scholarly journals A 2.45 GHz FSS Loaded Rectifying Antenna

2021 ◽  
Author(s):  
UDAYABHASKAR PATTAPU ◽  
Sushrut Das
Keyword(s):  
Wireless Power Transfer ◽  
Input Power ◽  
Maximum Efficiency ◽  
Power Transfer ◽  
Wireless Power ◽  
Free Response ◽  
Dc Voltage ◽  
Received Power ◽  
Polarization Insensitive ◽  
Antenna Impedance

Abstract In this paper the development of a rectenna system has been presented for 2.45 GHz wireless power transfer application. The receiving element of the rectenna (or the antenna) has been designed to possess spurious free response at least up to 10 GHz to improve the RF-DC conversion efficiency. It was found that the gain of the antenna is not sufficient for rectenna application. Therefore, to improve the gain of the antenna, it has been loaded with an angle and polarization insensitive FSS. The FSS loaded antenna achieved 7.7 dB gain, 85% radiation efficiency, and single operating band at 2.45 GHz; which is suitable for developing a rectenna for wireless power transfer. To convert the received RF energy into DC voltage a 2.45 GHz matched rectifier circuit has been designed. L-type matching network has been used to match the complex rectifier impedance with the 50 Ω antenna impedance. 1.52 V output voltage was obtained for 7 dBm input power and 3 kΩ load. Achieved maximum efficiency is 66.13% for 1.1 mW received power. It has been shown that the FSS loading of the antenna has the capacity of drastically improve the efficiency of the rectenna system.

scholarly journals Maximizing Transfer Efficiency with an Adaptive Wireless Power Transfer System for Variable Load Applications

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1417
Author(s):  
Jung-Hoon Cho ◽  
Byoung-Hee Lee ◽  
Young-Joon Kim
Keyword(s):  
Loading Condition ◽  
Wireless Power Transfer ◽  
Input Voltage ◽  
Transfer Efficiency ◽  
Maximum Efficiency ◽  
Variable Load ◽  
Power Transfer ◽  
Wireless Power ◽  
Variable Loading ◽  
Power Transfer Efficiency

Electronic devices usually operate in a variable loading condition and the power transfer efficiency of the accompanying wireless power transfer (WPT) method should be optimizable to a variable load. In this paper, a reconfigurable WPT technique is introduced to maximize power transfer efficiency in a weakly coupled, variable load wireless power transfer application. A series-series two-coil wireless power network with resonators at a frequency of 150 kHz is presented and, under a variable loading condition, a shunt capacitor element is added to compensate for a maximum efficiency state. The series capacitance element of the secondary resonator is tuned to form a resonance at 150 kHz for maximum power transfer. All the capacitive elements for the secondary resonators are equipped with reconfigurability. Regardless of the load resistance, this proposed approach is able to achieve maximum efficiency with constant power delivery and the power present at the load is only dependent on the input voltage at a fixed operating frequency. A comprehensive circuit model, calculation and experiment is presented to show that optimized power transfer efficiency can be met. A 50 W WPT demonstration is established to verify the effectiveness of this proposed approach.

scholarly journals Dual-Band RF Wireless Power Transfer System with a Shared-Aperture Dual-Band Tx Array Antenna

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3803
Author(s):  
Chan-Mi Song ◽  
Hong-Jun Lim ◽  
Son Trinh-Van ◽  
Kang-Yoon Lee ◽  
Youngoo Yang ◽  
...  
Keyword(s):  
Wireless Power Transfer ◽  
Transmission Efficiency ◽  
Array Antenna ◽  
Dual Band ◽  
Single Frequency ◽  
Power Transfer ◽  
Wireless Power ◽  
Beam Focusing ◽  
Received Power ◽  
Rf Wireless

In this paper, a dual-band RF wireless power transfer (WPT) system with a shared-aperture dual-band Tx array antenna for 2.4 and 5.8 GHz is proposed. The final configuration of the Tx array, which is made up of 2.4 GHz right-handed circular polarization (RHCP) patches and 5.8 GHz RHCP patches, is derived from the optimization of 2.4 and 5.8 GHz thinned arrays, ultimately to achieve high transmission efficiency for various WPT scenarios. The dual-band RF WPT Tx system including the Tx array antenna and a Tx module is implemented, and Rx antennas with a 2.4 GHz patch, a 5.8 GHz patch, and a dual-band (2.4 and 5.8 GHz) patch are developed. To validate the proposed dual-band RF WPT system, WPT experiments using a single band and dual bands were conducted. When transmitting RF wireless power on a single frequency (either 2.482 GHz or 5.73 GHz), the received power according to the distance between the Tx and Rx and the position of the Rx was measured. When the distance was varied from 1 m to 3.9 m and the transmitted power was 40 dBm, the received power value at 2.482 GHz and 5.73 GHz were measured and found to be 24.75–13.5 dBm (WPT efficiency = 2.985–0.224%) and 19.25–6.8 dBm (WPT efficiency = 0.841–0.050%), respectively. The measured results were in good agreement with the calculated results, and it is revealed that the transmission efficiency when wireless power is transmitted via beam-focusing increases more than that with conventional beam-forming. Furthermore, the dual-band WPT experiment proves that 2.482 GHz beam and 5.73 GHz beams can be formed individually and that their wireless power can be transmitted to a dual-band Rx or two different Rx.

