Design of PIFA With Metamaterials for Body-SAR Reduction in Wearable Applications

Kwak, Se Hyun; Sim, Donggyu; Kwon, Jong Hwa; Yoon, Young Joong

doi:10.1109/temc.2016.2593493

Cited by 85 publications

(47 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently, metamaterial surfaces have been widely used for SAR reduction of wearable antennas, because of its low cost and easy installation . These surfaces are artificially designed structures, which do not exist in nature and have the characteristics of high electromagnetic surface wave impedance.…”

Section: Introductionmentioning

confidence: 99%

“…Recently, metamaterial surfaces have been widely used for SAR reduction of wearable antennas, because of its low cost and easy installation. 20,21 These surfaces are artificially designed structures, which do not exist in nature and have the characteristics of high electromagnetic surface wave impedance. These structures are capable of suppressing the propagation of surface currents/waves within a particular frequency band (bandgap), and are recommended as a ground plane to improve the performance of the antennas.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Design and comparative analysis of conventional and metamaterial‐based textile antennas for wearable applications

Ali¹,

Ullah²,

Shafi

et al. 2019

Int J Numerical Modelling

View full text Add to dashboard Cite

In this paper, four different models of a 2.4 GHz flexible microstrip patch wearable antenna are designed and analyzed. The basic geometry of the radiating element of the antennas is a rectangular patch and is backed by conventional, mushroom‐type, slotted, and spiral electromagnetic band gap (EBG) ground planes. A 3‐mm‐thick wash cotton textile is used as a substrate material in the design of the antennas as well as EBG surfaces. An electro‐textile (Zelt) is used as a conductive material for the proposed antennas. The performance of these antennas is analyzed in terms of return loss, gain, bandwidth efficiency, and specific absorption rate (SAR) using Computer Simulation Technology Microwave Studio (CST MWS). The designed antennas are further investigated for on and off body conditions under normal and bent states. The experimental results show that the antennas radiate with an adequate gain (5.72‐7.3 dB), bandwidth (65.43‐103.1 MHz), and efficiency (55.51%‐74.04%), depending on the type of the ground plane used. The antenna backed by the mushroom‐type EBG gives the smallest value of SAR (1.79 W/kg < 2 W/kg), which makes it a suitable candidate for body worn applications in the unlicensed industrial, scientific, and medical (ISM) band.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Design and comparative analysis of conventional and metamaterial‐based textile antennas for wearable applications

Ali¹,

Ullah²,

Shafi

et al. 2019

Int J Numerical Modelling

View full text Add to dashboard Cite

show abstract

“…Meta‐surfaces due to their unique properties they proved useful in either absorbing energy in certain direction are reflecting back energy into certain direction to improve gain . Recent year's several attempts are being made to incorporate these metasurface (MS) based structures like artificial magnetic conductors, electromagnetic band gap structures, frequency selective surface (FSS), resonators, and some parasitic elements to redirect this backward energy to reduce the SAR for flexible antennas …”

Section: Introductionmentioning

confidence: 99%

Specific absorption rate reduction using metasurface unit cell for flexible polydimethylsiloxane antenna for 2.4 GHz wearable applications

Janapala

Nesasudha

Neebha

et al. 2019

Int J RF Microw Comput Aided Eng

View full text Add to dashboard Cite

This article presents the design of a polydimethylsiloxane based flexible antenna for body worn applications. In order to reduce the specific absorption rate (SAR) metasurface (MS) based unit cell is proposed. Copper foil of thickness 3 mil considered for conducting layers. The proposed antenna is designed with leaf structure and covers the WLAN ISM band 2.4 GHz without metasurface (NMS) and with metasurface (WMS) unit cell. The MS unit cell at the backside of the antenna does not cover the entire antenna but only a portion of it where the backward energy is highly concentrated. This yields better result in reducing the SAR with a very compact sized MS unit cell. This MS structure improves the gain of an antenna and also reduces the SAR, by directing the radiating energy in opposite direction from the human user. The proposed antenna NMS has a simulated SAR value of 2.53 W/kg at 2.4 GHz over volume of 1 g of tissue, whereas WMS it is reduced to 1.53 W/kg. The comparative analysis of the proposed antenna presented with the help of performance matrices like reflection coefficient, SAR, gain, and radiation patterns.

show abstract

“…Currently, smartwatch antennas are positioned under the LCD panel or around the main body of the watch (e.g., in an Apple Watch), and WiFi band and Bluetooth antennas are inserted into space of limited size. A multiantenna design cannot be employed due to the limited volume of the host object [1][2][3]. Several studies on MIMO antennas have proposed the implementation of the antenna on the host object of a smart watch [4][5][6]; however, those studies were conducted for the 2.4 GHz band and did not specify the antenna efficiency.…”

Section: Introductionmentioning

confidence: 99%

Watchstrap-Embedded Four-Element Multiple-Input–Multiple-Output Antenna Design for a Smartwatch in 5.2–5.8 GHz Wireless Applications

Sun

2018

International Journal of Antennas and Propagation

View full text Add to dashboard Cite

This paper presents a compact four-element multiple-input-multiple-output (MIMO) antenna design operating within the WiFi 802.11 ac bands (5.2-5.84 GHz) for a smartwatch. The antenna is fabricated using a polyamide substrate and embedded into the strap of a smartwatch model; the strap is created using three-dimensional etching of plastic materials. The four-element MIMO antenna is formed by four monopole antennas, has a simple structure, and is connected to the system ground plane of the smartwatch. Due to the stub and notched block between two antennas and the slit in the system ground, the four-element MIMO antenna exhibits favorable isolation. Moreover, the envelope correlation coefficient of the antennas is considerably lower than 0.005 in the operating band. The measured −6 dB impedance bandwidths of the four elements of the antenna (Ant1-Ant4) with the human wrist encompass the WiFi 802.11 ac range of 5.2-5.84 GHz; moreover, an isolation of more than 20 dB is achieved. The measured antenna efficiency with and without a phantom hand are 45%-55% and 93%-97%, respectively.

show abstract

Design of PIFA With Metamaterials for Body-SAR Reduction in Wearable Applications

Cited by 85 publications

References 7 publications

Design and comparative analysis of conventional and metamaterial‐based textile antennas for wearable applications

Design and comparative analysis of conventional and metamaterial‐based textile antennas for wearable applications

Specific absorption rate reduction using metasurface unit cell for flexible polydimethylsiloxane antenna for 2.4 GHz wearable applications

Watchstrap-Embedded Four-Element Multiple-Input–Multiple-Output Antenna Design for a Smartwatch in 5.2–5.8 GHz Wireless Applications

Contact Info

Product

Resources

About