638 research outputs found

    Comparison of De-embedding Methods for Long Millimeter and Sub-Millimeter-Wave Integrated Circuits

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    National audienceThis paper compares several de-embedding methods over millimeter and sub-millimeter wave frequen-cies in integrated technology. These methods are compared for S-CPW transmission lines considered as device under test. From these comparisons we propose an effective way to de-embed transmission lines. A method called "Half-Thru de-embedding method" is especially discussed. The SCPW transmission line model and results are obtained from Ansys HFSS Simulations in BiCMOS 55-nm integrat-ed technology

    2020 NASA Technology Taxonomy: 2015 Technology Areas to 2020 Taxonomy Areas Crosswalk

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    To help users of the 2020 Taxonomy navigate changes from the 2015 Technology Area Breakdown Structure (TABS), this companion document provides a crosswalk between the 2015 Technology Areas (TAs) and the updated 2020 Taxonomy areas (TXs)

    Indoor wireless communications and applications

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    Chapter 3 addresses challenges in radio link and system design in indoor scenarios. Given the fact that most human activities take place in indoor environments, the need for supporting ubiquitous indoor data connectivity and location/tracking service becomes even more important than in the previous decades. Specific technical challenges addressed in this section are(i), modelling complex indoor radio channels for effective antenna deployment, (ii), potential of millimeter-wave (mm-wave) radios for supporting higher data rates, and (iii), feasible indoor localisation and tracking techniques, which are summarised in three dedicated sections of this chapter

    Méthodes de mesure pour l’analyse vectorielle aux fréquences millimétriques en technologie intégrée

