow LTE bands for future internet of things (NB-IoT) machine-to-machine communications 1.8/1.9/2.1/2.3/2.5/2.6 GHz, industry, automation and business-critical cases (2.1/2.3/2.6 GHz), industrial, society and medical applications such as Wi-MAX (3.5 GHz), Wi-Fi3 (2.45 GHz), GSM (1.9 GHz), public safety band, Bluetooth (2.40–2.485 GHz), Zigbee (2.40–2.48Ghz), industrial scientific medical (ISM) band (2.4–2.5 GHz), WCDMA (1.9, 2.1 GHz), 3 G (2.1 GHz), 4 G LTE (2.1–2.5 GHz) and other personal communication services applications. The estimated RLC electrical equivalent circuit is also presented at the end.

Practical implications

Because of full coverage of Bluetooth, Zigbee, WiFi3 and ISM band, the proposed fabricated antenna is suitable for low power, low data rate and wireless/wired short-range IoT-enabled medical applications.

Originality/value

The antenna is fabricated on a piece (66.4 mm × 66.4 mm × 1.6 mm) of low-cost low profile FR-4 epoxy substrate (0.54 λg × 0.54 λg) with a dielectric constant of 4.4, a loss tangent of 0.02 and a thickness of 1.6 mm. The antenna reflection coefficient, impedance and VSWR are tested on the Keysight technology (N9917A) vector network analyzer, and the radiation pattern is measured in an anechoic chamber.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 2 March 2015

Łukasz Januszkiewicz and Sławomir Hausman

The purpose of this paper is to compare the properties of simplified physical and corresponding numerical human body models (phantoms) and verify their applicability to path loss…

Abstract

Purpose

The purpose of this paper is to compare the properties of simplified physical and corresponding numerical human body models (phantoms) and verify their applicability to path loss modeling in narrowband and ultra-wideband on-body wireless body area networks (WBANs). One of the models has been proposed by the authors.

Design/methodology/approach

Two simplified numerical and two physical phantoms for body area network on-body channel computer simulation and field measurement results are presented and compared.

Findings

Computer simulations and measurements which were carried out for the proposed simplified six-cylinder model with various antenna locations lead to the general conclusion that the proposed phantom can be successfully used for experimental investigation and testing of on-body WBANs both in ISM and UWB IEEE 802.15.6 frequency bands.

Research limitations/implications

Usage of the proposed phantoms for the simulation/measurement of the specific absorption rate and for off-body channels are not within the scope of this paper.

Practical implications

The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies. The model is most suitable for wearable antenna radiation pattern simulation and measurement.

Social implications

Presented results facilitate applications of WBANs in medicine and health monitoring.

Originality/value

A new six-cylinder phantom has been proposed. The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 34 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 14 April 2023

Atul Varshney and Vipul Sharma

This paper aims to present the design development and measurement of two aerodynamic slotted X-bands back-to-back planer substrate-integrated rectangular waveguide (SIRWG/SIW) to…

Abstract

Purpose

This paper aims to present the design development and measurement of two aerodynamic slotted X-bands back-to-back planer substrate-integrated rectangular waveguide (SIRWG/SIW) to Microstrip (MS) line transition for satellite and RADAR applications. It facilitates the realization of nonplanar (waveguide-based) circuits into planar form for easy integration with other planar (microstrip) devices, circuits and systems. This paper describes the design of a SIW to microstrip transition. The transition is broadband covering the frequency range of 8–12 GHz. The design and interconnection of microwave components like filters, power dividers, resonators, satellite dishes, sensors, transmitters and transponders are further aided by these transitions. A common planar interconnect is designed with better reflection coefficient/return loss (RL) (S11/S22 ≤ 10 dB), transmission coefficient/insertion loss (IL) (S12/S21: 0–3.0 dB) and ultra-wideband bandwidth on low profile FR-4 substrate for X-band and Ku-band functioning to interconnect modern era MIC/MMIC circuits, components and devices.

Design/methodology/approach

Two series of metal via (6 via/row) have been used so that all surface current and electric field vectors are confined within the metallic via-wall in SIW length. Introduced aerodynamic slots in tapered portions achieve excellent impedance matching and tapered junctions with SIW are mitered for fine tuning to achieve minimum reflections and improved transmissions at X-band center frequency.

Findings

Using this method, the measured IL and RLs are found in concord with simulated results in full X-band (8.22–12.4 GHz). RLC T-equivalent and p-equivalent electrical circuits of the proposed design are presented at the end.

Practical implications

The measurement of the prototype has been carried out by an available low-cost X-band microwave bench and with a Keysight E4416A power meter in the microwave laboratory.

