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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

FUSION OF VIDEO AND MULTI-WAVEFORM FMCW RADAR FOR TRAFFIC SURVEILLANCE

Gale, Nicholas C. 19 September 2011 (has links)
No description available.
42

A Low-Power Multiprocessor Systems-on-Chip Architecture for Smart Dense Radars

Gonzalez Diaz, Hector A. 22 October 2024 (has links)
Highly dense Multiple-Input Multiple-Output (MIMO) radars provide robust detection at a high angular resolution in automotive applications. However, these systems require extensive parallel processing, higher off-chip communication data rates, and higher power consumption as a result of denser arrays to tackle. In this work, concepts, algorithms and circuits for the first-in-literature System-on-Chip (SoC) performing on-chip 5D localization of targets are researched and developed. The targeted system features a scalable homogeneous architecture for fully integrated signal processing of Frequency Modulated Continuous Wave (FMCW) signals and near-sensor smart capabilities for the identification of critical targets (e.g., pedestrians) in an automotive context. To achieve this functionality at a low-power budget, the interconnection of locally constrained processing nodes each with low-area and low-power accelerators operating at low frequencies is developed. The design of efficient algorithms, data flow, and cognitive concepts is also researched and presented to provide an unconventional holistic co-design approach. As a result of the research carried out in this thesis, a 12-ADC multi-core Digital Signal Processor (DSP) in 22FDX GLOBALFOUNDRIES (GF) using Adaptive Body Biasing (ABB) at 0.6V to enable smart on-chip classification with 25 processing elements (PEs) is proposed, providing a low power consumption of only 52.6mW that is at least 90x lower than the state-of-the-art commercial MIMO Radar DSPs.:Abstract Zusammenfassung List of Figures List of Tables Nomenclature 1. Introduction 1.1. Introduction 1.2. Motivation 1.3. Aims and Objectives 1.4. Contributions 1.5. Publications 1.6. Thesis Outline 2. Signal Processing for 5D Radars 2.1. Signal Processing Overview 2.2. Velocity Disambiguation Proposals for MIMO Radars 2.3. Cognitive Principles 2.4. Proposed Clustering for Constrained Processors 2.5. Target Classification 2.6. Summary of the Proposed Contributions 3. Hardware for 5D Radars: A Prototype Implementation 3.1. Multiprocessor Systems-on-Chip 3.2. FFT Acceleration 3.3. Silicon Implementation 3.4. Proposed Testchip 3.5. Proposed Implementation of the Processing Stages 3.6. Summary of Contributions 4. Conclusion and Outlook 4.1. Summary 4.2. Applications 4.3. Further Work 4.4. Conclusion A. Appendix A.1. FMCW Equations A.2. Dataset for Velocity Disambiguation A.3. Dataset for Machine Learning A.4. Dataset for Cognitive Radar Mode A.5. Reliability Proof for the Ambiguity Detector A.6. Measurement Setup A.7. EDA Tools Used in this Work Publications Bibliography / Hochdichte MIMO-Radar-Systeme bieten robuste Detektion mit hoher Winkelauflösung in Automobilanwendungen. Diese Systeme erfordern jedoch aufgrund dichterer Arrays umfangreiche parallele Verarbeitung, höhere Datenraten für die Off-Chip-Kommunikation und einen höheren Stromverbrauch. In dieser Arbeit werden Konzepte, Algorithmen und Schaltungen für den erstmaligen SoC-Ansatz zur On-Chip-Lokalisierung von Zielen in fünf Dimensionen untersucht und entwickelt. Das angestrebte System zeichnet sich durch eine skalierbare homogene Architektur für die vollständig integrierte Signalverarbeitung von FMCW-Signalen aus sowie durch intelligente Fähigkeiten in der Nähe des Sensors zur Identifizierung kritischer Ziele (z. B. Fußgänger) im automobilen Kontext. Um diese Funktionalität bei geringem Energieverbrauch zu erreichen, wird die Verbindung von lokal begrenzten Verarbeitungsknoten mit niedrigflächigen und energieeffizienten Beschleunigern entwickelt, die bei niedrigen Frequenzen arbeiten. Des Weiteren werden effiziente Algorithmen, Datenflüsse und kognitive Konzepte erforscht und präsentiert, um einen unkonventionellen ganzheitlichen Co-Design-Ansatz zu bieten. Als Ergebnis der in dieser Arbeit durchgeführten Forschung wird ein 12-ADC-Multi-Core-DSP in 22FDX GF mit ABB bei 0,6V vorgeschlagen, um eine intelligente On-Chip-Klassifizierung mit 25 Verarbeitungselementen (PEs) zu ermöglichen. Dieser Prozessor weist einen geringen Stromverbrauch von lediglich 52,6mW auf, der mindestens 90-mal niedriger ist als bei den modernsten kommerziellen MIMO-Radar-DSPs.:Abstract Zusammenfassung List of Figures List of Tables Nomenclature 1. Introduction 1.1. Introduction 1.2. Motivation 1.3. Aims and Objectives 1.4. Contributions 1.5. Publications 1.6. Thesis Outline 2. Signal Processing for 5D Radars 2.1. Signal Processing Overview 2.2. Velocity Disambiguation Proposals for MIMO Radars 2.3. Cognitive Principles 2.4. Proposed Clustering for Constrained Processors 2.5. Target Classification 2.6. Summary of the Proposed Contributions 3. Hardware for 5D Radars: A Prototype Implementation 3.1. Multiprocessor Systems-on-Chip 3.2. FFT Acceleration 3.3. Silicon Implementation 3.4. Proposed Testchip 3.5. Proposed Implementation of the Processing Stages 3.6. Summary of Contributions 4. Conclusion and Outlook 4.1. Summary 4.2. Applications 4.3. Further Work 4.4. Conclusion A. Appendix A.1. FMCW Equations A.2. Dataset for Velocity Disambiguation A.3. Dataset for Machine Learning A.4. Dataset for Cognitive Radar Mode A.5. Reliability Proof for the Ambiguity Detector A.6. Measurement Setup A.7. EDA Tools Used in this Work Publications Bibliography
43

