Rozprawy doktorskie: „Active phased array”

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Micheli, Victor A. "Active phased array radar analysis". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA318791.

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Thesis (M.S. in Systems Engineering) Naval Postgraduate School, September 1996.
Thesis advisor(s): Chin-Hwa Lee. "September 1996." Includes bibliographical references (p. 59-63). Also available online.

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da, Silva Neddef N. (Nedio). "Active phased array transceiver:an operational compensation for a multiple phase shifter system". Master's thesis, University of Oulu, 2018. http://jultika.oulu.fi/Record/nbnfioulu-201805151790.

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Abstract. The upcoming fifth-generation mobile technology relies on the implementation of beamforming techniques to fulfill the requirements proposed for the 2020 roll-out. One of the processes for stepping up this technique from the high-end applications to the telecommunication mass market is to be able to test, analyze and tune the product according to the specifications. After the manufacturing process, the phased antenna array, beamforming and beam-steering system must be tested against a prediction model, and corrected against deviations due to the uniqueness of the components, with the objective to conform the final product to be in accordance with specifications, while at low cost and time. The aim of this work is to propose and test different procedures for calibrating the phase component of an RF phased array transceiver with multiple phase-shifters. The different proposed procedures are compared in an over-the-air measurement through the performance when applying the beamforming and beam-steering techniques.

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Scattone, Francesco. "Phased array antenna with significant reduction of active controls". Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S168/document.

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L'objectif de cette thèse est d'exploiter les phénomènes des ondes de fuite pour améliorer les performances des antennes classiques à ouverture pour les applications spatiales. Ici, nous considérons des configurations planaires où les ondes de fuite sont excitées entre un plan de masse et un superstrat partiellement réfléchissant. Des réseaux de petites ouvertures sur le plan de masse sont utilisés pour alimenter les antennes considérées. Les structures avec superstrat sont développées en configuration réseaux simples ou réseaux à commande de phase, considérées intéressantes en termes de flexibilité du système pour des liens satellitaires de nouvelle génération.Pour étudier efficacement ces antennes, nous avons développé un outil d'analyse basé sur une approche spectrale avec fonction de Green. Cet outil permet d'analyser les structures proposées en prenant en compte l'impact du couplage mutuel entre les éléments sur les performances de rayonnement avec une réduction du temps de calcul et d'utilisation de mémoire.L'augmentation du gain des structures à ondes de fuite peut ouvrir la voie à la réduction du nombre d'éléments des réseaux associés, et donc des commandes en amplitude et phase. Dans une configuration à ondes de fuite, chaque élément du réseau rayonne avec une ouverture équivalente plus grande, augmentant ainsi l'espacement entre les éléments sans affecter le gain global de la structure. Comme largement expliqué dans le manuscrit, les solutions à ondes de fuite représentent par conséquent un avantage majeur pour les antennes du segment utilisateur.En plus de l'amélioration du gain, la technologie à ondes de fuite peut être efficacement exploitée pour synthétiser le diagramme de rayonnement, en choisissant correctement les paramètres de conception de l'antenne. Cette caractéristique peut être utilisée dans les réseaux à commande de phase, pour produire un diagramme d'élément qui minimise les pertes par dépointage et qui filtre les lobes de réseaux. Une procédure de synthèse pour des antennes réseaux raréfiés à ondes de fuite est ainsi présentée dans le manuscrit, ainsi qu'une nouvelle configuration de réseaux avec superstrat irrégulier. Ce dernier permet de réduire les lobes secondaires de l'antenne en utilisant une excitation uniforme. Cette dernière configuration montre clairement que la capacité de modifier le diagramme de rayonnement est la caractéristique la plus attrayante des antennes planaires à ondes de fuite, pour être utilisée dans des solutions de réseaux à commande de phase
The objective of this thesis is to exploit the leaky-wave phenomena to enhance the performance of classical aperture antennas for space applications. Here, we consider planar configurations where the leaky modes are excited between a ground plane and a partially reflective superstrate. Arrangements of small apertures opening on the ground plane are used to feed the antennas under study. The superstrate-like leaky-wave structures are developed in array or phased array configurations, considered of interest in terms of flexibility of the system for next generation satellite links. In order to efficiently study planar leaky-wave arrays, we have developed an analysis tool based on a Green's function spectral approach. The developed tool allows to precisely analyze the proposed structure by taking into account the impact of the mutual coupling among the elements on the radiation performance of the whole antenna. In addition, it can handle extremely large structures in terms of wavelengths with a small computational effort with respect to commercial tools. In particular, the gain enhancement of leaky-based structures can pave the way to the reduction of the number of elements of the associated phased arrays. In a leaky-wave configuration each element of the array will radiate with a larger equivalent aperture allowing a larger spacing among elements without affecting the final gain of the whole structure. This aspect is particularly important in the case of phased arrays, where phase shifters and control cells are, typically, the most expensive components of the system. As extensively explained in the manuscript, antennas for user segment might find the highest benefit by using leaky-wave solutions. Besides the gain enhancement, the leaky-wave technology can be effectively exploited to conveniently shape the radiation pattern by properly engineering the design parameters of the antenna. This capability can be used in phased arrays to generate a convenient element pattern to minimize the scan losses and filter the grating lobes appearing in the visible space when dealing with periodicities larger than a wavelength. Therefore, a synthesis procedure for thinned leaky-wave arrays is presented in the manuscript. Also, a novel array configuration, the irregular superstrate array, is presented. The irregular superstrate allows the reduction of the side lobes of the antenna below -20 dB in the considered 2.5 % band, using a uniform excitation. This last configuration clearly shows that the shaping capability of leaky-wave antennas is the most appealing feature to be used in phased array solutions

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Yang, Zhenchao. "High-Efficiency Passive and Active Phased Arrays and Array Feeds for Satellite Communications". BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5741.

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Satellite communication (Satcom) services are used worldwide for voice, data, and video links due to various appealing features. Parabolic reflector antennas are typically used to serve a cost effective scheme for commercial applications. However, mount degradation, roof sag, and orbital decay motivate the need for beam steering. Limited scan range beam steering opens a third option for electronic beam steering with lower cost than full aperture phased arrays and higher tracking speed and accuracy than mechanical-only steering.Multiple high efficiency passive patch array feeds were designed, fabricated, and measured, including a 2x2 MSA array, a stacked shorted annular patch antenna, and an SIW-fed hexagonal array feed based on PTFE material, achieving performance comparable to a horn feed. For multiband dual polarization applications, passive MSA feed solutions are also provided. Multiple MSA array feeds with high isolation were designed for dual band dual polarization applications. More functionality can be realized with multi-layer PCB techniques for complex communication scenarios.Limited scan range electronic beam-steering with a parabolic reflector fed by an active array feed which only needs gain control was demonstrated experimentally, leading to a low cost and effective solution for active beam scanning. A cost-effective flat-panel phased array with limited scan range electronic beam-steering was proposed by tiling high efficiency 4x4 passive subarrays and performing beam scanning at the tile level. The sidelobe issue was also investigated to comply with the pattern mask requirement set by FCC.To enable better use of circularly polarized (CP) MSAs for electronically beam-formed antenna systems, the impact of mutual coupling on the performance of high-sensitivity dual-polarized receivers for satellite communications applications was analyzed. A new analysis method for intrinsically dual-CP MSAs based on an equivalent circuit model and Jones matrices was proposed and validated to overcome the port isolation challenge. The model provides accurate estimates of impedances and S-parameters, as well as field parameters such as axial ratio. The feasible region for XPI and impedance mismatch factor is found for dual CP antennas. The circuit model enables multiple useful applications. Effective decoupling and matching schemes was proposed and demonstrated, leading to a high isolation, good match, and wide AR bandwidth dual CP MSA for satellite communications.

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Bertulli, Scott. "MATLAB-Based Dipole Array Simulator Tool For MIT Haystack Observatory". Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-050505-104840/.

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Carter, David E. "Active Impedance Matching and Sensitivity Optimized Phased Array Feed Design For Radio Astronomy". BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2681.

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One of the many challenges in radio astronomy is the ability to make accurate measurements quickly. In recent years engineers and astronomers have begun implementing phased array feeds (PAFs) as a way to negate the long observation times required by single antenna feeds. Unfortunately, large mutual coupling and other loss terms result in low sensitivity, restricting PAF usefulness in on dish observation. This thesis addresses several ways to reduce mutual coupling and maximize sensitivity for PAFs in radio astronomy. Antenna design of this magnitude requires accurate modeling capabilities. To this end, electromagnetic software models and low loss component designs are verified and validated with measured data. This process required the construction of a 50 Ω matched dipole and measurements on a network analyzer at Brigham Young University. The design and optimization of several single and dual polarization hexagonal grid arrays of 19 and 38 elements respectively are also described. Model figures of merit are compared with measurements taken on the 20-Meter dish at the National Radio Astronomy Observatory (NRAO) in Green Bank, WV and the 300 meter dish at the Arecibo Observatory in Arecibo, PR. Although some unexplained discrepancies exist between measured and model datasets, the dual pol cryocooled kite array described boasts the highest PAF sensitivity ever measured.

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Coen, Christopher T. "Development and integration of silicon-germanium front-end electronics for active phased-array antennas". Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48990.

