Millimeter Wave Antenna with Mounted Horn Integrated on FR4 for 60 GHz Gbps Communication Systems

A compact high gain and wideband millimeter wave (MMW) antenna for 60 GHz communication systems is presented. The proposed antenna consists of a multilayer structure with an aperture coupled microstrip patch and a surface mounted horn integrated on FR4 substrate. The proposed antenna contributes impedance bandwidth of 8.3% (57.4–62.4 GHz). The overall antenna gain and directivity are about 11.65 dBi and 12.51 dBi, which make it suitable for MMW applications and short-range communications. The proposed antenna occupies an area of 7.14 mm × 7.14 mm × 4 mm. The estimated efficiency is 82%. The proposed antenna finds application in V-band communication systems

High Gain and High Efficient Stacked Antenna Array with Integrated Horn for 60 GHz Communication Systems

In order to achieve wide bandwidth and high gain, we propose a stacked antenna structure having a microstrip aperture coupled feeding technique with a mounted Horn integrated on it. With optimized parameters, the single antenna element at a center frequency of 60 GHz, exhibits a wide impedance bandwidth of about 10.58% (58.9–65.25 GHz) with a gain and efficiency of 11.78 dB and 88%, respectively. For improving the gain, we designed a 2 × 2 and 4 × 4 arrays with a corporate feed network. The side lobe levels were minimized and the back radiations were reduced by making use of a reflector at λ/4 distance from the corporate feed network. The 2×2 array structure resulted in improved gain of 15.3 dB with efficiency of 83%, while the 4×4 array structure provided further gain improvement of 18.07 dB with 68.3% efficiency. The proposed design is modelled in CST Microwave Studio. The results are verified using HFSS, which are found to be in good agreement

Dielectric Resonator Nantennas for Optical Communication

Dielectric resonator antennas (DRA) are ceramic based materials that are nonmetallic in nature. They offer high permitivity values (εr: 10-100). DRAs? have made their mark in various applications specially in the microwave and millimeter wave (MMW) spectrum, and are making encouraging progress in the THz band, because of their low conduction losses and higher radiation efficiencies compared to their metallic counterparts. With the advancements in nano fabrication, metallic antennas designed in the THz band have taken an interest. These antennas are termed as optical antennas or nantennas. Optical antennas work by receiving the incident electromagnetic wave or light and focusing it on a certain point or hot spot. Since most of the antennas are metallic based with Noble metals as radiators, the conducting losses are huge. One solution that we offer in this work is to integrate the nantennas with DRs. Two different DR based designs, one triangular and other hexagonal, are presented. Both the antennas operate in the optical C-band window (1550 nm). We design, perform numerical analysis, simulate, and optimize the proposed DR nantennas. We also consider array synthesis of the proposed nantennas in evaluating how much directive the nantennas are for use in nano network applications

Compact dual-band implantable antenna for e-health monitoring

Single Molecule Spectroscopy and Superresolution Imaging XI 2018 -- 27 January 2018 through 28 January 2018 -- 136394This work presents a compact dual-band Planar Inverted F-antenna (PIFA) antenna useful for E-health monitoring and wireless sensors systems. The antenna operates in the Industrial Standard and Medical (ISM) and Wireless Medical Telemetry Service (WMTS) bands. It offers a compact size with dimensions 12.6 × 8.5 × 2.4 mm3. Two different simulators have been used to verify the results. The proposed antenna performs well in the presence of a bio-compatible insulator (BCI) material

State-of-the-Art Antenna Technology for Cloud Radio Access Networks (C-RANs)