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    This thesis focuses on the study of vectorial measurement methods for analysing microelectronic circuits in integrated technology at millimeter wave frequencies. Current calibration and de-embedding methods are less precise for successfully extracting the intrinsic parameters of devices and circuits at millimeter wave frequencies, while the targeted operating frequencies are above 100 GHz. This is especially true for the characterization of passive devices such as propagation lines. The initial motivation of this thesis work was to explain the exact origin of the additional loss measured in Slow-Wave Coplanar Waveguides (S-CPW) lines at millimeter wave frequencies. Was it a problem of raw measurement or a problem of de-embedding method, which underestimates the losses? Or was it a problem of insufficient modeling of the effects of adjacent cells, or even the creation of a perturbation mode of propagation?This work consists of estimating many de-embedding methods beyond 65 GHz and classifies these methods into three groups to be able to compare them in a meaningful way. This study was conducted in three phases.In the first phase, we compared all the de-embedding methods with known electrical model parasitics of pad/accessline. This phase identifies the optimal conditions to use and apply these de-embedding methods.In the second phase, the modeling of test structures is performed using a 3D electromagnetic simulator based on finite element method. This phase tested the robustness of the methods and considered an original de-embedding method called Half-Thru de-embedding method. This method gives comparable results to the TRL method, which remains the most effective method. However, it remains difficult to explain the origin of additional losses obtained in measured S-CPW line.A third modeling phase was analysed to take into account the measurement of probes and the adjacent cells near our device under test. More than 80 test structures were designed in AMS 0.35 μm CMOS technology to compare the different de-embedding methods and analyse the link with adjacent cells, measuring probes and perturbation mode of propagation.Finally, this work has identified a number of precautions to consider for the attention of microelectronic circuit designers wishing to characterize their circuit with precision beyond 110 GHz. It also helped to establish Half-Thru Method de-embedding method, which is not based on electrical model, unlike other methods.Cette thèse porte sur l’étude des méthodes de mesure pour l’analyse vectorielle des circuits microélectroniques en technologie intégrée aux fréquences millimétriques. Pour réussir à extraire les paramètres intrinsèques de circuits réalisés aux longueurs d'ondes millimétriques, les méthodes actuelles de calibrage et de de-embedding sont d'autant moins précises que les fréquences de fonctionnement visées augmentent au-delà de 100 GHz notamment. Cela est d’autant plus vrai pour la caractérisation des dispositifs passifs tels que des lignes de propagation. La motivation initiale de ces travaux de thèse venait du fait qu'il était difficile d'expliquer l’origine exacte des pertes mesurées pour des lignes coplanaires à ondes lentes (lignes S-CPW) aux fréquences millimétriques. Etait-ce un problème de mesure brute, un problème de méthode de-embedding qui sous-estime les pertes, une modélisation insuffisante des effets des cellules adjacentes, ou encore la création d'un mode de propagation perturbatif ?Le travail a principalement consisté à évaluer une dizaine de méthodes de de-embedding au-delà de 65 GHz et à classifier ces méthodes en 3 groupes pour pouvoir les comparer de manière pertinente. Cette étude s’est déroulée en 3 phases.Dans la première phase, il s’agissait de comparer les méthodes de de-embedding tout en maitrisant les modèles électriques des plots et des lignes d’accès. Cette phase a permis de dégager les conditions optimales d’utilisation pour pouvoir appliquer ces différentes méthodes de de-embedding.Dans la deuxième phase, la modélisation des structures de test a été réalisée à l’aide d’un simulateur électromagnétique 3D basé sur la méthode des éléments finis. Cette phase a permis de tester la robustesse des méthodes et d’envisager une méthode de-embedding originale nommée Half-Thru Method. Cette méthode donne des résultats comparables à la méthode TRL, méthode qui reste la plus performante actuellement. Cependant il reste difficile d'expliquer l'origine des pertes supplémentaires obtenues notamment dans la mesure des lignes à ondes lentes S-CPW.Une troisième phase de modélisation a alors consisté à prendre en compte les pointes de mesure et les cellules adjacentes à notre dispositif sous test. Plus de 80 structures de test ont été conçues en technologie AMS 0,35μm afin de comparer les différentes méthodes de de-embedding et d’en analyser les couplages avec les structures adjacentes, les pointes de mesure et les modes de propagation perturbatifs.Finalement, ce travail a permis de dégager un certain nombre de précautions à considérer à l’attention des concepteurs de circuits microélectroniques désirant caractériser leur circuit avec précision au-delà de 110 GHz. Il a également permis de mettre en place la méthode de de-embedding Half-Thru Method qui n'est basée sur aucun modèle électrique, au contraire des autres méthodes

    Phased-Array Antenna-in-Package Technology for Emerging Millimeter Wave Applications