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The research presented in this thesis leverages silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) technology to develop microwave front-end electronics for active phased-array antennas. The highly integrated electronics will reduce costs and improve the feasibility of snow measurements from airborne and space-borne platforms. Chapter 1 presents the motivation of this research, focusing on the technological needs of snow measurement missions. The fundamentals and benefits of SiGe HBTs and phased-array antennas for these missions are discussed as well. Chapter 2 discusses SiGe power amplifier design considerations for radar systems. Basic power amplifier design concepts, power limitations in SiGe HBTs, and techniques for increasing the output power of SiGe HBT PAs are reviewed. Chapter 3 presents the design and characterization of a robust medium power X-band SiGe power amplifier for integration into a SiGe transmit/receive module. The PA design process applies the concepts presented in Chapter 2. A detailed investigation into measurement-to-simulation discrepancies is outlined as well. Chapter 4 discusses the development and characterization of a single-chip X-band SiGe T/R module for integration into a very thin, lightweight active phased array antenna panel. The system-on-package antenna combines the high performance and integration potential of SiGe technologies with advanced substrates and packaging techniques to develop a high performance scalable antenna panel using relatively low-cost materials and silicon-based electronics. The antenna panel presented in this chapter will enable airborne SCLP measurements and advance the technology towards an eventual space-based SCLP measurement instrument that will satisfy a critical Earth science need. Finally, Chapter 5 provides concluding remarks and discusses future research directions.

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Gholami, Mehrdad. "A C-Band Compact High Power Active Integrated Phased Array Transmitter Module Using GaN Technology". Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36045.

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In this research, an innovative phased array antenna module is proposed to implement a high-power, high-efficient and compact C-band radio transmitter. The module configuration, which can be integrated into front-end circuits, was designed as planar layers stacked up together to form a metallic cube. The layers were fabricated by using a Computer Numerical Control (CNC) milling machine and screwed together. The antenna parts and the amplifier units were designed at two opposite sides of the cube to spread the dissipated heat produced by the amplifiers and act as a heat sink. Merging the antenna parts with the amplifier circuits offers additional advantages such as decreasing the total power loss, mass, and volume of the transmitter modules by removing the extra power divider and combiner networks and connectors between them as well as reducing the total signal path. To achieve both a maximum possible radiation efficiency and high directivity, the aperture waveguide antenna was selected as the array element. Four antenna elements have been located in a cavity to be excited equally and the cavity is excited through a slot on its underside so a compact subarray is formed. Antenna measurements demonstrated a 15.5 dBi gain and 20 dB return loss at 10 % fractional bandwidth centered around 5.8 GHz and with more than 98% radiation efficiency. The total dimensions of the subarray are approximately 8*12*4 cm3. The outcoming signal from the amplifiers is transferred into the slot exciting the subarray through a microstrip-to-waveguide transition (MWT). A novel and robust MWT structure was designed for the presented application. The MWT was also integrated with a microstrip coupler to monitor the power from the amplifier output. The measured insertion loss of the MWT along with the microstrip coupler was less than 0.25 dB along with more than 20 dB return loss within the same bandwidth of the subarray. The microstrip coupler shows 38 dB of coupling and more than 48 dB of isolation with negligible effects on the amplifier output signal and the insertion/return loss of the MWT. The amplifier subcomponents consist of power combiners/dividers (PCDs), high power amplifiers (HPAs) and bias circuitry. A Monolithic Microwave Integrated Circuit (MMIC) three-stage HPA was designed in a commercially available 0.15 um AlGaN/GaN HEMT technology provided by National Research Council Canada (NRC) and occupies an area of 4.7*3.7 mm2. To stabilize the HPA, a novel inductive degeneration technique was successfully used. To the best of the author’s knowledge, this is the first time this technique has been used to stabilize HPAs. Careful considerations on input/output impedances of all HEMTs were taken into account to prevent parametric oscillations. Other instability sources, i.e. odd-mode, even-mode, and low frequency (bias circuit) oscillations were also prevented by designing the required stabilization circuits. The electromagnetic simulation of the HPA shows 35 W (45.5 dBm) of saturated output power, 26 dB large signal gain and 29% power added efficiency within the same operating bandwidth as the subarray. The output distortion is less than 27 dB, indicating that the HPA is highly linear. The PCD was designed by utilizing a novel, enhanced configuration of a Gysel structure implemented on Rogers RT-Duroid5880. The insertion loss of the Gysel is less than 0.2 dB while return loss and isolation are greater than 20 dB over the entire bandwidth. The same subarray area (8*12 cm2) has been used for the amplifier circuits and up to eight HPAs can be included in each module. All the above parts of the transmitter module were fabricated and measured, except the MMIC-HPA.

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Webb, Taylor D. "Design and Polarimetric Calibration of Dual-Polarized Phased Array Feeds for Radio Astronomy". BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3321.

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Research institutions around the globe are developing phased array feed (PAF) systems for wide-field L-band radio astronomical observations. PAFs offer faster survey speeds and larger fields of view than standard single-pixel feeds, which enable rapid sky surveys and significantly increased scientific capability. Because deep space astronomical signals are inherently weak, PAF systems must meet stringent noise and sensitivity requirements. Meeting these requirements requires detailed modeling of the phased array itself as well as the reflector it is mounted on. This thesis details a novel approach to dual-pol PAF design that models the array and reflector as a complete system in order to achieve a more optimal sensitivity and system noise temperature. The design and construction of two arrays designed using this technique is discussed. The implementation of a data acquisition system to receive data from the first of these arrays is also detailed. Polarization state information plays an important role in understanding cosmological processes for many deep space sources. Because of phase and gain imbalances in the LNAs and receiver chains calibration is required for accurate measurement of polarization by phased array feeds. As a result accurate polarimetric calibration techniques are essential for many observations. Existing polarimetric calibration methods are based on assumptions about the form of the system Mueller matrix that limit the generality of the method or require long observations of a polarized source which is time-consuming for multiple PAF beams. This thesis introduces a more efficient method of calibration that uses only three snapshot observations of bright astronomical calibrator sources, one unpolarized and two partially polarized. The design of an engineering array for the Green Bank Telescope is discussed. Measured results from a prototype element are presented along with simulated on-reflector results for the full array. Simulations predict that the array will be the highest sensitivity dual pol feed built by the Radio Astronomy Systems group at Brigham Young University to date.

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Sy, Chérif Hamidou. "Etude des inductances actives intégrées en bande HF/UHF-L et leurs applications potentielles à la radioastronomie". Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2042/document.

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Ce travail de thèse entre dans le cadre de projets nationaux et internationaux de radioastronomie d'une manière générale et en particulier dans celui de SKA (Square Kilometre Array). La conception de circuits intégrés d’applications spécifiques devient de plus en plus importante dans ce domaine. La première étape de ce travail consiste à une étude bibliographique sur les inductances actives intégrées et leurs principales applications dédiées à la radioastronomie. Cette étude a permis de faire un état de l'art. Cet état de l'art a fait ressortir que l'intégration de certaines fonctions s'avère particulièrement difficile voire impossible dès lors que l'utilisation d'une inductance est nécessaire. Ceci est essentiellement dû à la taille importante des inductances. Parmi ces fonctions, nous avons le filtrage, certains types de transceivers, le temps de retard, etc. Or ces fonctions sont très importantes dans une architecture de radiofréquence propre aux réseaux d'antennes phasées. Ce travail de thèse est donc consacré à l'étude et la conception de ces différentes fonctions à l'aide des inductances actives basées sur des topologies à gyrateurs en technologie SiGeC 0,25 μm afin de palier aux problèmes d'intégration. Une des finalités de cette thèse est aussi de montrer que la consommation de ce procédé d'intégration n’est pas si excessive pour ces applications, par rapport à l’utilisation d’inductances localisées intégrées occupant une surface importante sur le substrat. Ce dernier point sera un résultat très important pour les projets où la très haute intégration à bas coût est nécessaire, point clé de réussite des réseaux phasés denses du projet international SKA
This thesis work is part of national and international projects of radio-astronomy in general and in particular that of the SKA (Square Kilometre Array). The design of integrated circuits for specific applications is becoming increasingly important in this field. The first step in this work is a bibliography study on integrated active reactors and their main applications dedicated to radio astronomy. This study allowed making a state of the art. This state of the art has highlighted that the integration of some functions is made especially difficult by the need to use an inductor. This is mainly due to the large size of passive inductors. These functions include the filtering function, some transceivers types, the time delay, etc. But, they are very important in radio-frequency architecture owing to phased array antennas. This thesis propose the study and design of these different functions using active inductors based on gyrators topologies in SiGeC 0.25 μm technology in order to overcome the integration problems. One of the aims of this thesis is to show that the consumption of this integration process is not so excessive for these applications, compared to the use of integrated located inductors occupying a large area on the substrate. This last point is a very important result for projects where high integration at low cost is necessary, key point of the success of dense phased array in the SKA international project

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Esswein, Lance C. "Genetic algorithm design and testing of a random element 3-D 2.4 GHZ phased array transmit antenna constructed of commercial RF microchips". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Jun%5FEsswein.pdf.

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Thesis (M.S. in Physics)--Naval Postgraduate School, June 2003.
Thesis advisor(s): Michael Melich, David Jenn, Rodney Johnson. Includes bibliographical references (p. 113-115). Also available online.

