Textile Antennas as Hybrid Energy-Harvesting Platforms (original) (raw)
Related papers
Textile Antenna for RF Energy Harvesting Fully Embedded in Clothing
— In the context of Wireless Body Sensor Networks for healthcare and pervasive applications, textile antennas allow an ubiquitous monitoring, communication, energy harvesting and storage. This paper presents a smart coat with a dual-band textile antenna for Radio Frequency (RF) energy harvesting, operating at GSM 900 and DSC 1800 bands, which is fully embedded in the garment. Results obtained before and after the integration of the antenna into the garment are compared. The gain obtained in the simulation is about 1.8 dBi and 2.06 dBi, with radiation efficiency of 82% and 77,6% for the lowest and highest operating frequency bands, respectively.
Smart Coat with a Textile Antenna for Electromagnetic Energy Harvesting
Proceedings of 2nd International Electronic Conference on Sensors and Applications, 2015
In the framework of Wireless Body Sensor Networks (WBSN) for healthcare and pervasive applications, the textile antennas add wearability to the ubiquitous monitoring, communication, energy harvesting and storage systems. Wearable antennas are the bridge for a non-obtrusive integration of communication sensors and equipment, extending the interaction of the communication system. The integration of electronic devices on clothing brings the question about how to feed them. The batteries are an obvious choice, but they are bulk and require frequent replacement or recharging. Also, nowadays, their short longevity is an ecological problem. Currently, radio frequency energy is broadcasted from billions of wireless transmitters and therefore it can be harvested from the ambient. Responding to this context, this paper presents a smart coat with an embedded dual-band textile antenna for electromagnetic energy harvesting, operating at GSM 900 and DSC 1800 bands. The results obtained before and after the integration of the antenna into the garment are compared. For the highest and lowest frequency operating bands, the simulated gain is around 2.06 dBi and 1.8 dBi, respectively. Also, the textile antenna shows a radiation efficiency of 82% for GSM 900 and 77,6% for DSC 1800.
Textile-Based Large Area RF-Power Harvesting System for Wearable Applications
IEEE Transactions on Antennas and Propagation, 2019
In this paper, we demonstrate flexible and lightweight textile-integrated rectenna-arrays for powering wearable electronic devices. We propose a method to exploit large clothingareas to integrate arrays consisting of 2×2 and 2×3 rectenna elements. Each element comprises of a patch antenna and a rectifier which are fabricated using embroidery of conductive thread on textile substrates. The rectifier used single-diode circuit configuration and showed an RF-to-DC conversion efficiency of 70% for an applied input RF-power of 8 dBm at its input port. We also present several tests to demonstrate the applicability of the rectenna array. Specifically, in boosted-Wi-Fi modality, a DC-power of 600 µW was collected at 10 cm from the source and 80 µW was collected at 60 cm from the source. These demonstrations show the proposed system's applicability for charging and powering low-power wearable electronic devices. Index Terms-conductive textiles, rectenna array, wireless power harvester, patch antenna, wearable applications D. Vital and S. Bhardwaj are with the Electrical and Computer Engineering
Energy-efficient off-body communication using textile antennas
Combining cutting-edge technologies and techniques with existing approaches, this book equips you with the tools and knowledge needed to develop new energy-efficient and environmentally friendly RFID (radio frequency identification) systems. As well as covering RFID basics, a wide range of new technologies is discussed, including biodegradable and recyclable material use, energy scavenging, passive and chipless architectures, RFID passive sensors, networked RFID and RFID sensors, organic electronic devices, textile electronics, and distributed and wide area electronics. Providing a clear description of how RFID technology can enable the evolution of the Internet of Things, the book guides you down the path to facing new challenges as we move towards ubiquitous sensing for smart environments and a networked society. This is an ideal guide for researchers in academia and industry, technical managers, and graduate students in RF and wireless communications.
Towards Wearable Wireless Power Harvesting using Clothing-Integrated Beamforming Structures
2022 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (AP-S/URSI)
High-gain wide-beam off-body wearable antennas are essential for efficient wearable RF energy harvesting (RFEH). Here, we report a 5.8-GHz reflector-backed Yagi-inspired antenna with over 2 dB gain and efficiency improvement over a conventional Yagi. Using the reflector, the end-fire patterns are redirected in the broadside off-body direction while maintaining a simulated 76% efficiency. To demonstrate the feasibility of high-gain RFEH, a beam-forming Rotman lens is designed with a relatively low insertion loss based on conventional fabrics with conductive surfaces designed to be implemented via the automated embroidery of conductive threads. This work is a stepping stone to clothing-integrated low-profile beamforming for sub-6 GHz 5G/6G applications.
