Waveform Design for MIMO Radar and SAR Application

Remote sensing applications using radar systems require specific signal processing to obtain high resolution for radar imagery. This high resolution is essential in detection and imaging processing and is provided by using synthetic aperture radar (SAR) processing. This chapter describes the application of the multiple-input multiple-output (MIMO) configuration and the orthogonal frequency-division multiplexing (OFDM) concept to overcome some existing limitations with conventional imaging systems as well as to assess the improvements achieved

Environmental monitoring with the imaging MIMO radars MIRA-CLE and MIRA-CLE X

Several applications need imaging sensors for environmental monitoring which can continuously observe an area in a 24/7 mode independently from the weather and other atmospheric obscuration like dust and smoke. Imaging MIMO radar fulfills these requirements and enables the opportunity of low-cost and robust imaging systems by synthesizing many virtual antennas out of just a few real ones. MIRA-CLE is a fully configurable and expandable experimental MIMO radar in Ka-band while MIRA-CLE X works in X-band and is intended to be a low-cost experimental system for long range applications. This paper presents both MIMO radar systems and shows and discusses first imaging results of MIRA-CLE X

Drones Detection Using Smart Sensors

Drones are modern and sophisticated technology that have been used in numerous fields. Nowadays, many countries use them in exploration, reconnaissance operations, and espionage in military operations. Drones also have many uses that are not limited to only daily life. For example, drones are used for home delivery, safety monitoring, and others. However, the use of drones is a double-edged sword. Drones can be used for positive purposes to improve the quality of human lives, but they can also be used for criminal purposes and other detrimental purposes. In fact, many countries have been attacked by terrorists using smart drones. Hence, drone detection is an active area of research and it receives the attention of many scholars. Advanced drones are, many times, difficult to detect, and hence they, sometimes, can be life threatening. Currently, most detection methods are based on video, sound, radar, temperature, radio frequency (RF), or Wi-Fi techniques. However, each detection method has several flaws that make them imperfect choices for drone detection in sensitive areas. Our aim is to overcome the challenges that most existing drone detection techniques face. In this thesis, we propose two modeling techniques and compare them to produce an efficient system for drone detection. Specifically, we compare the two proposed models by investigating the risk assessments and the probability of success for each model

Étude et réalisation d'un système d'imagerie SAR exploitant des signaux et configurations de communication numérique

The work presented in this thesis focuses on the design and implementation of a SAR system operating with two Digital Communications technology: MIMO configuration and OFDM signals. In the first part of this study, various methods for focusing received signals for MIMO configuration are proposed in order to measure the impact of the MIMO configuration on the robustness. In addition, the impact of the MIMO configuration on the azimuth resolution is measured. Finally, an experimental system is developed in order to validate the results obtained by simulation. In the second part of this study, a range ambiguity suppression method is proposed and validated by simulation. However, the use of conventional chirp signals showed the limits of its use for the range ambiguity suppression. Thus, a design method of OFDM signals is developed in order to solve this problem. The last study on the OFDM signals is carried out in the context of its use with the MIMO configuration. The impact of the OFDM signals on the azimuth resolution and the imaging quality parameters are studied.Les travaux présentés dans cette thèse portent sur l'étude et la réalisation d'un système d'imagerie SAR (synthetic aperture radar) exploitant deux techniques provenant des communications numériques: la configuration MIMO et les signaux OFDM. Dans la première partie de cette étude, différentes méthodes de focalisation des signaux reçus pour la configuration MIMO sont proposées afin de mesurer l'impact de la configuration MIMO sur la robustesse du système d'imagerie SAR par rapport aux bruits. Par ailleurs, on mesure aussi l'impact de la configuration MIMO sur la résolution en azimut. Finalement, un système expérimental est développé au sein du laboratoire afin de confirmer les résultats obtenus par simulation. Dans la deuxième partie de cette étude, une méthode de réduction de l'ambiguïté en distance est proposée et validée par simulation. Cependant, l'utilisation de signaux classiques de type \textit{chirps} montre ses limites pour la réduction de l'ambiguïté en distance. Ainsi, une méthode de conception de signaux OFDM est développée afin de résoudre ce problème. Une dernière étude sur les signaux OFDM est mené dans le cadre de son utilisation dans la configuration MIMO pour l'imagerie SAR. L'impact des signaux OFDM sur la résolution azimutale ainsi que sur les différents paramètres de qualité images est étudié

Étude et réalisation d'un système d'imagerie SAR exploitant des signaux et configurations de communication numérique