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Patterson, Chad E. "Exploration of liquid crystal polymer packaging techniques for rf wireless systems". Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44800.

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In the past decade, there has been an increased interest in low-cost, low-power, high data rate wireless systems for both commercial and defense applications. Some of these include air defense systems, remote sensing radars, and communication systems that are used for unmanned aerial vehicles, ground vehicles, and even the individual consumer. All of these applications require state-of-the-art technologies to push the limits on several design factors such as functionality, weight, size, conformity, and performance while remaining cost effective. There are several potential solutions to accomplish these objectives and a highly pursued path is through the utilization of advanced integrated system platforms with high frequency, versatile, multilayered materials. This work intends to explore advanced 3-D integration for state-of the art components in wireless systems using LCP multilayer organic platforms. Several packaging techniques are discussed that utilize the inherent benefits of this material. Wire bond, via interconnect, and flip-chip packages are implemented at RF and millimeter-wave (mm-wave) frequencies to explore the benefits of each in terms of convenience, reliability, cost, and performance. These techniques are then utilized for the demonstration of bulk acoustic waveguide (BAW) filter applications and for the realization of highly integrated phased-array antenna systems.

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Козачук, Оксана Дмитрівна, i Oksana D. Kozachuk. "Математичні моделі оцінки надійності радіоелектронних систем". Thesis, Національний авіаційний університет, 2021. https://er.nau.edu.ua/handle/NAU/48990.

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Робота присвячена розвитку математичних моделей оцінки надійності радіоелектронних систем (РС) з активними фазованими антенними решітками (АФАР). У роботі розроблений комплекс математичних моделей апроксимації кривих інтенсивностей відмов електрорадіовиробів імовірнісними розподілами, що описують раптові і поступові відмови. Досліджено вплив коефіцієнта надмірності РС з розподіленою структурою при різних імовірнісних розподілах відмов вузлів, каналів і модулів. Побудовані та досліджені моделі оцінки надійності РС з АФАР при раптових і поступових відмовах каналів і модулів. Аналіз впливу поступових відмов модулів антенних решіток під час оцінки надійності РС дозволяє підвищити оцінку середнього наробітку до відмови АФАР від 30% до 80%. Розроблено та досліджено математичну модель оцінки надійності АФАР РС в залежності від температури активної зони кристалів GaN (нітриду галію) мікромодулів, що дозволяє вибрати оптимальну структуру системи рідинного охолодження.
The work is devoted to the development of mathematical models for assessing the reliability of radio electronic systems (RS) with active phased antenna arrays (APAA). The work developed a complex of mathematical models for approximating the curves of failure rates of electrical radio products by probability distributions describing sudden and gradual failures. The influence of the redundancy factor of a distributed structure with different probabilistic distributions of failures of nodes, channels and modules is investigated. Models for assessing the reliability of RS with APAA in case of sudden and gradual failures of channels and modules have been built and investigated. Taking into account the effect of gradual failures of antenna array modules in assessing the reliability of the RS allows to increase the estimate of the average operating time before the APAA failure from 30 % to 80 %. A mathematical model has been developed and investigated for assessing the reliability of the APAA RS depending on the temperature of the core of GaN (gallium nitride) crystals of micro modules, which makes it possible to choose the optimal structure of the liquid cooling system.

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Kövamees, Johan. "Electrically Steerable Phased-Arrays for 5G Sub-6 GHzMassive MIMO Active Antenna Units : Re-configurable Feed Networks". Thesis, Uppsala universitet, Institutionen för elektroteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-420712.

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During this project we have designed a new type of antenna that uses an array of antenna elements in order to emit electromagnetic radiation as signals and to be able to control the beam. After an extended time the design yielded a simulation which had the correct characteristics. After printing and constructing a prototype of the antenna it was tested in an anechoic chamber at Uppsala University. The array was divided into two different sub-arrays: the upper and the lower sub-arrays. Each of these consisted in itself of two sides: the long and the short sides. Each side had seven radiating elements, during the tests only one of the two sub-arrays (upper or lower) was running. Both sub-arrays are excited via a rat-race or 90 degree coupler. While the antenna was running it had 14 radiating elements and two phase shifters, two per sub-array and two per side. The idea was for a signal to travel passing the radiating elements and the phase shifter which would steer the induced electromagnetic signal in one direction, a traveling-wave array. This direction could be changed since the phase shifters were configurable in three different states per phase shifter, hence the induced electromagnetic beam was steerable. The beam was also steerable through the feed which was re-configurable, since there were two feeds per sub-array a phase shift could be introduced between the long and the short side. The beam steering range was between -2 degrees and 11 degrees oriented as 0 degrees would be a perpendicular line from the array to the receiving end. The design itself worked which could be stated from the results in the upper part of the array, the test results from the lower part however did not match the simulated results. This is likely due to an error in the construction of the antenna rather than the theory since the upper and lower part of the array was mirrored versions of each other. The phase shifters worked as intended in the bigger picture but were slightly different in the simulations compared to the physical ones, likely due to the same type of error source as regarding the full antenna.

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Ingram, David. "An Evaluation of Harmonic Isolation Techniques for Three Phase Active Filtering". Thesis, University of Canterbury. Electrical and Computer Engineering, 1998. http://hdl.handle.net/10092/1260.

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Recent advances in power electronics have lead to the wide spread adoption of advanced power supplies and energy efficient devices. This has lead to increased levels of harmonic currents in power systems, degrading the performance of electrical machinery and interfering with telecommunication services. Active filters provide a solution to these problems by compensating for the distorted currents drawn by non-linear loads. Optimal methods for controlling these active filters have been determined by computer simulation and experimental implementation. Methods used for isolating the harmonic content of an unbalanced three phase load current were compared by computer simulations. A technique based on the Fast Fourier Transform (FFT) was developed as part of this work and shown to perform favourably. Notch Filtering, Sinusoidal Subtraction, Instantaneous Reactive Power Theory, Synchronous Reference Frame and Fast Fourier Transform methods were simulated. The methods shown to be suitable for compensation of three phase unbalanced loads were implemented in a Digital Signal Processor to evaluate true performance. These methods were Notch Filtering, Sinusoidal Subtraction, Fast Fourier Transform, and a High Pass Filter based method. A completely digital hysteresis current controller for a three phase active filter inverter has been developed and implemented with a Field Programmable Gate Array. This controller interfaces directly to a digital signal processor and is resistant to electromagnetic interference. Results from the experimental hardware verified that the active filter model used for simulation is accurate, and may be used for further development of harmonic isolation methods. A technique using notch filtering gives the best performance for steady loads, with the FFT based technique giving the most flexible operation for a range of load current characteristics. Novel use of the FFT based harmonic isolation technique allows selective cancellation of individual harmonics, with particular application to multiple shunt filters connected in parallel.

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Vickerstaffe, Emma. "The development and application of automated multi-step polymer assisted solution phase synthesis for the production of biologically active compound arrays". Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614773.

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Capelli, Thomas. "Amplificateur de puissance pour réseaux phasés d’antenne 5G multi-bande en technologie ST CMOS065SOIMMW". Thesis, Bordeaux, 2022. http://www.theses.fr/2022BORD0176.

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Les télécommunications mobiles, afin de subvenir à leurs insatiables besoins, trouvent des moyens d’améliorer leurs capacités depuis maintenant plus de trente ans. En 2019 la cinquième génération (5G) est à l’épreuve afin de garantir une connexion non seulement au marché des téléphones mobiles toujours croissant, mais aussi au vaste univers de l’internet des objets (IoT). Afin de pouvoir remplir ses objectifs, la 5G marque une expansion sans précédent en matière de bandes de fréquences utilisées. En effet, des bandes jusqu’à 60 GHz et plus font partie des ambitions du réseau et cela implique de radicaux changements technologiques qui impactent toute l’électronique dédiée. Nouvelles fréquences plus élevées, pertes de propagation dans l’air plus élevées et niveau d’exigences relevé, les réseaux phasés d’antenne sont introduits pour pallier à toutes ces contraintes et imposent une toute nouvelle architecture système et une interface inédite pour les front-end RF des communications mobiles.Dans ce travail, nous proposons donc une analyse de ces réseaux d’antennes phasés et des contraintes qu’ils représentent en particulier pour les amplificateurs de puissance (PA), tel que la variation de charge parasite et le comportement des composantes générées par le comportement non-linéraire de ces derniers. Une évaluation de la variation de charge active due aux différents couplages existants dans les réseaux d’antennes est proposée ainsi que de son impact sur la performance des amplificateurs notamment en termes d’efficacité (PAE). Le comportement des non-linéarités telles que les produits d’intermodulation du troisième ordre (IMD3) est montré dans les réseaux d’antennes. Un concept utilisant le principe de génération et d’orientation de faisceau des réseaux d’antennes est proposé, permettant de relâcher les contraintes de linéarité des amplificateurs 5G et ainsi de permettre une réduction de leur consommation d’énergie. Une implémentation d’un PA utilisant ce principe est démontrée en technologie ST CMOS 65 nm PD-SOI à 28 GHz
Mobile telecommunications, in order to support its insatiable needs, has been finding ways to improve its capabilities for over thirty years now. In 2019 the fifth generation (5G) is on trial to ensure connection not only to the ever-growing cell phone market, but also to the vast world of the Internet of Things (IoT). In order to meet its goals, 5G marks an unprecedented expansion in the frequency bands used. Indeed, bands up to 60 GHz and beyond are part of the network's ambitions and this implies radical technological changes that impact all dedicated electronics. New higher frequencies, higher propagation losses in the air, and higher requirements, antenna phased arrays are introduced to overcome all these constraints and impose a completely new system architecture and interface for the RF front-end of mobile communications.In this work, we propose an analysis of these phased antenna arrays and the constraints they represent particularly for power amplifiers (PA), such as the parasitic load variation and the behavior of the components generated by the non-linear behavior of the latter. An evaluation of the active load variation due to the different coupling existing in the antenna networks is proposed as well as its impact on the performance of the amplifiers, particularly in terms of power added efficiency (PAE). The behavior of nonlinearities such as third-order intermodulation products (IMD3) is shown in antenna arrays. A concept using the principle of beam generation and steering of antenna arrays is proposed, allowing for relaxing the linearity constraints of 5G amplifiers and thus allowing a reduction of their power consumption. An implementation of an AP using this principle is demonstrated in ST CMOS 65 nm PD-SOI technology at 28 GHz

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18

Ahsan, Naveed. "Programmable and Tunable Circuits for Flexible RF Front Ends". Licentiate thesis, Linköping University, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-14864.