Evaluation of FMCW Radar Jamming Sensitivity

Snihs, Ludvig January 2023 (has links)
In this work, the interference sensitivity of an FMCW radar has been evaluated by studying the impact on a simulated detection chain. A commercially available FMCW radar was first characterized and its properties then laid the foundation for a simulation model implemented in Matlab. Different interference methods have been studied and a selection was made based on the results of previous research. One method aims to inject a sufficiently large amount of energy in the form of pulsed noise into the receiver. The second method aims to deceive the radar into seeing targets that do not actually exist by repeating the transmitted signal and thus giving the radar a false picture of its surroundings. The results show that if it is possible to synchronize with the transmitted signal then repeater jamming can be effective in misleading the radar. In one scenario the false target even succeeded in hiding the real target by exploiting the Cell-Averaging CFAR detection algorithm. The results suggests that without some smart countermeasures the radar has no way of distinguishing a coherent repeater signal, but just how successful the repeater is in creating a deceptive environment is highly dependent on the detection algorithm used. Pulsed noise also managed to disrupt the radar and with a sufficiently high pulse repetition frequency the detector could not find any targets despite a simulated object in front of the radar. On the other hand, a rather significant effective radiated power level was required for the pulse train to achieve any meaningful effect on the radar, which may be due to an undersampled signal in the simulation. It is therefore difficult based on this work to draw any conclusions about how suitable pulsed noise is in a non-simulated interference context and what parameter values to use.
44

Concept de radars novateurs pour la vision à travers les milieux opaques / Innovative radar concept for through-the-wall applications