scholarly journals Wireless power transfer system rigid to tissue characteristics using metamaterial inspired geometry for biomedical implant applications

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ramesh K. Pokharel ◽  
Adel Barakat ◽  
Shimaa Alshhawy ◽  
Kuniaki Yoshitomi ◽  
Costas Sarris
Keyword(s):  
Electromagnetic Waves ◽  
Wireless Power Transfer ◽  
Split Ring Resonator ◽  
Input Power ◽  
Power Transfer ◽  
Wireless Power ◽  
Biomedical Implant ◽  
Safety Regulations ◽  
Wireless Power Transfer System ◽  
Tissue Characteristics

AbstractConventional resonant inductive coupling wireless power transfer (WPT) systems encounter performance degradation while energizing biomedical implants. This degradation results from the dielectric and conductive characteristics of the tissue, which cause increased radiation and conduction losses, respectively. Moreover, the proximity of a resonator to the high permittivity tissue causes a change in its operating frequency if misalignment occurs. In this report, we propose a metamaterial inspired geometry with near-zero permeability property to overcome these mentioned problems. This metamaterial inspired geometry is stacked split ring resonator metamaterial fed by a driving inductive loop and acts as a WPT transmitter for an in-tissue implanted WPT receiver. The presented demonstrations have confirmed that the proposed metamaterial inspired WPT system outperforms the conventional one. Also, the resonance frequency of the proposed metamaterial inspired TX is negligibly affected by the tissue characteristics, which is of great interest from the design and operation prospects. Furthermore, the proposed WPT system can be used with more than twice the input power of the conventional one while complying with the safety regulations of electromagnetic waves exposure.

scholarly journals Asynchronous Focusing Time Reversal Wireless Power Transfer for Multi-users with Equal Received Power Assignment

IEEE Access ◽  
2021 ◽  
pp. 1-1
Author(s):  
Zhouming Yang ◽  
Deshuang Zhao ◽  
Jinlong Bao ◽  
Xin Ma ◽  
Lin Hu ◽  
...  
Keyword(s):  
Time Reversal ◽  
Wireless Power Transfer ◽  
Power Transfer ◽  
Power Assignment ◽  
Wireless Power ◽  
Received Power

scholarly journals Investigation and Modeling of Multi-Node Body Channel Wireless Power Transfer

Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 156
Author(s):  
Yuxuan Huang ◽  
Jian Zhao ◽  
Wenyu Sun ◽  
Huazhong Yang ◽  
Yongpan Liu
Keyword(s):  
High Efficiency ◽  
Power Transmission ◽  
Wireless Body Area Network ◽  
Wireless Power Transfer ◽  
Circuit Model ◽  
Area Network ◽  
Power Transfer ◽  
Wireless Power ◽  
Received Power ◽  
Simulation Parameters

Insufficient power supply is a huge challenge for wireless body area network (WBAN). Body channel wireless power transfer (BC-WPT) is promising to realize multi-node high-efficiency power transmission for miniaturized WBAN nodes. However, the behavior of BC-WPT, especially in the multi-node scenario, is still lacking in research. In this paper, the inter-degeneration mechanism of a multi-node BC-WPT is investigated based on the intuitive analysis of the existing circuit model. Co-simulation in the Computer Simulation Technology (CST) and Cadence platform and experiments in a general indoor environment verify this mechanism. Three key factors, including the distance between the source and the harvester, frequency of the source, and area of the ground electrodes, are taken into consideration, resulting in 15 representative cases for simulation and experiments studies. Based on the simulation parameters, an empirical circuit model to accurately predict the received power of multiple harvesters is established, which fits well with the measurement results, and can further provide guidelines for designs and research on multi-node BC-WPT systems.

Sign in / Sign up

Export Citation Format

Share Document