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Most of today’s microwave circuits are designed for specific function and specialneed. There is a growing trend to have flexible and reconfigurable circuits. Circuitsthat can be digitally programmed to achieve various functions based on specific needs. Realization of high frequency circuit blocks that can be dynamically reconfigured toachieve the desired performance seems to be challenging. However, with recentadvances in many areas of technology these demands can now be met.

Two concepts have been investigated in this thesis. The initial part presents thefeasibility of a flexible and programmable circuit (PROMFA) that can be utilized formultifunctional systems operating at microwave frequencies. Design details andPROMFA implementation is presented. This concept is based on an array of genericcells, which consists of a matrix of analog building blocks that can be dynamicallyreconfigured. Either each matrix element can be programmed independently or severalelements can be programmed collectively to achieve a specific function. The PROMFA circuit can therefore realize more complex functions, such as filters oroscillators. Realization of a flexible RF circuit based on generic cells is a new concept.In order to validate the idea, a test chip has been fabricated in a 0.2μm GaAs process, ED02AH from OMMIC^TM. Simulated and measured results are presented along withsome key applications like implementation of a widely tunable band pass filter and anactive corporate feed network.

The later part of the thesis covers the design and implementation of tunable andwideband highly linear LNAs that can be very useful for multistandard terminals suchas software defined radio (SDR). One of the key components in the design of a flexibleradio is low noise amplifier (LNA). Considering a multimode and multiband radiofront end, the LNA must provide adequate performance within a large frequency band.Optimization of LNA performance for a single frequency band is not suitable for thisapplication. There are two possible solutions for multiband and multimode radio frontends (a) Narrowband tunable LNAs (b) Wideband highly linear LNAs. A dual bandtunable LNA MMIC has been fabricated in 0.2μm GaAs process. A self tuningtechnique has also been proposed for the optimization of this LNA. This thesis alsopresents the design of a novel highly linear current mode LNA that can be used forwideband RF front ends for multistandard applications. Technology process for thiscircuit is 90nm CMOS.

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19

Chen, Yuan-Pu, i 陳元璞. "Active Phased Array Radar with Baseband Phase Shifting". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/43532a.

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碩士
國立交通大學
電子研究所
105
In convention, the military radar is mechanical, it receives the signal by rotating the antenna. The motion costs long time. Since the speed of detecting is very important in military, the method is left gradually. Electronic radar is presented, the phased array is the popular one. It receives signal at unique direction with some gain by circuits. Without rotating, it is faster than the conventional radar. This paper will introduce a 35 GHz 65nm CMOS scalable four-element phased array. The phased array receiver utilizes a homodyne topology and locate the phase shifter in baseband and the DC bias of while system is generated by a low supply voltage bandgap reference. The system also uses direct-coupled standing wave oscillator array to simplify the LO routing. Each receiver presents 66 dB conversion gain, 4.4 dB noise figure and each transmitter outputs sustainable 18.5dBm output power at 35GHz.

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20

Ke, Cheng-Yung, i 柯承詠. "Active Phased Array Radar with IF Phase Shifters". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/z8yy35.

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碩士
國立交通大學
電子研究所
107
This paper introduces an active phased array radar with the basic architecture and measurement analysis. This radar is based on 35 GHz scalable four-element phased array ICs in 65-nm CMOS. The phased array utilizes a homodyne topology and implements the phase shifter in IF. The DC bias of whole system is generated by a low supply voltage bandgap reference. The system uses direct-coupled standing wave oscillator array to simplify the LO routing. Each receiver has 66 dB conversion gain and 4.4 dB noise figure. And each transmitter output can reach 18.5 dBm output power at 35GHz. The radar uses embedded Vivaldi antennas to receive and transmit RF signal. A 1.09-GHz and a 50-MHz clock trees synchronize the analog and digital signals of all array elements respectively. To enhance phase stability, this paper introduces the concepts of thermal controller and thermal-feedback loop which stabilize temperature to a specific value. The IF phase shifter testkey IC solves some existing bugs and might simplify the calibration flow of phased array chips in the future.

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21

Kumar, Avnish. "Beamforming and Target Tracking Methods for Active RF Phased Array Seekers". Thesis, 2023. https://etd.iisc.ac.in/handle/2005/6174.

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The end game guidance and control of an interceptor for neutralization of a hypersonic vehicle or a maneuvering aerial target is a challenging problem. This problem can be addressed in two ways: through faster autopilot coupled with faster lateral error correction and through the use of better on-board homing sensor. The former demands not only sophisticated control and guidance algorithms, but also faster control mechanisms such as larger control surfaces driven through faster and bigger actuators, bulky reaction control systems or thrust vector control systems. All these options lead to increase in the weight of the system, which is not only undesirable with respect to weight penalty, but also makes the vehicle performance sluggish. The latter method helps to increase the homing duration via advances in sensor technology, which will lead to less dependence on heavier control systems. This transforms to a need of a seeker with larger lock-on and tracking range in order to cater to higher closing velocities. Active Radio Frequency Seekers are generally used as the homing sensor in long range interceptors, as they give all-weather applicability. For intercepting long range hypersonic targets, or highly manuvering aerial targets at longer ranges, Phased Array Seekers (PAS) are the promising homing sensor, as they give longer tracking ranges, even against targets with lower Radar Cross Section (RCS). Target tracking, and Line-Of-Sight (LOS) estimation through the PAS have poor efficacies, mainly due to the beam quantization, arising because of the phase angle digitization, resulting due to the use of Digital Phase Shifters (DPS). The limited space, as well as the constraint of weight, put a serious limit on the antenna aperture and the transmit power of the seeker. To achieve longer tracking ranges and better target parameter estimation, the seeker beam is required to position its boresight near to the target true LOS. This demands the placement of PAS beams in close vicinities, which is in contrast to the PAS capability, as the use of DPS limits the close placement of beams. A few papers in the existing literature propose the placement of beams in close vicinities through the use of truncated phase angles on to the PAS elements, incurring beam pointing errors. The pointing errors are proposed to be compensated through in-lab measurements and calibrations. This thesis proposes methods of high fidelity beamforming to reduce such calibration needs. We propose novel methods for reducing the beam pointing quantization in PAS, and derive their complete mathematical model. We also propose suitable strategies for effective target tracking through the PAS, which uses the proposed beamforming methods. In the first part of the thesis, we introduce novel methods for high fidelity beamforming with reduced beam quantization. In the first set of methods, named as Phase Angle Bunching (PAB) methods, we propose bunching of DPS digitized phase angles to be assigned to PAS elements. These methods are able to achieve error-free closely spaced beam pointing. Another set of methods, named as Phase Angle Round-Off (PARO) methods, has been proposed for the purpose, which gives lower beam pointing steps by using rounding-off of phase angles. An Optimal Rounding-Off realization has been derived to minimize beam pointing errors. Another novel method, named as Composite Beamforming (CB) method, has been proposed for partially reducing the step size by forming additional beams in-between the ideal feasible beams. The mathematical formulations for the beamforming, and the monopulse characterization for the CB method have also been derived. An Off-Axis scan philosophy over the composite beams has been proposed for the Line-Of-Sight (LOS) estimation, and the electronic beam steering. The CB method gives mathematically tractable partially reduced quantized beams, which makes the implementation of Off-Axis scan based on the mathematical model feasible, relaxing the need of extensive in-lab calibrations of the physical seeker. We have employed the proposed methods on Uniform Linear Arrays (ULA) to demonstrate their efficacies. We propose unique strategies, to assign the relative phase angles to the ULA elements, for each of the proposed methods and their realizations. The implementation aspects and approaches for the proposed methods, and when they are to be used for implementation on to the seeker, have also been discussed in the thesis. In the second part, we explore options for beam scanning and target tracking. First, the On-Axis scan method, which is in-general used in the on-board seeker, has been briefly discussed. Then, we have formalized an Off-Axis scan method based on the monopulse error characteristics of the PAS beams. We propose to use the Off-Axis scan, with the CB method, for the efficient tracking of target through the on-board PAS. The parametrization and characterization of the composite beams, for target Direction-Of-Arrival (DOA) estimation, have been carried out in the thesis. We have proposed strategies, to be used for the Off-Axis scan, to suppress the estimation noise dependent jitters, and to activate LOS dynamics depended beam switchings. In addition, to demonstrate the target tracking efficacies, we have carried out the implementation of the proposed Composite Off-Axis scan philosophy, to engage the target during the homing phase. The Proportional Navigation (PN) guidance scheme has been used for the engagement. We have carried out extensive Monte-Carlo simulations, to demonstrate and compare the performances of the four proposed target tracking strategies, for target tracking during the homing phase and interception. To summarize, the thesis contributes by developing high fidelity beamforming methods for forming closely spaced beams for active RF phased array seekers, and also proposes strategies for beam selection and beam switching during the target tracking.