The work presented in this thesis focuses on the design and implementation of a SAR system operating with two Digital Communications technology: MIMO configuration and OFDM signals. In the first part of this study, various methods for focusing received signals for MIMO configuration are proposed in order to measure the impact of the MIMO configuration on the robustness. In addition, the impact of the MIMO configuration on the azimuth resolution is measured. Finally, an experimental system is developed in order to validate the results obtained by simulation. In the second part of this study, a range ambiguity suppression method is proposed and validated by simulation. However, the use of conventional chirp signals showed the limits of its use for the range ambiguity suppression. Thus, a design method of OFDM signals is developed in order to solve this problem. The last study on the OFDM signals is carried out in the context of its use with the MIMO configuration. The impact of the OFDM signals on the azimuth resolution and the imaging quality parameters are studied.Les travaux présentés dans cette thèse portent sur l'étude et la réalisation d'un système d'imagerie SAR (synthetic aperture radar) exploitant deux techniques provenant des communications numériques: la configuration MIMO et les signaux OFDM. Dans la première partie de cette étude, différentes méthodes de focalisation des signaux reçus pour la configuration MIMO sont proposées afin de mesurer l'impact de la configuration MIMO sur la robustesse du système d'imagerie SAR par rapport aux bruits. Par ailleurs, on mesure aussi l'impact de la configuration MIMO sur la résolution en azimut. Finalement, un système expérimental est développé au sein du laboratoire afin de confirmer les résultats obtenus par simulation. Dans la deuxième partie de cette étude, une méthode de réduction de l'ambiguïté en distance est proposée et validée par simulation. Cependant, l'utilisation de signaux classiques de type \textit{chirps} montre ses limites pour la réduction de l'ambiguïté en distance. Ainsi, une méthode de conception de signaux OFDM est développée afin de résoudre ce problème. Une dernière étude sur les signaux OFDM est mené dans le cadre de son utilisation dans la configuration MIMO pour l'imagerie SAR. L'impact des signaux OFDM sur la résolution azimutale ainsi que sur les différents paramètres de qualité images est étudié

Advanced Techniques for Ground Penetrating Radar Imaging

Ground penetrating radar (GPR) has become one of the key technologies in subsurface sensing and, in general, in non-destructive testing (NDT), since it is able to detect both metallic and nonmetallic targets. GPR for NDT has been successfully introduced in a wide range of sectors, such as mining and geology, glaciology, civil engineering and civil works, archaeology, and security and defense. In recent decades, improvements in georeferencing and positioning systems have enabled the introduction of synthetic aperture radar (SAR) techniques in GPR systems, yielding GPR–SAR systems capable of providing high-resolution microwave images. In parallel, the radiofrequency front-end of GPR systems has been optimized in terms of compactness (e.g., smaller Tx/Rx antennas) and cost. These advances, combined with improvements in autonomous platforms, such as unmanned terrestrial and aerial vehicles, have fostered new fields of application for GPR, where fast and reliable detection capabilities are demanded. In addition, processing techniques have been improved, taking advantage of the research conducted in related fields like inverse scattering and imaging. As a result, novel and robust algorithms have been developed for clutter reduction, automatic target recognition, and efficient processing of large sets of measurements to enable real-time imaging, among others. This Special Issue provides an overview of the state of the art in GPR imaging, focusing on the latest advances from both hardware and software perspectives

Multimedia Context Awareness for Smart Mobile Environments

openNowadays the development of the IoT framework and the resulting huge number of smart connected devices opens the door to exploit the presence of multiple smart nodes to accomplish a variety of tasks. Multimedia context awareness, together with the concept of ambient intelligence, is tightly related to the IoT framework, and it can be applied to a large number of smart scenarios. In this thesis, the aim is to study and analyze the role of context awareness in different applications related to smart mobile environments, such as future smart spaces and connected cities. Indeed, this research work focuses on different aspects of ambient intelligence, such as audio-awareness and wireless-awareness. In particular, this thesis tackles two main research topics: the first one, related to the framework of audio-awareness, concerns a multiple observations approach for smart speaker recognition in mobile environments; the second one, tied to the concept of wireless-awareness, regards Unmanned Aerial Vehicle (UAV) detection based on WiFi statistical fingerprint analysis.openXXXI CICLO - SC. E TECN. ING. ELETTR. E DELLE TEL. - Ambienti cognitivi interattiviGaribotto, Chiar

Safety and Reliability - Safe Societies in a Changing World

The contributions cover a wide range of methodologies and application areas for safety and reliability that contribute to safe societies in a changing world. These methodologies and applications include: - foundations of risk and reliability assessment and management - mathematical methods in reliability and safety - risk assessment - risk management - system reliability - uncertainty analysis - digitalization and big data - prognostics and system health management - occupational safety - accident and incident modeling - maintenance modeling and applications - simulation for safety and reliability analysis - dynamic risk and barrier management - organizational factors and safety culture - human factors and human reliability - resilience engineering - structural reliability - natural hazards - security - economic analysis in risk managemen