Originality/value

The transition is fabricated on FR-4 substrate with compact size 14 mm × 21.35 mm × 1.6 mm and hence economical with IL lie within limits 0.6–1 dB and RL is lower than −10 dB in bandwidth 7.05–17.10 GHz. Because of such outstanding fractional bandwidth (FBW: 100.5%), the transition could also be useful for Ku-band with IL close to 1.6 dB.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 20 October 2014

Zhongcheng Gui, Yongjun Deng, Zhongxi Sheng, Tangjie Xiao, Yonglong Li, Fan Zhang, Na Dong and Jiandong Wu

This paper aims to present a new intelligent wall-climbing welding robot system for large-scale steel structure manufacture, which is composed of robot body, control system and…

Abstract

Purpose

This paper aims to present a new intelligent wall-climbing welding robot system for large-scale steel structure manufacture, which is composed of robot body, control system and welding system.

Design/methodology/approach

The authors design the robot system according to application requirements, validate the design through simulation and experiments and use the robot in actual production.

Findings

Experimental results show that the robot system satisfies the demands of automatic welding of large-scale ferromagnetic structure, which contributes much to on-site manufacturing of such structures.

Practical implications

The robot can work with better quality and efficiency compared with manual welding and other semi-automatic welding devices, which can much improve large-scale steel structure manufacturing.

Originality/value

The robot system is a novel solution for large-scale steel structures welding. There are three major advantages: the robot body with reliable adsorption ability, large payload capability and good mobility which meet the requirements of welding; the control system with good welding seam tracking accuracy and intelligent automatic welding ability; and friendly human – computer interface which makes the robot easy to use.

Details

Industrial Robot: An International Journal, vol. 41 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 11 January 2023

Sirje Virkus, Janika Leoste, Kristel Marmor, Tiina Kasuk and Aleksei Talisainen

Telepresence robots (TPRs) are an emerging field of application and research that have received attention from various disciplines, including computer science, telehealth and…

Abstract

Purpose

Telepresence robots (TPRs) are an emerging field of application and research that have received attention from various disciplines, including computer science, telehealth and education. The purpose of this study is to conduct a bibliometric analysis of publications on TPR in the Web of Science database from 1980 to 2022 to gain a better understanding of the state of research on TPRs and explore the role of pedagogical and psychological aspects in this research.

Design/methodology/approach

The analysis of research publications on TPRs was made on the basis of papers published in the Web of Science database from 1980 to 2022. The following research questions were proposed: What are the main tendencies in publication years, document types, countries of origin, source titles, publication authors, affiliations of authors and the most cited articles related to TPRs? What are the main topics discussed in the publications from the perspective of psychology? What are the main topics discussed in the publications from the perspective of educational sciences?

Findings

The results indicate that it is in the computer science where most of the existing research has been conducted, whereas the interest in the psychology and educational science has been relatively low. The greatest regional contributor has been the USA, whereas the effort in the European Union lags behind. Research publications in psychology in the Web of Science database related to TPRs can be grouped into three broad thematic categories: features of TPRs, degree of social presence compared to physical presence or other mediated technologies and opportunities for using TPRs. The results suggest that from the perspective of psychology, TPRs are one of the approaches that could enable greater social presence in remote communication. Most of the analysed papers in educational sciences investigated the opportunities of using TPRs in various educational fields. However, while the findings of the studies indicated significant potential of TPRs for education, their acceptance for wider use is still challenged.

Research limitations/implications

The limitations of this research are that this study only analysed research papers in the Web of Science database and therefore only covers a limited number of scientific papers published in the field of psychology and educational sciences on TPRs. In addition, only publications with the term “telepresence robots” in the topic area of the Web of Science database were analysed. Therefore, several relevant studies are not discussed in this paper that are not reflected in the Web of Science database or were related to other keywords.

Originality/value

The field of TPRs has not been explored using a bibliographic analysis of publications in the Web of Science database from the perspective of psychology and educational sciences. The findings of this paper will help researchers and academic staff better understand the state of research on TPRs and the pedagogical and psychological aspects addressed in this research.

Details

Information and Learning Sciences, vol. 124 no. 1/2
Type: Research Article
ISSN: 2398-5348

Keywords

Article
Publication date: 1 May 1995

Martin Fojt

That someone can make you feel good is a quality in itself. There has been much talk within British government circles, for example, about “the feel‐goodfactor”, which is…

Abstract

That someone can make you feel good is a quality in itself. There has been much talk within British government circles, for example, about “the feel‐good factor”, which is constantly reminding us that it is just around the corner! Whether or not we can believe in this is another matter, but it certainly displays an awareness that making other people feel good can have positive benefits for you also. How this can be achieved will differ depending on your particular line of business. Having a good quality product does not in itself guarantee success as service quality must also be taken into account. This is where the feel‐good factor comes into play. It is all very well, for example, going to a restaurant to have a top‐class meal (in that the food was good), only to have it thrown at you. Quality, therefore, must not be seen as a separate entity, but more as a package deal.

Details

Library Review, vol. 44 no. 5
Type: Research Article
ISSN: 0024-2535

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