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22

Gao, Jing-Zhi, i 高靖智. "Active Phased Array Receiver and Low-Supply-Voltage Bandgap Reference". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/y942dm.

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23

Mandeville, Andrew R. "An Orthogonally-Fed, Active Linear Phased Array of Tapered Slot Antennas". 2008. https://scholarworks.umass.edu/theses/114.

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An active, broadband antenna module amenable for use in low cost phased arrays is proposed. The module consists of a Vivaldi antenna integrated with a frequency conversion integrated circuit. A method of orthogonally mounting endfire antennas onto an array motherboard is developed using castellated vias. A castellated active isolated Vivaldi antenna package is designed, fabricated, and measured. An 8x1 phased array of castellated, active Vivaldi antenna packages is designed and assembled. Each element has approximately one octave of bandwidth centered in X-band, and each is mounted onto a coplanar waveguide motherboard. Radiation patterns of the array are measured at several frequencies and scan angles.

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24

Li, Chien-Te, i 李建德. "Digital Active Phased Array Radar and Radar Waveform Digital Signal Processing". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/7nbqnc.

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碩士
國立交通大學
電子研究所
107
Conventional radars are mechanically rotated to achieve signal reception in all directions. Therefore, the scanning speed is limited by the rotation of the antenna, and it is easy to wear and broken. It evolves into an electronic scanning radar, among them, a phase-controlled radar is the most. In the past, passive phase-controlled radar its phase shifter and the waveguide component will make signal correction difficult and the emission energy will be easily depleted. Therefore, the current radar trend has gradually turned into a digital active phase array radar, which controls each array unit to load the radar waveform while the digital signal is adjusted the phase. Through the Base-band enables the RF-band to synthesize the beam in the specified direction, achieving fast radar scanning and accurate correction, and implement a variety of radar applications by defining the waveform and timing control in all digital domain. This paper will introduce the full digital active phase array radar system, which implements phase control and timing control functions based on Field Programmable Gate Array (FPGA). It includes two radar waveform applications and its digital signal processing, such as frequency modulated continuous wave radar (FMCW), and linear frequency modulated (LFM) pulse-mode radar.

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25

Biglarbegian, Behzad. "Integrated Antennas and Active Beamformers Technology for mm-Wave Phased-Array Systems". Thesis, 2012. http://hdl.handle.net/10012/6632.

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In this thesis, based on the indoor channel measurements and ray-tracing modeling for the indoor mm-wave wireless communications, the challenges of the design of the radio in this band is studied. Considering the recently developed standards such as IEEE 802.15.3c, ECMA and WiGig at 60 GHz, the link budget of the system design for different classes of operation is done and the requirement for the antenna and other RF sections are extracted. Based on radiation characteristics of mm-wave and the fundamental limits of low-cost Silicon technology, it is shown that phased-array is the ultimate solution for the radio and physical layer of the mobile millimeter wave multi-Gb/s wireless networks. Different phased-array configurations are studied and a low-cost single-receiver array architecture with RF phase-shifting is proposed. A systematic approach to the analysis of the overall noise-figure of the proposed architecture is presented and the component technical requirements are derived for the system level specifications. The proposed on-chip antennas and antenna-in-packages for various applications are designed and verified by the measurement results. The design of patch antennas on the low-cost RT/Duroid substrate and the slot antennas on the IPD technologies as well as the compact on-chip slot DRA antenna are explained in the antenna design section. The design of reflective-type phase shifters in CMOS and MEMS technologies is explained. Finally, the design details of two developed 60 GHz integrated phased-arrays in CMOS technology are discussed. Front-end circuit blocks such as LNA, continuous passive reflective-type phase shifters, power combiner and variable gain amplifiers are investigated, designed and developed for a 60 GHz phased-array radio in CMOS technology. In the first design, the two-element CMOS phased-array front-ends based on passive phase shifting architecture is proposed and developed. In the second phased-array, the recently developed on-chip dielectric resonator antenna in our group in lower frequency is scaled and integrated with the front-end.

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26

"A low-cost active RFID indoor locationing system using phased array technology". 2012. http://library.cuhk.edu.hk/record=b5549027.

