This paper discusses the energy encryption techniques for wireless power transfer (WPT). The WPT system can be categorized into three groups based on power transfer distances which are near-, medium-, and far-fields. Near-field is wireless power transfer within short distance while medium-field is the wireless power transfer with range more than short distance but not more than far field distance. In the near-field, contactless techniques such as inductive coupling and capacitive coupling are employed in WPT. In the medium-field WPT, a magnetic resonant coupling approach is employed. Electromagnetic radiation is used in the far-field WPT. Energy encryption is crucial in ensuring that electricity is delivered to the intended recipient. The energy encryption methods used in the WPT system are therefore reviewed in this study. A study of several techniques reveals that the distance, effectiveness, and quantity of receivers are the primary determinants of the most appropriate energy.
This paper discusses the energy encryption techniques for wireless power transfer (WPT). The WPT system can be categorized into three groups based on power transfer distances which are near-, medium-, and far-fields. Near-field is wireless power transfer within short distance while medium-field is the wireless power transfer with range more than short distance but not more than far field distance. In the near-field, contactless techniques such as inductive coupling and capacitive coupling are employed in WPT. In the medium-field WPT, a magnetic resonant coupling approach is employed. Electromagnetic radiation is used in the far-field WPT. Energy encryption is crucial in ensuring that electricity is delivered to the intended recipient. The energy encryption methods used in the WPT system are therefore reviewed in this study. A study of several techniques reveals that the distance, effectiveness, and quantity of receivers are the primary determinants of the most appropriate energy.
Wireless power transfer (WPT) technology has received much attention due to its flexibility and safety, becoming an important area of research and development for various applications. However, conventional WPT systems are often constrained by the inherent properties of physical circuit components, leading to limitations in power density and transmission efficiency. The advent of high-temperature superconducting (HTS) materials offers a promising pathway to significantly enhance WPT performance by leveraging the nearly zero resistance and higher current-carrying capacity of HTS materials. This review comprehensively examines the state-of-the-art in HTS devices and HTS-based wireless power transfer (HTS-WPT) technology. By systematically analyzing the theoretical and experimental advances in HTS-WPT systems, this review aims to provide a comprehensive understanding of their advantages and limitations, offering insights for future research and practical implementations in various promising applications. • Superconducting materials and circuit components are thoroughly surveyed and discussed. • Research on HTS-WPT systems is comprehensively reviewed and evaluated. • Potential applications of HTS-WPT systems based on their characteristics are recommended. • Future research directions and limitations of HTS-WPT systems are revealed.
Secure and high-speed communication is a critical issue for wireless power transfer (WPT) system. In this paper, the elliptic curve cryptography (ECC) algorithm was introduced and compared with AES and RSA cryptographic algorithm. Besides, a WPT communication system was established by utilizing the ECC algorithm and OFDM technology. In order to prevent electromagnetic interference, an antenna coil with DD structure was designed and an experiment platform based on signal coupling mechanism was set up. Experimental results show that the established communication system can realize reliable communication between the primary side and the secondary side with algorithm processing time less than 281ms. Considering its moderate processing time and high reliability, the ECC algorithm and OFDM technology have a prospective future in the WPT communication systems.
Wireless information and power transfer (WIPT) enables more sustainable and resilient communications due to the fact that it avoids frequent battery charging and replacement. However, it also suffers from possible information interception due to the open nature of wireless channels. Compared to traditional secure communications, secrecy wireless information and power transfer (SWIPT) has several distinct characteristic features. Wireless power transfer may increase vulnerability to eavesdropping, since a power receiver as a potential eavesdropper usually has a shorter access distance than an information receiver. On the other hand, wireless power transfer can be exploited to enhance wireless security. This article reviews the security issues in various SWIPT scenarios, with an emphasis on revealing the challenges and opportunities for implementing SWIPT. Furthermore, we provide a survey on a variety of physical layer security techniques to improve secrecy performance. In particular, we propose to use massive MIMO techniques to enhance power transfer efficiency and secure information transmission simultaneously. Finally, we discuss several potential research directions to further enhance the security in SWIPT systems.
In this paper, we study the impact of various eaves-dropping attacks on the secrecy performance in wireless power transfer (WPT)-based secure multi-hop transmission. Since each node has a limited power supply, each node harvests energy from the power beacon before data transmission. After then, each node fully consumes the harvested energy for data transmission. Meanwhile, according to the nature of the wireless medium, eavesdroppers can overhear the confidential message at each hop. In order to exploit the relationship between network parameters and secrecy performance, we derive the closed-form expression for secrecy outage probability (SOP) with different eavesdropping attacks, respectively. From the numerical results, we show that the Monte-Carlo simulation and analysis results are tightly matched. Additionally, we evaluate and discuss the impact of the power beacon’s transmit power, the number of eavesdroppers, and time switching ratio on the secrecy performance.