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    The ever-increasing data rates for wireless technologies (e.g., satellite communications, fifth generation (5G) wireless communications, and automotive radars) has directed the interests towards millimeter wave (mm-Wave) technology that provides wider absolute bandwidth. Relatively small size of antennas at mm-Wave makes large-scale phased-array antenna (PAA) system a feasible solution to compensate for the path loss and alleviate the requirements of the RF transceiver front-ends at mm-Wave. Despite developments in the military applications for more than 50 years, active PAA systems have been costly for commercial applications. The high cost is mainly due to the discrete implementation of transmit/receive beamforming modules where III-V front-end monolithic microwave integrated circuits (MMICs) (GaAs or InP, or both) are assembled together with silicon-based chips used for address decoders, power management, and general digital control such as phase and gain setting and calibration. A paradigm shift happened when silicon-based phased arrays had been implemented starting with the work at Caltech using silicon-germanium (SiGe) bipolar CMOS (BiCMOS) and Si CMOS technologies. Silicon-based technologies (Si-CMOS and SiGe-BiCMOS) are not costly and are able to be produced in a large scale. On the other side, multilayer antenna-in-package (AiP) technology is currently the prevailing antenna and packaging technology for miscellaneous mm-Wave applications. These two technologies together make low-cost, low-power active PAA possible. A modular and scalable silicon-based phased-array AiP could be the building block for the development of large-scale mm-Wave PAA systems where hundreds to thousands of antenna elements are required in order to provide a reliable communication link. This approach not only ease the complexity of the system, but also makes the implementation of the system over any conformal geometry feasible. In this thesis, two different architectures for phased-array AiP are presented. The first architecture is a 4×4 active transmit phased-array AiP with polarization control at Ka-band. The second architecture is a 4×4 bi-directional antenna array with integrated passive beamformer with left-handed circular polarization (LHCP) radiation. In chapter II, a 4×4 active transmit phased-array AiP with polarization control at Ka-band is discussed. Silicon-based active transmit phased-array AiP is able to realize any kind of polarization including linear and circular polarization besides providing relatively high effective isotropic radiated power (EIRP). The proposed active AiP is modular and scalable and is able to be employed as the unit cell for a large-scale phased-array antenna system. It consists of 16 dual- linearly polarized cavity-backed patch antennas, four 8-channel active beamformers, and a four-way splitter network. The proposed AiP provides 42 dB of active gain at the boresight. The (EIRP) of the current module is 41 dBm at the 1-dB compression point of the active beamformer chips and it consumes 2.6 W of DC power when the system radiates left-handed circular polarization at the boresight. Calibration and radiation pattern measurement of the system is also discussed and the measurement results for a case of left-handed circularly polarized (LHCP) radiation is presented. In chapter III, a 4×4 bi-directional antenna array with integrated passive beamformer with left-handed circular polarization (LHCP) radiation is presented. Hybrid approach that combines active and passive PAA architectures is an alternative solution in lowering the cost and complexity of active PAA systems. The design and implementation aspects of a 4×4 antenna array with integrated passive beamformer for low-cost and efficient millimeter wave applications is presented. The phase shifter’s operational principle and actuation mechanism are discussed in detail. Slow-wave structure is employed to shrink the size of the phase shifter. The simulation and measurement results of the phase shifter are presented. Measurement results show the maximum insertion loss of 2.2 dB in all the tuning states and the insertion loss variation is 1.2 dB. Also, it provides 380º of the phase tuning range in a compact footprint area of 2.4 mm × 3 mm. 2D P-PAA is designed, simulated and measured over the operating band. Measurement results show the antenna‘s main beam can be steered over an angular range of ±30º in both elevation and azimuth planes.. The operating frequency bandwidth of the system ranges from 28-30 GHz. The antenna’s main characteristics, such as radiation pattern, directivity, efficiency, and reflection coefficient are measured and presented

    2020 NASA Technology Taxonomy

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    This document is an update (new photos used) of the PDF version of the 2020 NASA Technology Taxonomy that will be available to download on the OCT Public Website. The updated 2020 NASA Technology Taxonomy, or "technology dictionary", uses a technology discipline based approach that realigns like-technologies independent of their application within the NASA mission portfolio. This tool is meant to serve as a common technology discipline-based communication tool across the agency and with its partners in other government agencies, academia, industry, and across the world

    MEMS deformable mirror CubeSat testbed

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    To meet the high contrast requirement of 1 × 10[superscript −10] to image an Earth-like planet around a Sun-like star, space telescopes equipped with coronagraphs require wavefront control systems. Deformable mirrors are a key element of these systems that correct for optical imperfections, thermal distortions, and diffraction that would otherwise corrupt the wavefront and ruin the contrast. However, high-actuator-count MEMS deformable mirrors have yet to fly in space long enough to characterize their on-orbit performance and reduce risk by developing and operating their supporting systems. The goal of the MEMS Deformable Mirror CubeSat Testbed is to develop a CubeSat-scale demonstration of MEMS deformable mirror and wavefront sensing technology. In this paper, we consider two approaches for a MEMS deformable mirror technology demonstration payload that will fit within the mass, power, and volume constraints of a CubeSat: 1) a Michelson interferometer and 2) a Shack-Hartmann wavefront sensor. We clarify the constraints on the payload based on the resources required for supporting CubeSat subsystems drawn from subsystems that we have developed for a different CubeSat flight project. We discuss results from payload lab prototypes and their utility in defining mission requirements.United States. National Aeronautics and Space Administration (Office of the Chief Technologist NASA Space Technology Research Fellowship)Jeptha and Emily Wade FundMassachusetts Institute of Technology. Undergraduate Research Opportunities Progra