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近十年來，無線通訊技術、流動電話服務以及無線網絡的發展一日千里。不單止為社會帶來很多新的技術及先進的設備，更加帶來了許多新穎的應用構想。其中最被廣泛討論的要數室內無線實時定位系統。室內定位，顧名思義就是一種對一個或多個室內目標進行定位及追蹤的技術。這種技術的潛在應用非常多元化，例如倉庫管理、人力資源調配等等。透過這種技術可以使一些室內位置信息相關的服務更加自動化，從而提升服務效率。正因為市場狂熱的需求，近年來室內無線實時定位系統一直都是一個熱門的研究課題。
本論文的上半部主要是討論一種基於無線射頻識別技術的室內無線實時定位系統。這個系統的特點是在閱讀器的天線上應用了模擬一維綫相控陣列天線。系統的定位原理是基於三角測距法，透過相控陣的主波束掃描配合信號強度測量去估算出信號入射角。比較其他入射角測量的方法，應用這種方法的硬件成本更低而且能確保一定的精度。整個系統的開發包括有無線射頻標籤、閱讀器、模擬一維綫相控陣列天線、網絡控制器、數據庫、圖像應用界面及一種有效壓抑室內多徑問題的定位算法。這個系統的最大好處就是它不像其他一些現存的定位系統一樣，在安裝後需要進行大量的離線實地校準。我們進行了大量的實驗去客觀地驗證系統的定位性能，實驗的結果指出系統的定位誤差平均值小於一米。
為了控制系統的硬件成本，上述所提及到的模擬一維綫相控陣列天線會採用一種非常便宜的板材：FR4。但是FR4這種板材便宜的代價便是它相對較高的介質損耗。較高的介質損耗對模擬一維綫相控陣列天線的實現存在着一個重要的難題：模擬360º移相器的插入損耗相對電壓變化不平滑。有見及止，本論文的下半部會討論一種新穎而有效壓抑因高介質損耗而導致插入損耗不平滑的反射式移相器。新的移相器設計包含兩種壓抑插入損耗不平滑的技術。在仿真結果中，新的設計把傳統設計的插入損耗不平滑從1.4分貝大幅降低至0.3分貝。實驗的結果指出，在360o 的移相範圍內只存在着0.6分貝的插入損耗不平滑。
最後在此作一個總結。本論文主要是討論一種高效、低成本、基於無線射頻識別技術及模擬一維綫相控陣列天線技術的室內無線實時定位系統。大量的實驗數據證明了它良好的定位性能。而且系統的網絡設計使到它可以更彈性地應用到不同的場所。
In recent years, the rapid development in wireless communication technologies, mobile computing devices and wireless networks has stimulated a fast growing interest in various location-aware systems that can provide real time information of physical locations of objects or persons. In this thesis, an active radio frequency identification (RFID) indoor positioning system utilizing analog linear phased array antenna (PAA) technology has been proposed and demonstrated. By using beam steering of an analog linear PAA and measuring the corresponding received signal strength indicator (RSSI), one can determine the angle of arrival (AoA) of the transmitted signal from a tag. In this work, a complete locationing system has been built, which includes RFID tag, reader integrated PAA, network controller and database with event driven functions. Besides that, a novel positioning algorithm that can effectively overcome indoor multipath effect is also proposed. The major advantage of the proposed system is that it doesn’t require any on-site calibration. Therefore, the setup of the proposed system is scenario-independent. A large number of experiments and results have demonstrated that the probabilities of spatial errors of less than 1 meter and 1.5 meters of the proposed system are about 80% and 95% respectively.
In order to have a cost-effective system, those analog linear PAAs are fabricated in FR4 substrate, with which constant insertion loss under phase steering of a 360º analog phase shifter is difficult to realize due to the substrate loss. In order to overcome this difficulty, a novel loss-compensated microstrip 360º reflection-type diode phase shifter with constant insertion loss has been proposed and concept proven. In this regard, two techniques have been investigated to reduce the insertion loss variation which is caused by using lossy substrate. As compared with the conventional design, simulation results have shown a considerable improvement on the insertion loss variation from 1.4dB to 0.3dB. Measurement results have demonstrated a 0.6dB insertion loss variation over 360º phase steering range.
In conclusion, a low-cost but with moderate performance RFID indoor locationing system based on analog linear PAA technology has been proposed and experimentally demonstrated. The prototype system has shown its high accuracy, flexibility in network deployment, and scenario-independent operation.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Hung, Wing Hung.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2012.
Includes bibliographical references (leaves 85-87).
Abstracts also in Chinese.
ABSTRACT --- p.I
論文摘要 --- p.III
ACKNOWLEDGEMENT --- p.V
TABLE OF CONTENT --- p.VI
LIST OF FIGURES --- p.IX
LIST OF TABLES --- p.XIII
LIST OF ABBREVIATIONS --- p.XIV
Chapter CHAPTER 1 --- INTRODUCTION --- p.1
Chapter 1.1. --- RESEARCH MOTIVATION --- p.1
Chapter 1.2. --- OVERVIEW OF THE THESIS ORGANIZATION --- p.5
Chapter CHAPTER 2 --- FUNDAMENTALS IN LINEAR PHASED ARRAY ANTENNA AND REFLECTION-TYPE PHASE SHIFTER --- p.6
Chapter 2.1. --- LINEAR PHASED ARRAY ANTENNA --- p.6
Chapter 2.1.1. --- Operating Principle --- p.7
Chapter 2.1.2. --- Simulation Example --- p.9
Chapter 2.2. --- REFLECTION-TYPE PHASE SHIFTER --- p.10
Chapter 2.2.1. --- Operating Principle --- p.10
Chapter 2.2.2. --- Simulation Example --- p.12
Chapter CHAPTER 3 --- CONVENTIONAL INDOOR POSITIONING METHODOLOGIES --- p.15
Chapter 3.1. --- RSSI RANGING --- p.15
Chapter 3.1.1. --- Radio Fingerprint --- p.15
Chapter 3.1.2. --- Radio Propagation Model --- p.17
Chapter 3.1.3. --- Reference Tags --- p.18
Chapter 3.1.4. --- Ordered Signal Strength Sequence --- p.19
Chapter 3.2. --- UWB RANGING --- p.20
Chapter 3.3. --- NEAR FIELD ELECTROMAGNETIC RANGING (NFER) --- p.21
Chapter CHAPTER 4 --- CONVENTIONAL 360º REFLECTION-TYPE PHASE SHIFTER DESIGNS --- p.23
Chapter 4.1. --- PARALLELING TWO SERIES-RESONANT VARACTOR CIRCUIT --- p.23
Chapter 4.1.1. --- 360º Phase Shift --- p.24
Chapter 4.1.2. --- Constant Insertion Loss --- p.24
Chapter 4.1.3. --- Performance --- p.25
Chapter 4.2. --- PARALLELING TWO ARMS HAVING 180O PHASE CHANGE WITH 90º OUT OF PHASE --- p.27
Chapter 4.2.1. --- Linearity and 180º Phase Shift --- p.27
Chapter 4.2.2. --- Constant Insertion Loss --- p.29
Chapter 4.2.3. --- 360º Phase Shift --- p.29
Chapter 4.2.4. --- Performance --- p.30
Chapter 4.3. --- CONNECTING TWO ARMS HAVING 180O PHASE CHANGE WITH 90O OUT OF PHASE IN-SERIES --- p.31
Chapter 4.3.1. --- Constant Insertion Loss --- p.31
Chapter 4.3.2. --- 360º Phase Shift --- p.32
Chapter 4.3.3. --- Performance --- p.32
Chapter CHAPTER 5 --- AN ACTIVE RFID INDOOR POSITIONING SYSTEM UTILIZING ANALOG LINEAR PHASED ARRAY --- p.34
Chapter 5.1. --- POSITIONING METHODOLOGY --- p.35
Chapter 5.2. --- SYSTEM ARCHITECTURE --- p.37
Chapter 5.2.1. --- Analog Linear Phased Array Antenna --- p.39
Chapter 5.3. --- POSITIONING ALGORITHM --- p.51
Chapter 5.3.1. --- Zone Decision --- p.51
Chapter 5.3.2. --- Point Location --- p.52
Chapter 5.4. --- EXPERIMENTAL RESULT --- p.58
Chapter CHAPTER 6 --- NOVEL 360º REFLECTION-TYPE DIODE PHASE SHIFTER WITH CONSTANT INSERTION LOSS UNDER LOSSY SUBSTRATE --- p.65
Chapter 6.1. --- REVIEW --- p.66
Chapter 6.2. --- PROBLEMS --- p.68
Chapter 6.3. --- PROPOSED SOLUTIONS --- p.71
Chapter 6.3.1. --- Closed Reflection Coefficient Circle --- p.71
Chapter 6.3.2. --- Centered Reflection Coefficient Circle --- p.74
Chapter 6.4. --- SIMULATION AND MEASUREMENT RESULT --- p.77
Chapter CHAPTER 7 --- CONCLUSION --- p.83
REFERENCES --- p.85
AUTHOR’S PUBLICATIONS --- p.88
Chapter APPENDIX 1: --- DESIGN OF RFID TAG --- p.89
Chapter APPENDIX 2: --- DESIGN OF RFID READER --- p.98
Chapter APPENDIX 3: --- DESIGN OF RFID CONTROLLER --- p.100

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27

Lee, Kun-hua, i 李昆樺. "A Study on RFID Near-Field Reader Antenna and Active Phased Array". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/85288011596604935485.

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碩士
國立臺灣科技大學
電機工程系
96
This thesis proposes two near field reader antennas for applications in the UHF radio frequency identification (RFID) system. Strong vertical and horizontal magnetic fields in near zones are respectively induced by those two reader antennas, so that the readable distance of the near-field tags attached on objects can be enhanced significantly. Thus, the reader antennas are capable of near-field identification and positioning applications, such as the Point of Sale (POS) and intelligent bookshelf systems. For the POS system, the tags at any directions within certain range can be recognized by using the near-field reader antenna so that the manpower may be saved with better payment efficiency. As for the intelligent bookshelf system, it shows that a good identification ability with data searching and positioning of books can be immediately obtained through a middleware, so that the management efficiency and allocation of books may both be improved. On the other hand, a 3-bit phase shifter based on a vector sum method is presented to operate in the 2.4GHz ISM band, where some passive components including 180°directional coupler, 90°directional coupler and Wilkinson power divider are designed by using the artificial transmission line (ATL) to achieve both circuit miniaturization and good characteristics. A variable gain amplifier with a two-stage cascade structure is also designed to perform the gain variation, where the voltage of bias circuit is varied to meet the requirements of the output gain. An active phase shifter is obtained by combining the above passive and active RF components. Good performance in phase control is demonstrated with experimental results, which uses the voltage control of bias circuit to produce the different phase delays with nearly identical output gain. Further, the active phase shifter is applied to construct an active beam-forming network to design the phased array in this thesis. Therefore, the capability with electronic beam scanning of phased array is obtained and verified with measurements. Thus, the transmitting gain of the desired direction can be increased and the unwanted interferences from other directions may be suppressed. The active beam-forming network can be applied for positioning objects and improving coverage in the RFID system.

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28

Jiang, Yongqiang. "Photonic crystal waveguides based active and passive devices for phased array antenna systems". Thesis, 2006. http://hdl.handle.net/2152/2548.

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Venkatesh, Vijay. "Spaced-antenna wind estimation using an X-band active phased-array weather radar". 2013. https://scholarworks.umass.edu/dissertations/AAI3589208.

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Over the past few decades, several single radar methods have been developed to probe the kinematic structure of storms. All these methods trade angular-resolution to retrieve the wind-field. To date, the spaced-antenna method has been employed for profiling the ionosphere and the precipitation free lower atmosphere. This work focuses on applying the spaced-antenna method on an X-band active phased-array radar for high resolution horizontal wind-field retrieval from precipitation echoes. The ability to segment the array face into multiple displaced apertures allows for flexible spaced-antenna implementations. The methodology employed herein comprises of Monte-Carlo simulations to optimize the spaced-antenna system design and analysis of real data collected with the designed phased-array system. The contribution that underpins this dissertation is the demonstration of qualitative agreement between spaced-antenna and Doppler beam swinging retrievals based on real data. First, simulations of backscattered electric fields at the antenna array elements are validated using theoretical expressions. Based on the simulations, the degrees of freedom in the spaced-antenna system design are optimized for retrieval of mean baseline wind. We show that the designed X-band spaced-antenna system has lower retrieval uncertainty than the existing S-band spaced-antenna implementation on the NWRT. This is because of the flexibility to synthesize small overlapping apertures and the ability to obtain statistically independent samples at a faster rate at X-band. We then demonstrate a technique to make relative phase-center displacement measurements based on simulations and real data from the phased-array spaced-antenna system. This simple method uses statistics of precipitation echoes and apriori beamwidth measurements to make field repeatable phase-center displacement measurements. Finally, we test the hypothesis that wind-field curvature effects are common to both the spaced-antenna and Doppler beam swinging methods. Based on a close-range winter storm data set, we find that the spaced-antenna and fine-resolution Doppler beam swinging retrievals are in qualitative agreement. The correlation between the spaced-antenna and fine-resolution Doppler beam swinging retrievals was 0.57. The lowered correlation coefficient was, in part, due to the high standard deviation of the DBS retrievals. At high wind-speeds, the spaced-antenna retrievals significantly departed from variational retrievals of mean baseline wind.

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30

Su, Wei-Chih, i 蘇瑋智. "Study of Active Phased Array Using High Efficiency Class-E Injection-Locked Oscillators". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/95443511360843825709.