Wireless communication is shaping the future of seamless and reliable connectivity of billions of devices. The communication sector in Qatar is mainly driven by rising demand of higher data rates and uninterrupted connectivity of wireless devices. Wireless fidelity (Wi-Fi), cellular telephone and computer interface devices (e.g. Bluetooth) are a few of the commonly used applications for wireless distribution of information in Qatar. According to analysts, strong growth of Islamic banking, increase in IT consolidation and increased adoption of mobility solutions are some of the key contributors to the growth of digital infrastructure in Qatar. Modernization of legacy infrastructure is another focal point of government of Qatar to enable e-government initiative in rural areas and Tier II/ III cities of Qatar which has long term effects in various domains such as health, electricity, water, heat, communication and trade. Considering this exponential rise of wireless communication in Qatar, a great deal of research is being done from the perspective of secure deployment of new wireless networks. There is also a growing demand to develop more energy-efficient communication techniques to reduce the consumption of fossil fuel without compromising the quality of experience of users. This is also beneficial for solving economic issues that cellular operators are faced with the ever growing number of users. Moreover, with the upcoming FIFA world cup in 2022, millions of dollars are being spent to enhance the capacity and security of existing and upcoming communication networks. However, with greater connectivity and ultimate functionality come several important challenges. The first challenge is the security of data or more specifically who has access to the data. The broadcast nature of wireless channels implies that the transmitted information signals are also received by nodes other than the intended receiver, which results in the leakage of information. Encryption techniques at higher layers are used to secure transmitted information. However, the high computational complexity of these cryptographic techniques consumes significant amount of energy. Moreover, secure secret key management and distribution via an authenticated third party is typically required for these techniques, which may not be realizable in a dense wireless networks. Therefore, a considerable amount of work has recently been devoted to information-theoretic physical layer security (PLS) as a secure communication technique which exploits the characteristics of wireless channels, such as fading, noise, and interferences. The varying nature of these factors causes randomness in the wireless channel which can be exploited to achieve security. The transmission of secret messages takes place when the receiver»s channel experiences less fading than the eavesdropper»s channel, otherwise transmission remains suspended. The second concern is regarding the limited lifetime of wireless devices, especially when massive amount of data needs to be collected and transferred across the network. This challenge can be addressed by innovative means of powering, and for small energy limited devices, this implies the use of energy harvesting (EH) techniques. In this context, the transfer of data and power over a common electromagnetic (EM) wave has gained significant research interest over the past decade. The technique which merges wireless information transfer (WIT) with wireless power transmission (WPT) is commonly termed as simultaneous wireless information and power transfer (SWIPT). However, SWIPT systems cannot be supported using conventional design of transmitter and receiver. To address this issue, two broad categories of receiver architectures have been proposed in SWIPT literature i.e. separated and integrated architecture. In separated receiver architecture, the information decoder and energy harvester act as dedicated and separate units. This although not only increases the cost of receiver but also increases the complexity of the hardware. In contrast, the integrated receiver architecture jointly processes the information and energy using a unified circuitry for both. This architecture reduces the cost and hardware complexity Our work attempts to address the aforementioned issues by evaluating secrecy performance and proposing practical secrecy enhancement scheme in EH wireless devices. In particular, we investigate PLS in SWIPT systems in the presence of multiple eavesdroppers. The secrecy performance of the SWIPT system is analyzed for Rician faded communication links. The security performance is analyzed for imperfect channel estimation, and both separated and integrated receiver architectures for the SWIPT system. We derive closed-form expressions of the secrecy outage probability and the ergodic secrecy rate for the considered scenario and validate the derived analytical expressions through extensive simulations. Our results reveal that an error floor appears due to channel estimation errors at high values of signal to noise ratio (SNR); such that outage probability cannot be further minimized despite an increase in the SNR of the main link. Moreover, the results show that largest secrecy rate can be achieved when the legitimate receiver is equipped with separated SWIPT receiver architecture and the eavesdroppers have an integrated SWIPT receiver architecture. It is also demonstrated that the power splitting factor at both legitimate receiver and at eavesdroppers play a prominent role in determining the secrecy performance of SWIPT. We prove that a larger power splitting factor is required to ensure link security for poor channel estimation. Finally, our work discusses transmit antenna selection and baseline antenna selection schemes to improve security. Therein, it is shown that transmit antenna selection outperforms baseline antenna selection. The results provided in this work can be readily used to evaluate the secrecy performance of SWIPT systems operating in the presence of multiple eavesdroppers.
Shortcut to adiabaticity (STA) techniques have the potential to drive a system beyond the adiabatic limits. Here, we present a robust and efficient method for wireless power transfer (WPT) between two coils based on the so-called transitionless quantum driving (TQD) algorithm. We show that it is possible to transfer power between the coils significantly fast compared to its adiabatic counterpart. The scheme is fairly robust against the variations in the coupling strength and the coupling distance between the coils. Also, the scheme is found to be reasonably immune to intrinsic losses in the coils.