2021 IEEE 20th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS), 2021
Wearable Radio Frequency (RF) rectennas do not require expensive or hazardous materials and can be easily integrated with conventional e-textiles. In this paper, we investigate the use of ultra-miniaturized wire-type monopole antennas for energy harvesting (EH) applications, as a method maximizing the effective collection area of a rectenna relative to its physical size, while not reducing the net DC output. The rectenna, operating in the 915 MHz band, is integrated with a simple carbon-based e-textile supercapacitor for direct energy conversion and storage. The integrated module is then demonstrated, for the first time, wirelessly-charging a Bluetooth Low Energy sensor node at over 1 m distance from a license-free Powercast transmitter. The 14.1 mF supercapacitor is charged using the e-textile rectenna filament in 83 s up to 4.14 V, from an incident power density of 23.9 µW/cm 2 and a timeaveraged efficiency over 40%, enabling the sensor node to sustain operation for 108 s after the wireless RF source is stopped. Compared to state-of-the-art RF energy harvesters, the proposed module achieves over five fold improvement in the RF to DC power harvesting efficiency normalized to the harvester's area.
Experimental Characterization of Wearable Antennas and Circuits for RF Energy Harvesting in WBANs
Field trials have been performed in Covilhã to identify the spectrum opportunities for radio frequency (RF) energy harvesting through power density measurements from 350 MHz to 3 GHz. Based on the identification of the most promising opportunities, a dual-band printed antenna was conceived, operating at GSM bands (900/1800), with gains of 1.8 and 2.06 dBi, and efficiency varying from 77.6 to 82%, for the highest and lowest operating frequency bands, respectively. In this paper, guidelines for the design of RF energy harvesting circuits and choice of textile materials for a wearable antenna are briefly discussed. Besides, we address the development and experimental characterization of three different prototypes of a five-stage Dickson voltage multiplier (with and without impedance matching circuit) responsible for RF energy harvesting. All the three prototypes (1, 2 and 3) can power supply the sensor node for RF received powers of 2 dBm, -3 dBm and -4 dBm, and conversion efficiencies of 6, 18 and 20%, respectively.
Powering E-Textiles Using a Single Thread Radio Frequency Energy Harvesting Rectenna
International Conference on the Challenges, Opportunities, Innovations and Applications in Electronic Textiles, 2021
Radio frequency energy harvesting (RFEH) and wireless power transfer (WPT) are increasingly seen as a method of enabling sustainable computing, as opposed to mechanical or solar EH WPT does not require special materials or resonators and can be implemented using low-cost conductors and standard semiconductor devices. This work revisits the simplest antenna design, the wire monopole to demonstrate the lowest-footprint, lowest-cost rectifying antenna (rectenna) based on a single Schottky diode. The antenna is fabricated using a single Litz-wire silk-coated thread, embroidered into a standard textile substrate. The rectifier is fabricated on a compact lowcost flexible printed circuit board (PCB) using ultra-thin polyimide copper laminates to accommodate low-footprint surface mount components. The antenna maintains its bandwidth across the 868/915 MHz license-free band on-and off-body with only −4.7 dB degradation in total efficiency in human proximity. The rectenna achieves up to 55% RF to DC efficiency with 1.8 V DC output, at 1 mW of RF power, demonstrating its suitability as a power-supply unit for ultra-low power e-textile nodes.
IEEE Open Journal of Antennas and Propagation, 2021
This paper presents a high-efficiency compact (0.016λ 2 0) textile-integrated energy harvesting and storage module for RF power transfer. A flexible 50 μm-thick coplanar waveguide rectenna filament is integrated with a spray-coated supercapacitor to realize an "e-textile" energy supply module. The meandered antenna maintains an S 11 < −6 dB inside and outside the fabric and in human proximity with a 2.3 dBi gain. The rectifier achieves a peak RF-DC efficiency of 80%, across a 4.5 k load, and a 1.8 V open-circuit voltage from −7 dBm. The supercapacitor is directly spray-coated on a cotton substrate using carbon and an aqueous electrolyte. When connected to the supercapacitor, the rectifier achieves over an octave half-power bandwidth. The textile-integrated rectenna is demonstrated charging the supercapacitor to 1.5 V (8.4 mJ) in 4 minutes, at 4.2 m from a license-free source, demonstrating a significant improvement over previous rectennas while eliminating power management circuitry. The integrated module has an end-to-end efficiency of 38% at 1.8 m from the transmitter. On-body, the rectenna's efficiency is 4.8%, inclusive of in-body losses and transient shadowing, harvesting 4 mJ in 32 seconds from 16.6 μW/cm 2. It is concluded that e-textile rectennas are the most efficient method for powering wearables from μW/cm 2 power densities.
2012
New wireless wearable monitoring systems worn by patients and caregivers require a high degree of reliability and autonomy. We show that active textile antenna systems may serve as robust platforms to deploy such wireless links, in the meanwhile being comfortable and invisible to the wearer, thanks to recent developments in the design process combined with dedicated signal processing techniques. The key idea is to exploit the large amount of real estate available in patients' and caregivers' garments to deploy multiple textile antennas each with a size large enough to make them efficient radiators when deployed on the body. The antenna area is then reused by positioning active electronics directly underneath and energy harvesters directly on top of the antenna patch, ensuring the autonomy of the module. Combining different antenna signals by means of low-power multi-antenna processing techniques then ensures good signal quality at low transmit power in all situations.