Merelle, Vincent 19 September 2018 (has links)
La « vision » à travers les milieux opaques (murs, cloisons, décombres, ou plus généralement tout milieu qui occulte la vision humaine) est l’un des problèmes clefs du contrôle et de la sécurité. Il apparaît à l’heure actuelle un réel besoin de disposer de dispositifs d’observation à travers ces milieux pour des applications tant militaires (lors des assauts, des prises d’otages, etc.) que civiles (recherche de personnes enfouies dans des décombres, dans un incendie, etc). Les avancées sur cette problématique ont conduit à mettre en place des systèmes radars à très courte portée, opérationnels pour la détection et le tracking de personnes dans des environnements simples. Cependant ils nécessitent que les cibles soient en déplacement afin de les différencier des objets statiques. Cette limitation constitue un défaut majeur pour un certain nombre de scénarii réels où des personnes, par stratégie ou par contrainte, restent immobiles. Ces travaux de thèse visent à explorer les mécanismes de détection de personnes statiques par le biais de leurs micro-mouvements, e.g. des mouvements induits par le thorax lors de la respiration. Nous avons étudié - d’un point de vue théorique - les principes physiques sous-jacents à la détection de ces micro-mouvements par radar UWB impulsionnel à partir du mécanisme Doppler impulsionnel. Ce dernier s’appuie sur des mesures consécutives des phases des impulsions réfléchies. La compréhension de ce phénomène a permis de définir une architecture radar impulsionnelle et de la positionner, en termes de contributions, au regard des différents radars UWB proposés dans la littérature : le FMCW et le radar de bruit. Deux dispositifs radars ont servi de support à ce travail. Le premier, de type démonstrateur académique, repose sur l’utilisation d’un oscilloscope rapide pour numériser les impulsions UWB de 3 à 6 GHz de bande. Il a permis de mettre en place une chaîne de traitement complète de vision à travers les murs. Le second dispositif est un prototype radar développé autour d’une plateforme de numérisation ultra-rapide (100 Gsps par échantillonnage équivalent) de fréquence de rafraîchissement très élevée (100 Hz). Il est construit autour d’un FPGA, d’un ADC rapide (1,25 GHz) et d’un T&H très large bande (18 GHz). Il permet ainsi la détection des micro-mouvements par traitement Doppler impulsionnel. / "Vision" through opaque environments (walls, partitions, rubble, or any environment that obscures human vision) is one of the key issues of control and security. Advances on this issue have led to operational shortrange radar systems for people detection and tracking in simple environments. However, most of them require the targets to move in order to differentiate them from static objects. This requirement constitues a major shortcoming for a certain number of real scenarios where people, by strategies or by constraints, remain motionless. Hence, this thesis aims to explore the mechanisms of detection of static people through their micro-movements, e.g. movements induced by the thorax during breathing. We have studied - from a theoretical point of view - the physical principles underlying the detection of these micro-movements by pulsed UWB radar with the pulsed Doppler phenomenon, which relies on consecutive measurements of the reflected pulses phases. The understanding of this phenomenon made it possible to define a radar architecture and to position it, in terms of contributions, with regard to the different UWB radars proposed in the literature : the FMCW and the noise radar. Two radar devices served as support for this work. An academic demonstrator based on the use of a fast oscilloscope to digitize the pulses. It allowed to set up a complete processing chain for the application of vision through the walls. The second device is a radar prototype developed around a high-speed scanning platform (100 Gsps perequivalent sampling) with a very high refresh rate (100 Hz). This prototype is built around an FPGA, a fast ADC (1.25 GHz) and a very wide band T&H (18 GHz). This thereby enables to detect micro-movements by pulsed Doppler processing.
45

Radar-based Environment Perception for Pre-Crash Safety Systems

Kamann, Alexander 15 January 2021 (has links)
In this thesis, methods for radar-based environment perception from the vehicle safety point of view are presented. The proposed methods comprise advanced topics of radar-based target detection and tracking in dynamic pre-crash scenarios, as well as ghost object identification. The problem of a wandering dominant scatter point on the target surface and corresponding challenge for accurate target tracking in low-range configurations is considered. The proposed method presents a procedure to estimate target wheel positions and corresponding bulk velocities to serve as fixed scatter points on the target surface. Input to this method are raw radar data. The technique spatially resolves the micro-Doppler signals, generated by the rotating wheels of the target vehicle, to determine characteristic scatter points on the target surface. A micro-Doppler parameter is defined to quantify detections that are with high probability generated by the rotating target wheels. This group of detections is processed to estimate the wheel position and corresponding bulk velocities of the target, referred to as wheel hypotheses. The proposed method is evaluated in dynamic driving scenarios, where the driver performs an emergency evading action to avoid a collision. Subsequently, the detected wheel hypotheses serve as input to a developed tracking framework, which is used to estimate the target object static and dynamic states. Since the number of detected wheel hypotheses varies, a random-finite-set-based measurement model is used to incorporate multiple wheel hypotheses detected for one extended target object. The tracking performance is evaluated in critical evading scenarios using real vehicles as the target object. In addition, the thesis emphasized the problem of ghost object generation due to multipath propagation in pre-crash scenarios. Radar sensors, perceiving the immediate vehicle environment, show an elevated ghost object presence due to a higher probability illuminating potential reflection surfaces, e.g., road boundaries or buildings. At times, these ghost objects appear to be on a collision trajectory with the ego vehicle, whereas the vehicles are in uncritical driving scenarios, e.g., an urban intersection. In real-world driving scenarios, one target object may generate multiple false-positive targets. Based on the propagation and reflection behavior of electromagnetic waves, a geometric multipath model is derived, illustrating the occurring multipath reflections on real-world surfaces, e.g., buildings or road-bounding barriers. The proposed geometric propagation model describes the relative positions of the false-positive reflections and is validated with extensive real radar data. A custom reflector target mounted on a platform, creating deterministic point targets as dominant backscatter centers of a vehicle body, validated the different multipath reflections and the overall accuracy of the model. Moreover, radar measurements of a vehicle during an intersection scenario proved relevance to multipath reflection behavior and confirmed the model assumptions. Third, the relevance of skid scenarios with high magnitudes of side slip angles in pre-crash phases is highlighted. A novel test methodology, to non-destructively transfer vehicles with mounted surround sensors in skid situations, is developed and a survey analyzing a state-of-the-art radar sensor revealed the potential to improve object tracking performance. A test vehicle, equipped with a state-of-the-art automotive radar sensor and a reference sensor, was tested in real skid situations using a kick plate and a standardized radar target. The test method utilizes the side slip angle as a criticality criterion, which may be adjusted by the kick plate. Subsequently, a novel, modified motion model is derived, estimating side slip angles in these skid driving situations. The contribution emphasizes the estimation of horizontal vehicle motion using the proposed model considering an additional lateral force applied to the vehicle rear axle. Based on these results, an Extended-Kalman filter is designed to estimate the target object relative position and velocity in skid scenarios. The evaluation includes both the tracking and side slip angle estimations in real car tests using the above-mentioned test method.
46