The cloud radio access network (C-RAN) is one of the most efficient, low-cost, and energy-efficient radio access techniques proposed as a potential candidate for the implementation of next-generation (NGN) mobile base stations (BSs). A high-performance C-RAN requires an exceptional broadband radio frequency (RF) front end that cannot be guaranteed without remarkable antenna elements. In response, we present state-of-the-art antenna elements that are potential candidates for the implementation of the C-RAN’s RF front end. We present an overview of C-RAN technology and different types of planar antennas operating at the future proposed fifth-generation (5G) bands that may include the following: (i) ultra-wide band (UWB) (3–12 GHz), (ii) 28/38 GHz, and (iii) 60-GHz radio. Further, we propose different planar antennas suitable for the implementation of C-RAN systems. We design, simulate, and optimize the proposed antennas according to the desired specifications covering the required frequency bands. The key design parameters are calculated, analyzed, and discussed. In our research work, the proposed antennas are lightweight, low-cost, and easy to integrate with other microwave and millimeter-wave (MMW) circuits. We also consider different implementation strategies that can be helpful in the execution of large-scale multiple-input multiple-output (MIMO) networks

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Antennes optiques pour la récupération de l'énergie du rayonnement solaire

Recent years have witnessed an increased interest by the scientific community to acquire green and clean renewable sources of energy compared to traditional fossil fuels. Solar radiation is one particular abundant source of renewable energy that has been widely applied in vehicles, machines, and buildings, among others. There are generally two different ways in which solar energy is used – heat and electricity. The main motivation of this thesis work is to utilize that abundant source of energy in producing a small fraction of output DC voltage and current. Since the solar spectrum lies in the nano scale wavelengths or terahertz band, optical antennas as a novel nano fabrication technology will be used to capture and harvest the solar energy. Optical antennas have properties similar to their microwave counterparts, but the advantage they have is in terms of unprecedented means to tailor electromagnetic fields in all its aspects and applications. Therefore, with the aforementioned details, the main idea of this thesis is to capture the solar infrared radiation and utilize it for producing output DC voltage. The first part of this thesis is dedicated to understanding the working of radio frequency (RF) energy harvesting and presenting a rectenna design. The second part deals with the introduction and simulation of optical antennas based of dielectric resonators (DR) as they offer fewer losses at the THz band. Two different DR designs are proposed working at the center frequency of 193.5 THz (1550 nm wavelength). The third part discusses the main contribution to this work in terms of design, simulation and fabrication of a high gain and wideband Yagi-uda optical antenna. E-beam lithography technique is used to realize the proposed structure. Apart for the single element Yagi-uda design, various array configurations have been simulated with realization of a 100 x 100 elements array fabricated on a silicon substrate. To produce a certain amount of output voltage, two techniques were deployed in testing the realized Yagi-uda optical antenna array. The first technique involved integration of the Yagi-uda array with a commercial fermionic diode that produced output voltage of 0.15 V via excitation from a visible light and 0.52 V with direct excitation from a 1550 nm laser. The second technique is based on thermal dissipation among dissimilar metals producing an output voltage. Four different wavelength (532 nm, 650 nm, 940 nm and 1550 nm) lasers excited three realized nantenna designs. Among these designs, the maximum output voltage of 0.82 V was produced by the Yagi-uda array when excited via 1550 nm laser.Au cours des dernières années, la communauté scientifique s'est intéressée de plus en plus à l'acquisition de sources d'énergie renouvelables vertes et propres par rapport aux combustibles fossiles traditionnels. Le rayonnement solaire est une source particulièrement abondante d'énergie renouvelable qui a été largement utilisée dans les véhicules, les machines et les bâtiments, entre autres. Il y a généralement deux manières différentes d'utiliser l'énergie solaire: la chaleur et l'électricité. La principale motivation de ce travail de thèse est d'utiliser cette abondante source d'énergie pour produire une petite fraction de la tension et du courant continu de sortie. Puisque le spectre solaire se situe dans les longueurs d'onde à l'échelle nanométrique ou dans la bande térahertz, les antennes optiques seront utilisées comme une nouvelle technologie de nanotechnologie pour capter et récolter l'énergie solaire. Les antennes optiques ont des propriétés similaires à celles de leurs homologues micro-ondes, mais leur avantage réside dans des moyens sans précédent pour adapter les champs électromagnétiques dans tous leurs aspects et applications. Par conséquent, avec les détails mentionnés ci-dessus, l'idée principale de cette thèse est de capturer le rayonnement infrarouge solaire et l'utiliser pour produire une tension continue de sortie. La première partie de cette thèse est consacrée à la compréhension du fonctionnement de la collecte d'énergie par radiofréquence (RF) et à la présentation d'un concept de rectenna. La deuxième partie traite de l'introduction et de la simulation d'antennes optiques à base de résonateurs diélectriques (DR) car elles offrent moins de pertes à la bande THz. Deux conceptions de DR différentes sont proposées fonctionnant à la fréquence centrale de 193,5 THz (longueur d'onde 1550 nm). La troisième partie traite de la contribution principale à ce travail en termes de conception, simulation et fabrication d'une antenne optique Yagi-uda à haut gain et large bande. La technique de lithographie par faisceau d'électrons est utilisée pour réaliser la structure proposée. En dehors de la conception de l'élément unique Yagi-uda, diverses configurations de réseau ont été simulées avec la réalisation d'un réseau d'éléments 100 x 100 fabriqué sur un substrat de silicium. Pour produire une certaine quantité de tension de sortie, deux techniques ont été utilisées pour tester le réseau d'antennes optiques Yagi-uda. La première technique impliquait l'intégration du réseau Yagi-uda avec une diode fermionique du commerce qui produisait une tension de sortie de 0,15 V par excitation à partir d'une lumière visible et de 0,52 V par excitation directe à partir d'un laser à 1550 nm. La deuxième technique est basée sur la dissipation thermique entre des métaux dissemblables produisant une tension de sortie. Quatre lasers à longueurs d'onde différents (532 nm, 650 nm, 940 nm et 1550 nm) ont excité trois conceptions de nantenna réalisées. Parmi ces conceptions, la tension de sortie maximale de 0,82 V a été produite par le réseau Yagi-uda lorsqu'il est excité via un laser de 1550 nm

