Wireless charging is a technology of transmitting power through an air gap to electrical devices for the purpose of energy replenishment. The recent progress in wireless charging techniques and development of commercial products have provided a promising alternative way to address the energy bottleneck of conventionally portable battery-powered devices. However, the incorporation of wireless charging into the existing wireless communication systems also brings along a series of challenging issues with regard to implementation, scheduling, and power management. In this paper, we present a comprehensive overview of wireless charging techniques, the developments in technical standards, and their recent advances in network applications. In particular, with regard to network applications, we review the static charger scheduling strategies, mobile charger dispatch strategies and wireless charger deployment strategies. Additionally, we discuss open issues and challenges in implementing wireless charging technologies. Finally, we envision some practical future network applications of wireless charging.

Wireless Charging Technologies: Fundamentals, Standards, and Network Applications

We propose a compact planar ultrawideband (UWB) antenna with 3.4/5.5 GHz dual band-notched characteristics. The antenna consists of a beveled rectangular metal patch and a 50 Omega coplanar waveguide (CPW) transmission line. By etching two nested C-shaped slots in the patch, band-rejected filtering properties in the WiMAX/WLAN bands are achieved. The proposed antenna is successfully simulated, designed, and measured showing broadband matched impedance, stable radiation patterns and constant gain. An equivalent circuit model of the proposed antenna is presented to discuss the mechanism of the dual band-notched UWB antenna. A UWB antenna and a single band-notched one are also provided for references.

A Compact Ultrawideband Antenna With 3.4/5.5 GHz Dual Band-Notched Characteristics

This paper presents a novel broadband rectenna for ambient wireless energy harvesting over the frequency band from 1.8 to 2.5 GHz. First of all, the characteristics of the ambient radio-frequency energy are studied. The results are then used to aid the design of a new rectenna. A novel two-branch impedance matching circuit is introduced to enhance the performance and efficiency of the rectenna at a relatively low ambient input power level. A novel broadband dual-polarized cross-dipole antenna is proposed which has embedded harmonic rejection property and can reject the second and third harmonics to further improve the rectenna efficiency. The measured power sensitivity of this design is down to $- {\bf 35}\;{\bf dBm}$ and the conversion efficiency reaches 55% when the input power to the rectifier is $- {\bf 10}\;{\bf dBm}$ . It is demonstrated that the output power from the proposed rectenna is higher than the other published designs with a similar antenna size under the same ambient condition. The proposed broadband rectenna could be used to power many low-power electronic devices and sensors and found a range of potential applications.

A High-Efficiency Broadband Rectenna for Ambient Wireless Energy Harvesting

Reactive matching is extended to wide bandwidths using the impedance property of LC-ladder filters. In this paper, we present a systematic method to design wideband low-noise amplifiers. An SiGe amplifier with on-chip matching network spanning 3-10 GHz delivers 21-dB peak gain, 2.5-dB noise figure, and -1-dBm input IP3 at 5 GHz, with a 10-mA bias current.

A 3-10-Ghz low-noise amplifier with wideband LC-ladder matching network

With the development of wireless communication technology, the need for bandwidth is increasing continuously, and the growing need makes wireless spectrum resources more and more scarce. Cognitive radio (CR) has been identified as a promising solution for the spectrum scarcity, and its core idea is the dynamic spectrum access. It can dynamically utilize the idle spectrum without affecting the rights of primary users, so that multiple services or users can share a part of the spectrum, thus achieving the goal of avoiding the high cost of spectrum resetting and improving the utilization of spectrum resources. In order to meet the critical requirements of the fifth generation (5G) mobile network, especially the Wider-Coverage , Massive-Capacity , Massive-Connectivity , and Low-Latency four application scenarios, the spectrum range used in 5G will be further expanded into the full spectrum era, possibly from 1 GHz to 100 GHz. In this paper, we conduct a comprehensive survey of CR technology and focus on the current significant research progress in the full spectrum sharing towards the four scenarios. In addition, the key enabling technologies that may be closely related to the study of 5G in the near future are presented in terms of full-duplex spectrum sensing, spectrum-database based spectrum sensing, auction based spectrum allocation, carrier aggregation based spectrum access. Subsequently, other issues that play a positive role for the development research and practical application of CR, such as common control channel, energy harvesting, non-orthogonal multiple access, and CR based aeronautical communication are discussed. The comprehensive overview provided by this survey is expected to help researchers develop CR technology in the field of 5G further.

Full Spectrum Sharing in Cognitive Radio Networks Toward 5G: A Survey

Cet ensemble guide d'onde comprend un composant de reception (14) et un composant actif (12) electronique. Le composant de reception (14) comporte un guide d'onde (16), le guide d'onde (16) definissant une zone de propagation (40) s'etendant le long d'un axe de propagation, le guide d'onde (16) comprenant successivement, selon une direction verticale orthogonale a l'axe de propagation, une couche superieure (18), une couche intermediaire superieure, une couche centrale (22), une couche intermediaire inferieure (24), et une couche inferieure (26), le composant de reception (14) delimitant une cavite de reception (28) du composant actif (12), le composant actif (12) etant recu dans la cavite (28), la cavite (28) etant amenagee a travers la couche superieure (18) et la couche intermediaire superieure, et s'etendant selon la direction verticale depuis la couche centrale (22) jusqu'a une surface superieure (42A) de la couche superieure (18).