    Photonic controlled metasurface for intelligent antenna beam steering applications including 6G mobile communication systems

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    This paper presents a novel metasurface antenna whose radiation characteristics can be remotely controlled by optical means using PIN photodiodes. The proposed reconfigurable antenna is implemented using a single radiating element to minimize the size and complexity. The antenna is shown to exhibit a large impedance bandwidth and is capable of radiating energy in a specified direction. The proposed antenna consists of a standard rectangular patch on which is embedded an H-tree shaped fractal slot of order 3. The fractal slot is used to effectively reduce the physical size of the patch by 75 % and to enhance its impedance bandwidth. A metasurface layer is strategically placed above the patch radiator with a narrow air gap between the two. The metasurface layer is a lattice pattern of square framed rhombus ring shaped unit-cells that are interconnected by PIN photodiodes. The metasurface layer essentially acts like a superstrate when exposed to RF/microwave radiation. Placed below the patch antenna is a conductive layer that acts like a reflector to enhance the front-toback ratio by blocking radiation from the backside of the patch radiator. The patch’s main beam can be precisely controlled by photonically illuminating the metasurface layer. The antenna’s performance was modelled and analyzed with a commercial 3D electromagnetic solver. The antenna was fabricated on a standard dielectric substrate FR4 and has dimensions of 0.778λo × 0.778λo × 0.25λo mm3 , where λo is the wavelength of free space centered at 1.35 GHz. Measured results confirm the antenna’s performance. The antenna exhibits a wide fractional band of 55.5 % from 0.978 to 1.73 GHz for reflection-coefficient (S11) better than − 10 dB. It has a maximum gain of 9 dBi at 1.35 GHz with a maximum front-to-back ratio (F/B) of 21 dBi. The main beam can be steered in the elevation plane from − 24◦ to +24◦. The advantage of the proposed antenna is it does not require any mechanical movements or complicated electronic systems.Dr. Mohammad Alibakhshikenari acknowledges support from the CONEX-Plus programme funded by Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 801538. The authors also sincerely appreciate funding from Researchers Supporting Project number (RSP2023R58), King Saud University, Riyadh, Saudi Arabia. Additionally, this work was supported by Ministerio de Ciencia, Innovación y Universidades, Gobierno de España (Agencia Estatal de Investigación, Fondo Europeo de Desarrollo Regional -FEDER-, European Union) under the research grant PID2021-127409OB-C31 CONDOR. Besides above, the Article Processing Charge (APC) was afforded by Universidad Carlos III de Madrid (Read & Publish Agreement CRUE-CSIC 2023)

    Packages for Terahertz Electronics

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    In the last couple of decades, solid-state device technologies, particularly electronic semiconductor devices, have been greatly advanced and investigated for possible adoption in various terahertz (THz) applications, such as imaging, security, and wireless communications. In tandem with these investigations, researchers have been exploring ways to package those THz electronic devices and integrated circuits for practical use. Packages are fundamentally expected to provide a physical housing for devices and integrated circuits (ICs) and reliable signal interconnections from the inside to the outside or vice versa. However, as frequency increases, we face several challenges associated with signal loss, dimensions, and fabrication. This paper provides a broad overview of recent progress in interconnections and packaging technologies dealing with these issues for THz electronics. In particular, emerging concepts based on commercial ceramic technologies, micromachining, and 3-D printing technologies for compact and lightweight packaging in practical applications are highlighted, along with metallic split blocks with rectangular waveguides, which are still considered the most valid and reliable approach.119Ysciescopu
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