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碩士
國立中山大學
電機工程學系研究所
104
Since the processing of the baseband signal of 4G wireless communication has reached its limit, the solution to improve the data rate of 5G wireless communication system does not lie in the baseband signal processing. Because of that, this thesis studies a class-E injection-locked oscillator (ILO) array for use in a beam-forming system that can enhance the transmission speed. 　　Firstly, this paper designs a Class-E power amplifier (PA) as a basis of the injection-locked voltage controlled oscillator. Secondly, the feedback loop and injection port are added to the class-E PA to realize a class-E ILO. Finally, 1Χ4 ILO array is constructed and measured. 　　Due to the characteristic of the class-E circuit, the supply voltage is directly proportional to the output voltage. When all elements of array are injection-locked by the external signal, the output power of each ILO can be adjusted by the supply voltage. On the other hand, according to the lock-in time property of injection-locking, the output phase of each ILO can be adjusted by the tuning voltage applied to the varactor in the tank. Then, a local oscillator phased array with tunable output magnitude and phase is accomplished.

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31

Nalumakkal, Priya Suresh. "Ultrawideband and wide-angle scan antenna element and small active phased arrays". Thesis, 2023. https://etd.iisc.ac.in/handle/2005/6157.

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Wideband, wide-scan active phased arrays (APA) are widely used for multi-function radars, communication and electronic warfare. Although considerable research is available on the design and analysis of such antenna elements and arrays with large aperture, multi-octave wide scan phased antenna arrays with an electronically small aperture finds major application in electronic warfare (EW), is not well-developed. Based on a detailed literature survey on ultrawideband antenna for the wideband APA this research began with investigating different designs of tapered slot antenna (TSA) elements. A study of the performance parameters like bandwidth, beamwidth, cross-polarization and beam-squint have been conducted for candidate antenna elements such as microstrip fed TSA, balanced antipodal TSA and stripline fed TSA (STSA). Based on these studies, STSA was selected as the most suitable candidate for meeting the requirement for antenna element. An STSA element with a wide beamwidth of 120° in H-plane with reflection coefficient less than -10 dB is designed. Two different antenna arrays are proposed in this research to demonstrate the advantages of STAS as small aperture active array element for wideband phased arrays. Challenges in the design, analysis and characterization of moderately sized phased arrays using STSA element have been analyzed. Although seof interest in literature, of these a linear active phased array antenna that operates across 6 to 18 GHz frequency range, an array with wide-scan coverage of ±60° in H-plane is not developed. The element pattern in phased arrays causes a squint in the main beam away from broadside. For small phased arrays this can be reduced by on-line calibration by taking a sample of signal at each element of the array. Therefore STSA is integrated with a -20 dB asymmetrical coupler at the feed for calibration and performance monitoring. In addition, the proposed STSA with integrated coupler is designed to have a wideband transition which allows a direct 50 Ω stripline feed. The isolated port of the coupler is internally terminated with a resistor using Ohmegaply resistive layer to improve reliability in airborne platform. A linear array of 16 elements is designed and experimentally demonstrated. The main figure of merit of the array is realised gain of the array over the scan angle. A minimum element gain of 0 dB in array environment is obtained over the scan angle of ±60°, without any grating lobes at high frequency. It also demonstrated a cross-polarization of better than -25 dB at boresight and beam squint less than 1°. A staggered feeding arrangement is incorporated to accommodate the physical dimensions of connectors for minimum inter element spacing. Conventionally the centre element pattern in array environment is used for obtaining the scanning characteristics of a large phased array. But, for small phased array, since the edge effects may be significant an average scan element pattern is proposed for array characterization. This gives an accurate result for the scan characteristics of array and can be used to correct array synthesis before full scale fabrication. This approach is validated by measuring the array pattern of the fabricated array with transmit/receive module. Second, an 8 element E-plane array operating over 1 to 6 GHz frequency range is proposed with scanning of 45° from broadside. This antenna covers D, E, F and G bands of EW system. A novel STSA has been investigated across this bandwidth. Here the radiating part of tapered slot antenna is ended with an elliptical stub instead of circular stub which gives the same performance that of circular stub with reduced overlap with the radial stripline stub. A compact broadband Wilkinson power divider feed network is designed along with array to characterise this. These edge effects are more severe in this array, especially at the low frequency of the operation band and methods to overcome this are investigated. Approaches of additional dummy edge elements or modifying edge elements have been investigated by simulations to reduce edge effects. An approach of adding 3D caps at the edges has been found to be more effective in this regard. To summarize, methods for designing high performance multi-octave stripline fed tapered slot antenna elements and their arrays in the E- and H-plane have been developed using simulations and validated by experiments. These antennas are particularly suited as small aperture arrays in EW applications.

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32

Huang, Ting-Jui, i 黃廷瑞. "Implementation of RF Transceivers in an Active Phased Array Antenna Systems using Tapered Slot Elements". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/83594302650929185863.

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碩士
元智大學
通訊工程學系
99
The main objective of this research focused on the development of antenna array design technologies intended for active phased array antenna systems. Modular approach for sub-array designs was adopted to provide an efficient way for building a practical antenna array system with large number of elements. For practical implementation, each sub-array with 8 basic units was fabricated on a printed circuit board to integrate with RF transceivers and formed a basic module. Necessary phase shifts for corresponding sub-arrays were also applied to realize beam-steering effect required by the system. For the convenience of system performance test, the beam switching block of the receiver consisted of 4 sub-arrays (each 1-by-8) with various phase shifts connected through SPQT switches. The RF front end consisted of low noise amplifier in series with a mixer to down convert the frequency to 2.4GHz. The down converted signal was then fed into VN6000 for baseband processing. On the contrary, at the transmitting side, IF modulated signal was fed through mixer and up-converted to 12.45 GHz to be amplified by power amplifier for transmission by the antenna arrays. 1-by-8 antenna array was used as the transmitting antenna such that the beamwidth of the transmitted signals can be narrow which makes it easy to verify the beam-switching performance at the receiver. Details for practical implementation in system level together with possibe solutions in the suppression of backlobes will be discussed in detail in the thesis.

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33

Chanh, Yu-Cheng, i 張育誠. "Actived phased array radar with phase shifting in baseband". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/69644110879111973688.

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碩士
國立交通大學
電子工程學系電子研究所
103
In convention, the military radar is mechanical, it receives the signal by rotating the antenna. The motion costs long time. Since the speed of detecting is very important in military, the method is left gradually. Electronic radar is presented, the phased array is the popular one. It receives signal at unique direction with some gain by circuits. Without rotating, it is faster than the conventional radar. This paper will introduce a 35 GHz 65nm CMOS scalable four-element phased array. The phased array receiver utilizes a homodyne topology and locate the phase shifter in baseband. The system also uses direct-coupled standing wave oscillator array to simplify the LO routing. Single receiver chain has 51 dB power gain, a noise figure of 7.3 dB and an OIP3 of 8dBm.

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34

Chen, Yen-Horng, i 陳彥宏. "Active Phase Array using Injection-Locked Oscillators". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/73521465195640455103.

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碩士
國立臺灣大學
電信工程學研究所
89
Injection-locked technique provides an efficient approach to generate stable high frequency signal source and finds its application in phase array. It can be used to achieve synchronous operation of a number of antenna elements, and allow for the manipulation of the phase distribution without additional phase shifting circuit. Hence, in modern microwave and millimeter-wave radar, imaging, and communication systems, the injection-locking technique has the potential to be implemented for intelligent scanning antenna design. From Chapter 2 to Chapter 4, design and experimental results of active phase array using injection-locked oscillators are presented. Each element in the array consists of a voltage controlled oscillator with an input port for injecting the locking signal, and its output port connected to a rectangular patch radiator. In other words, an active antenna integrates the oscillator and antenna on the same substrate. The oscillator is designed using cascode circuit configuration, because it has the characteristics of high power gain and can be conveniently used with injection-locking technique. The transistors used include BFG540 and NE32684A. The phase control of each radiated wave is achieved by varying the DC bias on the transistor and a range of 180o can be acquired. From the measured results of 2- and 4-element active phase arrays, the beam scanning range can be from -32.4o to 26.4o, -28.8o to 31.2o, or -12o to 10.8o. The main beam direction is shown to have a reasonable agreement between simulation and experiment. Since the simple structure of the active phase array using injection-locked oscillators, this approach is well suited for MMIC implementation. In Chapter 5, we design a monolithic Ka-band four-element oscillator array using TRW 0.1μm GaAs HEMT foundry. This array is designed to synchronize oscillators through using a four-way power divider. A four-element rectangular patch antenna array is then connected outside the chip for the radiation. Since the MMIC is still under fabrication, the performance test will be the future work of this study. The active phase array using injection-locked oscillators described in this thesis may find applications in digital communication systems. The array radiation beam direction is defined by properly tuning the VCO voltage of each element, whereas the digital modulation signal is fed though all the injection-locked active antennas.

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35

Huang, Shih-Yung, i 黃世勇. "Active Phase Array Radar TR Modules S-Band Reflection Phase Shifter". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/06332229839325232995.

