Comparative study of textile material characterization techniques for wearable antennas

Kaur

2023

Preprint

The aim of this paper is to investigate the possibilities of designing and fabricating a highly efficient and flexible wearable microstrip patch antenna operating at resonant frequency of 2.45 GHz. Copper Foil Tape (CFT) is used as a conducting medium in designing the patch and ground of antenna. While for designing the substrate, a graded profile based structures are made by combining two non-conducting fabrics i.e. Fleece-Curtain Cotton and Fleece-Polyester. The dielectric constant of these fabrics is measured with the help of ring resonator method. The proposed design models are simulated using CST simulator. To ensure the human body safety from antenna radiations in case of wearable applications, Specific Absorption Rate (SAR) is calculated on the simulated designs. Further some bending analysis of proposed antennas is also performed to ensure their applicability on different body parts like wrist, arm. Finally the proposed designs are fabricated and measured results are obtained using Agilent N5247A: A.09.90.02 VNA. TRL technique is used to calibrate the VNA with 3.5 SMA calibration kit.Simulated and measured results show good matching with each other in terms of resonant frequency, return loss, bandwidth and gain. The antenna designed using fleece-curtain cotton substrate achieved maximum bandwidth of 990 MHz, 2.22 dB gain and -34.99 dB value of S11 parameter. Voltage Standing Wave Ratio (VSWR) for all five antennas is less than 2. Hence the proposed antenna is a suitable candidate for wearable wireless applications.

Section: Literature Reviewmentioning

confidence: 99%

Flexible Wearable Microstrip Patch Antenna based on Graded Dielectric Substrate Profile for Wireless Applications

Kaur

2023

Preprint

“…Beberapa metode untuk melakukan ekstraksi karakteristik elektromagnetik material telah banyak diteliti. Salah satunya adalah dengan teknik coaxial probe, dan quarter wave open ended stub resonator [6], [7]. Namun kedua teknik tersebut memiliki struktur yang cukup kompleks dan membutuhkan biaya yang cukup besar.…”

Section: Pendahuluanunclassified

Untitled

Ryanu,

Jumria,

Siddik

et al. 2023

tektrika

Wearable antenna memiliki peran penting dalam WBAN (Wireless Body Area Network) sebagai komponen utama yang mendukung komunikasi on body. Penelitian ini berfokus kepada karakterisasi Material Under Test (MUT) dari bahan batik tradisional Indonesia dengan menggunakan metode ekstraksi sensor CSRR (Complementary split ring resonator). Respon frekuensi dan magnitude dari S21 digunakan untuk mengekstraksi permitivitas relatif bahan dan loss tangent bahan. Dari seluruh respon yang muncul kemudian dilakukan simulasi dan pengukuran antenna wearable dengan frekuensi kerja 2,4 GHz. Antena dengan hasil simulasi dan pengukuran yang paling mirip kemudian dipilih sebagai kandidat permitivitas relatif dan loss tangent bahan material. Dari 6 respon frekuensi yang muncul dari pengukuran sensor CSRR, nilai permitivitas relatif 2,083 dan loss tangent 0,144 memperoleh kemiripan yang baik antara simulasi dan pengukuran dengan tingkat akurasi sebesar 99,17%. Hasil akhir antena wearable yang diusulkan kemudian divalidasi juga untuk mengirimkan data denyut jantung menggunakan microcontroller ESP32 ke internet menggunakan access point Wifi frekuensi 2,4 GHz.

“…Conductive materials on the top and bottom layers of dielectric material have a high tolerance to deterioration due to mechanical deformation and resistance. The design of wearable antennas necessitates an understanding of the electromagnetic characteristics of the material that is utilized, such as permittivity, loss tangent, and substrate thickness [9]. Wearable materials are typically non-conductive and conductive textiles (electro-textiles).…”

Section: Introductionmentioning

confidence: 99%

Compact Flexible Planar Antennas for Biomedical Applications: Insight into Materials and Systems Design

Venkatachalam,

Jagadeesan,

Ismail

et al. 2023

Bioengineering

Planar antennas have become an integral component in modern biomedical instruments owing to their compact structure, cost effectiveness, and light weight. These antennas are crucial in realizing medical systems such as body area networks, remote health monitoring, and microwave imaging systems. Antennas intended for the above applications should be conformal and fabricated using lightweight materials that are suitable for wear on the human body. Wearable antennas are intended to be placed on the human body to examine its health conditions. Hence, the performance of the antenna, such as its radiation characteristics across the operating frequency bands, should not be affected by human body proximity. This is achieved by selecting appropriate conformal materials whose characteristics remain stable under all environmental conditions. This paper aims to highlight the effects of human body proximity on wearable antenna performance. Additionally, this paper reviews the various types of flexible antennas proposed for biomedical applications. It describes the challenges in designing wearable antennas, the selection of a flexible material that is suitable for fabricating wearable antennas, and the relevant methods of fabrication. This paper also highlights the future directions in this rapidly growing field. Flexible antennas are the keystone for implementing next-generation wireless communication devices for health monitoring and health safety applications.