Jamal Abounasr

Wearable technology has increased interest in monitoring vital signs in various medical fields, especially breathing monitoring. However, existing methods to track breathing patterns face challenges, including lack of user comfort, robustness, system reliability, and data processing issues. Therefore, it is crucial to develop user-friendly and reliable wireless methods to overcome these challenges. In this paper, we present a new wireless communication platform for real-time breathing monitoring. The platform consists of a wearable stretching belt with an embroidered loop antenna-based sensor connected to a compact Bluetooth transmitter, with dimensions of 17.145 x 11.303 mm², placed on the abdomen. The proposed antenna-based sensor was designed to transmit data over wireless networks operating at a 2.4GHz frequency. Its sensing mechanism involves detecting a received signal strength indicator (RSSI) wirelessly transmitted by the antenna sensor, which is responsive to strain. Experimental results were conducted to track different breathing patterns from a male volunteer. The system was compared with a Biopac MP36, and the obtained results showed a strong correlation with the measured values. The proposed system demonstrates the ability to detect various breathing patterns, including eupnea, hypopnea, hyperpnea, and Biot’s respiration. Furthermore, its accuracy in detecting these breathing patterns highlights its potential for clinical applications, such as monitoring respiratory health in patients with sleep disorders or chronic respiratory conditions.

This paper presents a study on the repeatability of washing effects on two antenna-based sensors for breathing monitoring. One sensor is an embroidered meander antenna-based sensor integrated into a T-shirt, and the other is a loop antenna integrated into a belt. Both sensors were subjected to five washing cycles, and their performance was assessed after each wash. The embroidered meander antenna was specifically compared before and after washing to monitor a male volunteer’s different breathing patterns, that is, eupnea, apnea, hypopnea, and hyperpnea. Stretching tests were also conducted to evaluate the impact of mechanical deformation on sensor behavior. The results highlight the changes in sensor performance across multiple washes and stretching conditions, offering insights into the durability and reliability of these embroidered and loop antennas for practical applications in wearable health monitoring. The findings emphasize the importance of considering both washing and mechanical stress in the design of robust antenna-based sensors.

Breathing rate is a crucial vital sign for evaluating well-being and identifying underlying diseases related to the respiration system. This paper presents a fully stretchable triangular loop antenna-based sensor for real-time respiration monitoring. This antenna is integrated into a commercially available T-shirt, which is made of stretchable conductive ink printed on a Thermoplastic polyurethane (TPU) substrate. The sensing mechanism is influenced by shifts in the resonance frequency of a triangular loop antenna sensor, which occur due to thoracic and abdominal deformation during the breathing cycle of inspiration and expiration. The proposed system captures breathing patterns by detecting shifts in the resonance frequency, which are continuously recorded in real-time via Matlab. The Vector Network Analyzer (VNA) was connected to a remote PC via a LAN interface to store the breathing data on a PC host, facilitating data transfer over TCP/IP through the same LAN interface. The proposed antenna-based sensor stands out for its lightweight structure making it convenient to embed in clothing, and its ability to provide continuous monitoring of different breathing patterns including Eupnea, Bradypnea, Tashypnea, Ataxic, Sighing, and Biot’s breathing. The proposed system was tested through experimental measurements, and the obtained results matched well with the standard breathing patterns provided by the World Health Organization.