A K-band SiGe Super-Regenerative Amplifier for FMCW Radar Active Reflector Applications

Thayyil, Manu Viswambharan, Li, Songhui, Joram, Niko, Ellinger, Frank 22 August 2019 (has links)
A K-band integrated super-regenerative amplifier (SRA) in a 130nm SiGe BiCMOS technology is designed and characterized. The circuit is based on a novel stacked transistor differential cross-coupled oscillator topology, with a controllable tail current for quenching the oscillations. The fabricated integrated circuit (IC) occupies an area of 0.63mm2, and operates at the free-running center frequency of 25.3 GHz. Characterization results show circuit operation from a minimum input power level required for a phase coherent output as −110 dBm, and the input power level corresponding to the linear to logarithmic mode transition of −85 dBm, the lowest reported for K-band integrated logarithmic mode SRAs to date to the knowledge of the authors. The measured output power is 7.8dBm into a 100 differential load. The power consumption of the circuit is 110mW with no quench signal applied, and 38mW with 30 % duty cycle quenching. The quench waveform designed for the reported measurement result is also discussed.
47

Simulation of FMCW mode MIMO Radar for Performance Analysis as Industrial Safety System

Prakash, Jay January 2021 (has links)
In industrial environments workers can be prone to dangerous situations that may cause harm. In order to prevent accidents and fulfill legislative requirements for safe working condition, a safety system can be needed to be installed in place. In an attempt to bring a principal improvement in the safety standards offered by conventional systems in existence, a radar sensor is proposed for the detection of dangerous situations. This thesis explores the limiting performance of the radar sensor in an industrial safety system. The radar sensor is an FMCW mode MIMO radar and we develop a model to simulate the radar sensor based on its hardware design. The model is utilized to deduce and analyze the performance limits of the radar sensor, by using a Finite Element Method to determine the electromagnetic scattering response of a target in the operating frequency band, 60-64 GHz. Appropriate dielectric and magnetic properties of human tissue is assigned to obtain accurate scattering responses of a human body target. The performance analysis is done by comparing the reflection from various protruding body parts, with the reflection from the torso, over a wide range of postures of the body. Further, CFAR, a common form of detection algorithm is applied on a few of the postures to detect a protruding part the body. Finally, a discussion on the limited performance is made, and potential methods to enhance the performance of the radar sensor in an industrial safety system are suggested. / I industriella miljöer kan arbetare utsättas för farliga situationer vilka kan orsaka skador. För att förhindra olyckor och uppfylla lagstadgade krav för säkra arbetsförhållanden kan säkerhetssystem behöva installeras på plats. I ett försök att åstadkomma en förbättring av de säkerhetsstandarder som erbjuds av konventionella system föreslås en radarsensor för att detektera farliga situationer. Denna avhandling undersöker möjliga begränsningar i prestanda hos en radarsensor, vilken ingår som komponent i ett industriellt säkerhetssystem. Radarsensorn är en MIMO-radar, som arbetar i FMCW-mod, och vi utvecklar en modell för att simulera radarsensorn utgående ifrån dess hårdvarudesign. Modellen används för att härleda och analysera begränsningar i prestanda hos radarsensorn, genom att med hjälp av finita elementmetoden beräkna spridningen av elektromagnetiska vågor från ett radarmål i frekvensbandet 60-64 GHz. Tillämpliga dielektriska och magnetiska egenskaper hos mänsklig vävnad har använts för att erhålla tillförlitliga data på spridningsresponsen för människokroppen. Prestandaanalysen görs genom att jämföra reflektionen från olika utskjutande kroppsdelar med reflektionen från bålen över ett stort antal kroppshållningar. Vidare, CFAR, en vanlig form av detektionsalgoritm tillämpas på några av hållningarna för att detektera utskjutande delar av kroppen. Avslutningsvis diskuteras begränsningarna i prestandan och potentiella metoder för att förbättra radarsensorns prestanda i ett industriellt säkerhetssystem föreslås.
48