60 GHz beam-tilting coplanar slotted SIW antenna array

International audienceAbstract This article presents a 60 GHz coplanar fed slotted antenna based on substrate integrated waveguide (SIW) technology for beam-tilting applications. The longitudinal passive slots are fed via associated SIW holes adjacent to the coplanar feed while the main excitation is provided from the microstrip-to-SIW transition. The antenna array achieves an impedance bandwidth of 57–64 GHz with gains reaching to 12 dBi. The passive SIW slots are excited with various orientations of coplanar feeds and associated holes covering an angular beam-tilting from −56° to +56° with an offset of 10° at the central frequency. The novelty of this work is; beam-tilting is achieved without the use of any active/passive phase shifters which improves the design in terms of losses and provide a much simpler alternative compared to the complex geometries available in the literature at the 60 GHz band

Hexagonal Dielectric Loaded Nantenna for Optical ITU-T C-Band Communication

International audienceAntennas designed with nano scale technologies, at optical frequencies, will be a corner stone in next generation nano communication links and networks. These optical antennas, operating in the THz regime of electromagnetic spectrum, will be applicable to fields including biomedical, environmental, military, and civilian communications. In this paper, authors propose and explore the potential benefits of designing a hexagonal dielectric loaded nantenna (HDLN) at a center frequency of 193.5 THz using CST Microwave Studio. The nantenna consists of Silver 'Ag' as partial ground plane, a top and bottom 'SiO2' substrate and a 'Si' hexagon as dielectric fed by a 'Ag' nanostrip transmission line. The simulated nantenna achieves a wide impedance bandwidth of 3.7% from 190.9 THz to 198.1 THz and an end-fire directivity of 8 dBi, covering all the standard optical transmission window at the ITU-T optical communication 1550 nm C-band