New Generation Wearable Antenna Based on Multimaterial Fiber for Wireless Communication and Real-Time Breath Detection

Abstract

Smart textiles and wearable antennas along with broadband mobile technologies have empowered the wearable sensors for significant impact on the future of digital health care. Despite the recent development in this field, challenges related to lack of accuracy, reliability, user’s comfort, rigid form and challenges in data analysis and interpretation have limited their wide-scale application. Therefore, the necessity of developing a new reliable and user friendly approach to face these problems is more than urgent. In this paper, a new generation of wearable antenna is presented, and its potential use as a contactless and non-invasive sensor for human breath detection is demonstrated. The antenna is made from multimaterial fiber designed for short-range wireless network applications at 2.4 GHz frequency. The used composite metal-glass-polymer fibers permits their integration into a textile without compromising comfort or restricting movement of the user due to their high flexibility, and shield efficiently the antenna from the environmental perturbation. The multimaterial fiber approach provided a good radio-frequency emissive properties, while preserving the mechanical and cosmetic properties of the garments. With a smart textile featuring a spiral shape fiber antenna placed on a human chest, a significant shift of the operating frequency of the antenna was observed during the breathing process. The frequency shift is caused by the deformation of the antenna geometry due to the chest expansion, and to the modification of the dielectric properties of the chest during the breath. We demonstrate experimentally that the standard wireless networks, which measure the received signal strength indicator (RSSI) via standard Bluetooth protocol, can be used to reliably detect human breathing and estimate the breathing rate in real time. The mobile platform takes the form of a wearable stretching T-shirt featuring a sensor and a detection base station. The sensor is formed by a spiral-shaped antenna connected to a compact Bluetooth transmitter. Breathing patterns were recorded in the case of female and male volunteers. Although the chest anatomy of females and males is different compared, the sensor’s flexibility allowed recording successfully a breathing rate of 0.3 Hz for the female and 0.5 Hz for the male, which corresponds to a breathing rate of 21 breaths per minutes (bpm) and 30 bpm, respectively.

All‐day wearable health monitoring system

“…To alleviate the problem of transmission signal reduction while maintaining the quality of service, F I G U R E 2 Main components required to implement an all-day monitoring system communication methods (adaptive channel coding, 27,28 transmission power scaling, 29 multiple-input multiple-output [MIMO], 30,31 novel transceiver architecture, 32 and QoSaware media access protocols 33 ) are reported. Technological advancements likewise smart textiles, 34,35 magnetic induction, [36][37][38][39] and body-coupled communications [40][41][42] also show potential. Smart textiles can reduce telecommunication power overhead and simplify networking schemes to improve market utilization by lowering costs, ensuring ease of cleaning, and encouraging standardization in manufacturing.…”

Glass: The carrier of light—Part II—A brief look into the future of optical fiber

“…To‐date, a remarkably wide range of previously impossible functions have been engineered into multimaterial fibers, including spatially resolved photodetection, 266 in‐fiber optoelectronics 267,268 . health monitoring, 269 and integrated multisensory functionalities 270,271 …”

“…267,268 health monitoring, 269 and integrated multisensory functionalities. 270,271 The future of smart fibers and wearable multifunctional fabrics, based on multimaterial fibers, is one of indubitable value and worthwhile continued efforts. Questions to be addressed include how diverse a range of multifunctionality can be engineered into the same fibers (and fabrics) and from how many dissimilar materials?…”

Recent Advances of Wearable Antennas in Materials, Fabrication Methods, Designs, and Their Applications: State-of-the-Art

“…Many review papers like [ 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 , 103 , 104 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 ] discussed wearable antennas thoroughly. There are many new high-performance con...…”