Design and Implementation of a Multipurpose Radar Sensor

Niklasson, Johan, Åström, Axel January 2019 (has links)
This thesis presents the design and implementation of a multifunctional radar sensor. Utilising microstrip transmission line technology, a front-end receiver has been designed based upon a six-port architecture. Additionally, digital signal processing has been implemented on a microcontroller, enabling processing and extraction of information from the down converted quadrature signals. Results have show that the sensor is capable of operating as both a continuous wave radar and frequency modulated continuous wave radar. Through measurements, it has been established that the sensor is capable of wireless measurements, such as vital signs and vibrations. Furthermore, a graphical user interface has been design, allowing a way of switching between different radar configurations and the presentation of measured data to the user.
49

Filterdesign och hårdvarukonstruktion för FMCW-radar

Eriksson, Oscar January 2007 (has links)
<p>Den här högskoleavhandlingen beskriver designen av ett IF-filter samt hårdvarukonstruktion av en ny 77 GHz FMCW-radar demonstrator. Syftet med demonstratorn är att illustrera hur kisel germanium-, SiGe, teknologi kan användas istället för den mer vedertagna men dyrare gallium arsenik-, GaAs, teknologin. Den gamla radar-prototypen vilken Acreo AB utvecklat är funktionell men behöver konstrueras om för att bättre kunna utvärdera radarprestandan. I avhandlingen presenteras grundläggande radarteori och ekvationer för att underlätta förståelsen av de olika systemblocken. Rapporten beskriver också systemarkitekturen och hur dess funktionalitet kommer att testas. Det omdesignade IF-filtret har simulerats i en PSpice-simulator och ett prototypkort av detta har tillverkats för mätningar. Ett 4-lagers kretskort av hela systemet har tagits fram i Orcad Layout. Slutligen innehåller rapporten förslag på förbättringar till nästa demonstratorversion.</p> / <p>This bachelor thesis describes the design of an IF-filter and the hardware construction of a new version of a 77 GHz FMCW-radar demonstrator. The purpose of the demonstrator is to illustrate how the silicon germanium-, SiGe, technology could be used instead of the more conventional but also much more expensive gallium arsenide-, GaAs, technology. The old radar prototype that Acreo AB has developed is fully functional but needs to be redesigned to be able to evaluate the radar performance in a better way. The thesis presents the basic radar theory and equations to help understanding the construction of the system blocks. The report also describes the system architecture and how its functionality should be tested. The redesigned IF-filter has been simulated in a PSpice simulator and a prototype has been manufactured and measured. A 4-layer PCB-board of the whole system was done in Orcad Layout. Finally the report is concluded with suggestions on improvements for the next demonstrator version.</p>
50

Optimization of a 50 MHz Frequency Modulated Continuous Wave radar system for the study of auroral E-region coherent backscatter

Perry, Gareth William 24 August 2010
A 50 MHz Frequency Modulated Continuous Wave (FMCW) radar system, developed at the University of Saskatchewan to provide improved spatial and temporal resolution measurements of auroral E-region plasma processes, introduces ambiguous spectral information, due to spectral ghosting, for scattering events in which multiple radar echoes are detected. This thesis identifies two Linearly Frequency Modulated (LFM) radar waveforms used by the FMCW system as the source of the ghosting. An analysis procedure designed to counteract the spectral ghosting problem is developed but is not an ideal solution, and therefore replacement of the LFM waveforms is recommended.<p> A detailed investigation of alternative radar waveforms using the Ambiguity Function and Ambiguity Diagram techniques is performed. A frequency coded continuous wave radar waveform based on a composite Costas sequence is proposed as a successor to the LFM waveforms. The composite Costas radar waveform will conserve the spatial and temporal resolutions extended by the LFM waveforms and preclude any spectral ghosting. Implementing the proposed radar waveform and avoiding receiver saturation issues with the mono-static FMCW radar system in which both the transmitting and receiving antenna arrays are simultaneously and continuously active and geographically co-located is also discussed.<p> In addition to this, two 50 MHz backscatter events are presented in this thesis to demonstrate the effectiveness of the FMCW system, notwithstanding the spectral ghosting complication. The first event from November 21, 2009 is identified as a Type 1 instability and the second from September 13, 2009 is identified as a Type 2 instability which lasted for ~ 16 minutes. Linear plasma fluid theory is used to provide a brief interpretation of both scattering events.

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