The mechanism is described by which a passive UHF RFID tag coupled with a tuning circuit is integrated with a current transformer for sensing ac current in an electrical wire for smart power monitoring of individual appliances. A capacitance change in the tuning circuit results from a reverse bias voltage from the current transformer. The tuning circuit reactance is detected by a capacitance sensing RFID tag and the value is transmitted as a 5–bit sensor code which is directly related to the ac current drawn by an electrical load. The passive tag harvests energy and offers an innovative solution for energy management in future smart homes and for industry 4.0. As well as indicating current level, the technique can also be used to detect the ON and OFF state of an electrical device and is demonstrated to work for a rapidly switching load. The sensor is tuned for EPC Class 1 Generation 2 UHF RFID readers at 868 MHz.

We present a wirelessly powered ultraviolet-C (UVC) radiation-based disinfecting bandage for sterilization and treatment in chronic wound care and management. The bandage contains embedded low-power UV light-emitting diodes (LEDs) in the 265 to 285 nm range with the light emission controlled via a microcontroller. An inductive coil is seamlessly concealed in the fabric bandage and coupled with a rectifier circuit to enable 6.78 MHz wireless power transfer (WPT). The maximum WPT efficiency of the coils is 83% in free space and 75% on the body at a coupling distance of 4.5 cm. Measurements show that the UVC LEDs are emitting radiant power of about 0.6 mW and 6.8 mW with and without fabric bandage, respectively, when wirelessly powered. The ability of the bandage to inactivate microorganisms was examined in a laboratory which shows that the system can effectively eradicate Gram-negative bacteria, Pseudoalteromonas sp. D41 strain, on surfaces in six hours. The proposed smart bandage system is low-cost, battery-free, flexible and can be easily mounted on the human body and, therefore, shows great promise for the treatment of persistent infections in chronic wound care.

This study reports a design of an e-textile microstrip patch antenna for wireless sensing of the moisture content of a fabric substrate. The microstrip patch antenna with a proximity coupled feeding line is implemented on two layers of polyester felt substrate. The performance of the antennas in terms of the reflection coefficient S11 is measured, indicating that the resonance frequency of the antenna shifts to a lower frequency for moisture contents ranging from 20% to 100%. This is the result of a change in the dielectric constant and the loss tangent of the substrate material caused by the presence of moisture. The proposed moisture sensor exhibits high linearity and higher sensitivity than state-of-the-art textile-based antenna sensors, and is suitable for a variety of applications such as sweat and wound monitoring.

Dual operations of AC current sensing and Bluetooth transmission using a reconfigurable slot antenna are described here. The novel current sensing setup comprises of a tunable antenna connected to a current transformer and AC/DC converter to create a smart AC current sensing mechanism. The tunable antenna consists of a double-layer slot antenna on a thin, flexible substrate with a tuning circuit consisting of capacitive-coupled biasing tracks on the backside. Capacitive coupling isolates circuits at DC while providing connectivity at radio frequency (RF). Tracks act as the capacitors for the tuning biasing circuit. A double-sided copper clad Mylar substrate is etched to produce the slot antenna on one side and the biasing circuit using inexpensive Varactor diodes on the other side. The antenna tunes over a wide frequency range of approximately 2:1. The antenna is able to sense currents by providing a frequency response when connected to the sensing system. The current sensing antenna can also detect the operational or non-operational states of the appliances and devices. This low-cost setup of antenna on a flexible substrate can assist in detecting the power and current monitoring in household electrical devices providing an energy-efficient solution while also operating as a transmitter via Bluetooth. The measured reflection coefficients and radiation patterns are in a good agreement with the simulated results and noticeably clear sensing of current is achieved.

This study explores the effect of different types of bandages on the performance of an epidermal antenna. Three identical dipole antennas are designed on three different types of bandages, and the measured reflection coefficients, S₁₁, show that the antennas resonate at the same frequency despite the different types of fabric bandages. However, the antennas resonance frequency shifts to a lower frequency when the antennas are mounted on the body. The transmission coefficient, S₂₁, over a 60 cm link with a standard RFID antenna is at least −30 dB, and −34 dB in free space and on the body, respectively, demonstrating that the antenna is suitable for communication and wireless RF power transfer in wearable applications.

Objectives: To develop and evaluate a wearable, garment-integrated transcutaneous electrical nerve stimulation (TENS) system for relieving osteoarthritis knee pain, emphasizing safety, usability, and readiness for home and clinical deployment. Methods: We designed an IEC 60601 compliant TENS system that embeds flexible electrodes into a close-fitting, machine-washable textile. A seven-day, home-based usability evaluation was conducted with 11 participants with osteoarthritis. Outcomes included self-reported pain (baseline vs. post-use) and usability metrics (ease of setup and comfort). The system received Medicines and Healthcare products Regulatory Agency (MHRA) and Health Research Authority (HRA) approvals for a subsequent clinical investigation. Results: Participants reported strong user acceptance, ease of use and comfort. Average pain decreased by 54.79% over the evaluation period, indicating a meaningful short-term analgesic benefit in a home setting. No serious adverse events were observed. Conclusion: Integrating electrodes into a wearable garment addresses key limitations of conventional adhesive-pad TENS, improving placement consistency, comfort, and ease of use while supporting safe operation under IEC 60601. These preliminary findings support the feasibility of garment-based TENS for osteoarthritis management at home and justify a follow-on clinical trial to rigorously quantify pain relief, functional outcomes, and user satisfaction in a larger cohort. Clinical impact: The use of a washable TENS garment, compliant with IEC 60601, resulted in reduced osteoarthritis pain in a home setting. Its integration into home care is facilitated by an easy to use device with reusable textile electrodes.