Ensemble guide d'onde et procede d'assemblage associe

Information and communications technology (ICT) plays a key role in higher education in improving the teaching process. Consequently, the environmental impacts associated with ICT are increasing, and innovative solutions must be deployed to reduce these impacts and increase students’ awareness. Single-board computers (SBCs) are promising because they rely on less materials and energy than desktop computers (PCs). But additional servers are required to perform large-scale computations. Hence, this paper aims at conducting comparative LCA between SBCs and PCs. The study is conducted in the context of a French engineering school with the following functional unit: “use 600 computers for 5 years in an engineering school.” Two scenarios are defined to fulfil this functional unit. Scenario 1 is the use of 600 PCs (current infrastructure), and scenario 2 is the use of 600 SBCs combined with 6 servers (alternative infrastructure). The analysis includes the materials manufacturing, assembly, packaging, transport, use and end-of-life of each device. Life cycle inventory (LCI) of the foreground systems was generated using a variety of sources: disassembly of computers, counting of electronic components, datasheets, estimations, etc. LCI of the background systems is taken from ecoinvent 3.5. The selected life cycle impact assessment methodology is ReCiPe 2016 midpoint, and computation of impacts is done with openLCA 1.10.3. Scenario 2 (SBCs + servers) generates 84 to 92% less impact than scenario 1 (PCs) in all categories. In terms of global warming, scenarios 1 and 2 generate 225 and 18 tCO2 eq per functional unit, respectively. This is explained by the large reduction in material and energy requirements for SBCs which is not counterbalanced by the servers. Equipment manufacturing accounts for the largest share of impacts in most categories for both scenarios (e.g., ~70% for global warming), followed by the use phase. This differs from the results found in the literature, as this study was conducted in the context of France, which has a low-carbon electricity mix. Our analysis has shown that SBCs combined with servers reduce the carbon footprint and other environmental impacts of ICT infrastructure for higher education. This study provides an example of low tech-oriented solution for students. Other prospective solutions (e.g., use of laptops) should be extensively studied in the future. From an LCA point of view, updating the inventory data related to background processes for electronic components is a necessary step forward to improve the certainty of the results. 

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Life cycle assessment of ICT in higher education: a comparison between desktop and single-board computers

A power limiter with high input power handling (24 dB over the input compression point) and sharp compression profile (less than 1.5 dB between the output 1-dB compression point and the output saturated power) in Ka-band (17.3 GHz; 20.2 GHz) is presented in this paper. Moreover, the circuit shows a low phase distortion (<3°) which make it suitable for use in an analog pre-processing linearizing system. This performances are obtained thanks to a novel architecture based on a power amplifier topology. This work presents the architecture along with the design methodology. Reliability is studied at high input power condition using the safe operation area from the technology provider. Then, a prototype is designed on 130 nm BiCMOS technology from STMicroelectronics, measured and compared to the simulation and the state of art.

High-Reliability Active Integrated Power Limiter with Sharp Compression Profile in Ka-Band in 130 nm SiGe Technology

This letter presents a transition from a top layer grounded coplanar waveguide (GCPW) to an inner layer air-filled substrate-integrated waveguide (AFSIW). Such type of transition is crucial for the interconnection of top layer surface-mounted radio-frequency integrated circuits (RFICs), toward the integration of complete microwave and millimeter-wave systems taking advantage of the low-cost and high-performance AFSIW technological platform. To fulfill the new space application needs, the proposed transition has been developed in the satellite downlink Ka-band ranging from 27.5 to 31 GHz. The structure is detailed with design guidance. For experimental evaluation, a back-to-back prototype has been fabricated and measured. In the operating frequency range, the proposed transition achieves a simulated and measured insertion loss (IL) as low as 0.135 ± 0.015 dB and 0.3 ± 0.18 dB, respectively.

Multilayer GCPW-to-AFSIW Transition for High-Performance Systems on Substrate

This paper proposes an innovative concept of spatial third-order intermodulation products (IMD3) filtering in millimeter-wave 5G phased arrays. This technique aims to relax the linearity constraints on the power amplifiers (PA) and thus power consumption. Implementation of independent control of the phase of IMD3 is proposed by using the nonlinear output capacitance of metal-oxide semi-conductors (MOS) amplifiers under phase-controlled second harmonic injection. The implemented control uses beamforming properties to perform spatial filtering of IMD3 product. A second harmonic injection on a power amplifier is proposed in STMicroelectronics CMOS065SOIMMW technology at 28 GHz. It shows phase control of IMD3 with a range of 35 degrees, allowing relaxation up to 17 dB on the linearity of large phased array power amplifiers. 

Anthony Ghiotto

Papers

Ensemble guide d'onde et procede d'assemblage associe

Life cycle assessment of ICT in higher education: a comparison between desktop and single-board computers

High-Reliability Active Integrated Power Limiter with Sharp Compression Profile in Ka-Band in 130 nm SiGe Technology

Multilayer GCPW-to-AFSIW Transition for High-Performance Systems on Substrate

Third Order Intermodulations Phase Shifting in Power Amplifiers for Spatial filtering in Multi-beam 5G mmW Phased Array