. By detecting exhaled moisture directly on the philtrum, the sensor exhibits a rapid response time of 1 s and a recovery time between 2 and 10 s. A direct-spun nanofiber-based wiring strategy ensures robust integration, accommodating a 10 mm displacement under 10.4 MPa of stress without failure. Driven by a compact 3 g circuit with 20 mW of power consumption, the system supports continuous wireless data transmission for over 7.3 h. During vigorous exercise and sleep, the BSET reliably monitored respiratory dynamics, identifying 10-20 s apnea events and enabling multiparameter analysis of breathing frequency and exhalation intensity. This lightweight system establishes a scalable and clinically relevant solution for continuous respiratory surveillance.

Internet of Things (IoT) devices are increasingly deployed in radio frequency-challenging environments such as underground, underwater, and high electromagnetic interference scenarios. In smart agriculture, for instance, multiple distributed IoT controllers require wireless power supply in the form of load-independent constant voltage (CV), while a multiparameter IoT sensor needs to be capable of transmitting data across varying distances. To address these requirements, this article presents a novel magnetic induction-based wireless power and data transfer system. The proposed system adopts a domino structure to support multiple devices. A unified load-utilized technique is then employed to realize individual CV output and data transmission, while the newly proposed load-resonator interleaved strategy enables these two functions to operate simultaneously within the same system. Theoretical analysis is conducted, and validation is provided through experimental measurements using 5- to 8-stage configurations under both in electronic and ex situ (laboratory soil) conditions. Results demonstrate the delivery of 160 mW CV power to each of three IoT controllers, along with successful 6 kbps data transfer from the sensor to all devices simultaneously, whereas failures occur when the proposed strategy is not applied.

This paper presents a reconfigurable bidirectional wireless power and data transceiver (RB-WPDT) integrated circuit (IC) for wearable biomedical applications. The proposed transceiver can be reconfigured as a differential class-D power amplifier or a full-wave rectifier depending on the mode signal to facilitate power transfer between devices. Additionally, the RB-WPDT system supports full-duplex (FD) data transmission via a single inductive link, enabling real-time control and monitoring between devices. The proposed FD method utilizes frequency shift-keying pulse-width modulation (FSK-PWM) for downlink and load shift-keying (LSK) for uplink, achieving simultaneous bidirectional data transmission by ensuring that the FSK-PWM downlink and LSK uplink data channels operate independently with minimal interference. The measured downlink and uplink data rates are 250 kb/s and 67 kb/s, respectively. The measured overall DC-to-DC efficiency is 49%, while the power delivered to the load (PDL) is 120 mW at a 5 mm distance. The proposed chip is fabricated using a 180-nm BCD CMOS process.

This letter introduces a novel battery charging solution for multiple wearable devices. Using conductive textile interwoven into clothing, our system provides the convenience of on-body charging and the capacity to charge multiple devices concurrently from a single charger. The uniqueness of our approach lies in its capability to achieve load-independent constant current (CC) and constant voltage (CV) charging using a minimalistic component configuration and permitting each device to independently control its charging mode. Empirical results confirm a variation of less than 5% for both CC and CV charging, whereas theoretical evaluations suggest the system's potential to be scaled up to support an infinite number of devices.

. By detecting exhaled moisture directly on the philtrum, the sensor exhibits a rapid response time of 1 s and a recovery time between 2 and 10 s. A direct-spun nanofiber-based wiring strategy ensures robust integration, accommodating a 10 mm displacement under 10.4 MPa of stress without failure. Driven by a compact 3 g circuit with 20 mW of power consumption, the system supports continuous wireless data transmission for over 7.3 h. During vigorous exercise and sleep, the BSET reliably monitored respiratory dynamics, identifying 10-20 s apnea events and enabling multiparameter analysis of breathing frequency and exhalation intensity. This lightweight system establishes a scalable and clinically relevant solution for continuous respiratory surveillance.

Internet of Things (IoT) devices are increasingly deployed in radio frequency-challenging environments such as underground, underwater, and high electromagnetic interference scenarios. In smart agriculture, for instance, multiple distributed IoT controllers require wireless power supply in the form of load-independent constant voltage (CV), while a multiparameter IoT sensor needs to be capable of transmitting data across varying distances. To address these requirements, this article presents a novel magnetic induction-based wireless power and data transfer system. The proposed system adopts a domino structure to support multiple devices. A unified load-utilized technique is then employed to realize individual CV output and data transmission, while the newly proposed load-resonator interleaved strategy enables these two functions to operate simultaneously within the same system. Theoretical analysis is conducted, and validation is provided through experimental measurements using 5- to 8-stage configurations under both in electronic and ex situ (laboratory soil) conditions. Results demonstrate the delivery of 160 mW CV power to each of three IoT controllers, along with successful 6 kbps data transfer from the sensor to all devices simultaneously, whereas failures occur when the proposed strategy is not applied.

This paper presents a reconfigurable bidirectional wireless power and data transceiver (RB-WPDT) integrated circuit (IC) for wearable biomedical applications. The proposed transceiver can be reconfigured as a differential class-D power amplifier or a full-wave rectifier depending on the mode signal to facilitate power transfer between devices. Additionally, the RB-WPDT system supports full-duplex (FD) data transmission via a single inductive link, enabling real-time control and monitoring between devices. The proposed FD method utilizes frequency shift-keying pulse-width modulation (FSK-PWM) for downlink and load shift-keying (LSK) for uplink, achieving simultaneous bidirectional data transmission by ensuring that the FSK-PWM downlink and LSK uplink data channels operate independently with minimal interference. The measured downlink and uplink data rates are 250 kb/s and 67 kb/s, respectively. The measured overall DC-to-DC efficiency is 49%, while the power delivered to the load (PDL) is 120 mW at a 5 mm distance. The proposed chip is fabricated using a 180-nm BCD CMOS process.

This letter introduces a novel battery charging solution for multiple wearable devices. Using conductive textile interwoven into clothing, our system provides the convenience of on-body charging and the capacity to charge multiple devices concurrently from a single charger. The uniqueness of our approach lies in its capability to achieve load-independent constant current (CC) and constant voltage (CV) charging using a minimalistic component configuration and permitting each device to independently control its charging mode. Empirical results confirm a variation of less than 5% for both CC and CV charging, whereas theoretical evaluations suggest the system's potential to be scaled up to support an infinite number of devices.

and the lowest system complexity using 1-bit ADC. In addition, we have demonstrated a reduction in charging time by at least 44.4% compared to conventional CC/CV methods, validating the effectiveness of our system's BIR compensation. The compact size and safety features of the proposed charging system make it promising for AIMDs, which have space-constrained environments.