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碩士
輔仁大學
電子工程學系
97
This thesis presents with experiment and imitate research for main,in the phase array radar TR modules the phase inverter power loss, and reduces the phase error,This design for radar systems operating around 2.4 GHz.To implement the switches for field effect transistors（FET）and a Lange coupler.To anticipate the electric power consumption, and enhances the phase shifter the accuracy.The simulation results showed a phase error of less than 1° and 3° and a loss of less than 1.75 dB and 3.5 dB for the 2- and 4-bit phase shifters Therefore, this research demonstrated one kind of low cost solution, the low error, the low power lose the phase inverter, believed it to the overall phase array radar system potency promotion, has the most direct help and the influence.

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36

Chang, Ralph, i 張希喆. "Ku-Band Phase-Shifterless Beam-Scanning Active Antenna Arrays". Thesis, 1997. http://ndltd.ncl.edu.tw/handle/89099995765311103130.

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碩士
國立交通大學
電信研究所
85
This project is to design, fabrication and measure the Ku-band phase-shifterless beam-scanning active antenna arrays. The beam scanning in linear arrays of antenna-coupled oscillators can operate at desired frequency range with in-phase and stable, then the end elements be slightly detuning frequency to provide continuously phase variation between the elements without phase shifter. Mutual coupling technique is utilized to enable them to synchronize to a common frequency through the phenomenon of injectionThis project is based on the circuit designed by Dr. York*s group of UCSB and Prof. Itoh*s group. In this phase- shifterless beam-scanning antennas arrays, it was shown that a constant phase progression can be established by slightly detuning the peripheral arrays elements, while maintaining mutual synchronization.An experiment for the beam-scanning antenna arrays has been carried out. The oscillation frequency is measured at about 16.7 GHz. It has continuously scan the radiation pattern from . An effective radiation power (ERP) of 85mW、349mW、1789mW is obtained for single-unit, two-unit and four-unit active antenna array.

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37

Tsay, Yao-xian, i 蔡耀賢. "An Active Beam-Switching Transmitting Antenna Array And Phase Shifter Designs For 28Ghz Video-Relay System". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/87655719667102630221.

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碩士
國立交通大學
電信工程系
91
Abstract This thesis presents the architecture and circuit design of a high power active beam-steering antenna array for 28GHz Video-Relay System. The antenna array is composed of eight RF transmitters connected with inset-fed patch antennas. Each RF transmitter includes an MMIC power amplifier, a driver amplifier and a sub-harmonic Mixer with image rejection filter. The active array utilizes these 8 MMIC power amplifiers to transmit high power. On the other hand, the IF circuitry distributes to the IF signal into eight way so each way passing through phase shifter connects to the mixer in RF transmitter. Thus, the antenna array could switch beam by controlling phase shifter. Finally, in order to design a miniaturized phase shifter , three type of phase shifter was discussed and fabricated.

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Kandic, Miodrag. "Asymptotic limits of negative group delay phenomenon in linear causal media". 2011. http://hdl.handle.net/1993/4958.

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Abnormal electromagnetic wave propagation characterized by negative group velocity and consequently negative group delay (NGD) has been observed in certain materials as well as in artificially built structures. Within finite frequency intervals where an NGD phenomenon is observed, higher frequency components of the applied waveform are propagated with phase advancement, not delay, relative to the lower frequency components. These media have found use in many applications that require positive delay compensation and an engineered phase characteristic, such as eliminating phase variation with frequency in phase shifters, beam-squint minimization in phased array antenna systems, size reduction of feed-forward amplifiers and others. The three principal questions this thesis addresses are: can a generic formulation for artificial NGD structures based on electric circuit resonators be developed; is it possible to derive a quantitative functional relationship (asymptotic limit) between the maximum achievable NGD and the identified trade-off quantity (out-of-band gain); and, can a microwave circuit exhibiting a fully loss-compensated NGD propagation in both directions be designed and implemented? A generic frequency-domain formulation of artificial NGD structures based on electric circuit resonators is developed and characterized by three parameters, namely center frequency, bandwidth and the out-of-band gain. The developed formulation is validated through several topologies reported in the literature. The trade-off relationship between the achievable NGD on one hand, and the out-of-band gain on the other, is identified. The out-of-band gain is shown to be proportional to transient amplitudes when waveforms with defined “turn on/off” times are propagated through an NGD medium. An asymptotic limit for achievable NGD as a function of the out-of-band gain is derived for multi-stage resonator-based NGD circuits as well as for an optimally engineered linear causal NGD medium. Passive NGD media exhibit loss which can be compensated for via active elements. However, active elements are unilateral in nature and therefore do not allow propagation in both directions. A bilateral gain-compensated circuit is designed and implemented, which overcomes this problem by employing a dual-amplifier configuration while preserving the overall circuit stability.

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Abdalla, Mohamed. "Metamaterial-Inspired CMOS Tunable Microwave Integrated Circuits For Steerable Antenna Arrays". Thesis, 2009. http://hdl.handle.net/1807/17720.

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This thesis presents the design of radio-frequency (RF) tunable active inductors (TAIs) with independent inductance (L) and quality factor (Q) tuning capability, and their application in the design of RF tunable phase shifters and directional couplers for wireless transceivers. The independent L and Q tuning is achieved using a modided gyrator-C architecture with an additional feedback element. A general framework is developed for this Q- enhancement technique making it applicable to any gyrator-C based TAI. The design of a 1.5V, grounded, 0.13um CMOS TAI is presented. The proposed circuit achieves a 0.8nH-11.7nH tuning range at 2GHz, with a peak-Q in excess of 100. Furthermore, printed and integrated versions of tunable positive/negative refractive index (PRI /NRI) phase shifters, are presented in this thesis. The printed phase shifters are comprised of a microstrip transmission-line (TL) loaded with varactors and TAIs, which, when tuned together, extends the phase tuning range and produces a low return loss. In contrast, the integrated phase shifters utilize lumped L-C sections in place of the TLs, which allows for a single MMIC implementation. Detailed experimental results are presented in the thesis. As an example, the printed design achieves a phase of -40 to +34 degrees at 2.5GHz. As another application for the TAI, a reconfigurable CMOS directional coupler is presented in this thesis. The proposed coupler allows electronic control over the coupling coefficient, and the operating frequency while insuring a low return loss and high isolation. Moreover, it allows switching between forward and backward operation. These features, combined together, would allow using the coupler as a duplexer to connect a transmitter and a receiver to a single antenna. Finally, a planar electronically steerable patch array is presented. The 4-element array uses the tunable PRI/NRI phase shifters to center its radiation about the broadside direction. This also minimizes the main beam squinting across the operating bandwidth. The feed network of the array uses impedance transformers, which allow identical interstage phase shifters. The proposed antenna array is capable of continuously steering its main beam from -27 to +22 degrees of the broadside direction with a gain of 8.4dBi at 2.4GHz.

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(9356939), Jui-wei Tsai. "Digital Signal Processing Architecture Design for Closed-Loop Electrical Nerve Stimulation Systems". Thesis, 2020.

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Electrical nerve stimulation (ENS) is an emerging therapy for many neurological disorders. Compared with conventional one-way stimulations, closed-loop ENS approaches increase the stimulation efficacy and minimize patient's discomfort by constantly adjusting the stimulation parameters according to the feedback biomarkers from patients. Wireless neurostimulation devices capable of both stimulation and telemetry of recorded physiological signals are welcome for closed-loop ENS systems to improve the quality and reduce the costs of treatments, and real-time digital signal processing (DSP) engines processing and extracting features from recorded signals can reduce the data transmission rate and the resulting power consumption of wireless devices. Electrically-evoked compound action potential (ECAP) is an objective measure of nerve activity and has been used as the feedback biomarker in closed-loop ENS systems including neural response telemetry (NRT) systems and a newly proposed autonomous nerve control (ANC) platform. It's desirable to design a DSP engine for real-time processing of ECAP in closed-loop ENS systems.

This thesis focuses on developing the DSP architecture for real-time processing of ECAP, including stimulus artifact rejection (SAR), denoising, and extraction of nerve fiber responses as biomedical features, and its VLSI implementation for optimal hardware costs. The first part presents the DSP architecture for real-time SAR and denoising of ECAP in NRT systems. A bidirectional-filtered coherent averaging (BFCA) method is proposed, which enables the configurable linear-phase filter to be realized hardware efficiently for distortion-free filtering of ECAPs and can be easily combined with the alternating-polarity (AP) stimulation method for SAR. Design techniques including folded-IIR filter and division-free averaging are incorporated to reduce the computation cost. The second part presents the fiber-response extraction engine (FREE), a dedicated DSP engine for nerve activation control in the ANC platform. FREE employs the DSP architecture of the BFCA method combined with the AP stimulation, and the architecture of computationally efficient peak detection and classification algorithms for fiber response extraction from ECAP. FREE is mapped onto a custom-made and battery-powered wearable wireless device incorporating a low-power FPGA, a Bluetooth transceiver, a stimulation and recording analog front-end and a power-management unit. In comparison with previous software-based signal processing, FREE not only reduces the data rate of wireless devices but also improves the precision of fiber response classification in noisy environments, which contributes to the construction of high-accuracy nerve activation profile in the ANC platform. An application-specific integrated circuit (ASIC) version of FREE is implemented in 180-nm CMOS technology, with total chip area and core power consumption of 19.98 mm² and 1.95 mW, respectively.

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