43 research outputs found

    End-to-end security in embedded system for modern mobile communication technologies

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    Modern mobile electronic devices such as smartphones or cell phones can now be used for distant devices such as technical systems to monitor and control. While surveillance systems do not require high standards navigating about the time of transfer of the displayed data. More real-time data are needed for a remote mobile robot transfer. Therefore, it has investigated and measured not only the possibilities of employing mobile devices. But also, the supported data transmission channels, such as UMTS, GSM, Wireless LAN, and Bluetooth. The remotecontrol system is used in many applications such as smart homes, cities, smart hospitals, etc., but it must be today updated to ensure fast-changing technology. Extensive coverage, remote control, and reliable operation in realtime in the deployment of wireless security knowledge. The home automation control system delivers significant features together with a user-friendly interface. A secure remote-based end-to-end security system NTMobile, a technique that enables NAT to provide transverse and encrypted communication from end to end. This confirmed that evaluating the performance of the system in the ECHONET lite compatible smartphone ecosystem. This gives flexibility in configuring time-sensitive industrial networks and enables them to be secured. A safe and reliable remote-control system is also conceivable under the privacy of the user

    Joint Waveform and Clustering Design for Coordinated Multi-point DFRC Systems

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    To improve both sensing and communication performances, this paper proposes a coordinated multi-point (CoMP) transmission design for a dual-functional radar-communication (DFRC) system. In the proposed CoMP-DFRC system, the central processor (CP) coordinates multiple base stations (BSs) to transmit both the communication signal and the dedicated probing signal. The communication performance and the sensing performance are both evaluated by the signal-to-interference-plus-noise ratio (SINR). Given the limited backhaul capacity, we study the waveform and clustering design from both the radar-centric perspective and the communication-centric perspective. Dinkelbach’s transform is adopted to handle the single-ratio fractional objective for the radar-centric problem. For the communication-centric problem, we adopt quadratic transform to convexitify the multi-ratio fractional objective. Then, the rank-one constraint of communication beamforming vector is relaxed by semidefinite relaxation (SDR), and the tightness of SDR is further proved to guarantee the optimal waveform design with fixed clustering. For dynamic clustering, equivalent continuous functions are used to represent the non-continuous clustering variables. Successive convex approximation (SCA) is further utilized to convexitify the equivalent functions. Simulation results are provided to verify the effectiveness of all proposed designs

    Advancing UAV Path Planning System: A Software Pattern Language for Dynamic Environments

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    In the rapidly advancing domain of Unmanned Aerial Vehicle (UAV) technologies, the capability to navigate dynamic and unpredictable environments is paramount. To this end, we present a novel design pattern framework for real-time UAV path planning, derived from the established Pattern Language of Program Community (PLOP). This framework integrates a suite of software patterns, each selected for its role in enhancing UAV operational adaptability, environmental awareness, and resource management. Our proposed framework capitalizes on a blend of behavioral, structural, and creational patterns, which work in concert to refine the UAV's decision-making processes in response to changing environmental conditions. For instance, the Observer pattern is employed to maintain real-time environmental awareness, while the Strategy pattern allows for dynamic adaptability in the UAV's path planning algorithm. Theoretical analysis and conceptual evaluations form the backbone of this research, eschewing empirical experiments for a detailed exploration of the design's potential. By offering a systematic and standardized approach, this research contributes to the UAV field by providing a robust theoretical foundation for future empirical studies and practical implementations, aiming to elevate the efficiency and safety of UAV operations in dynamic environments

    Device discovery in D2D communication: A survey

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    Device to Device (D2D) communication was first considered in out-band to manage energy issues in the wireless sensor networks. The primary target was to secure information about system topology for successive communication. Now the D2D communication has been legitimated in in-band by the 3rd Generation Partnership Project (3GPP). To initiate D2D communication, Device Discovery (DD) is a primary task and every D2D application benefits from DD as an end to end link maintenance and data relay when the direct path is obstructed. The DD is facing new difficulties because of the mobility of the devices over static systems, and the mobility makes it more challenging for D2D communication. For in-band D2D, DD in a single cell and multi-cell, and dense area is not legitimated properly, causing latency, inaccuracy, and energy consumption. Among extensive studies on limiting energy consumption and latency, DD is one of the essential parts concentrating on access and communication. In this paper, a comprehensive survey on DD challenges, for example single cell/multi-cell and dense area DD, energy consumption during discovery, discovery delay, and discovery security, etc., has been presented to accomplish an effective paradigm of D2D networks. In order to undertake the device (user) needs, an architecture has been projected, which promises to overwhelm the various implementation challenges of DD. The paper mainly focuses on DD taxonomy and classification with an emphasis on discovery procedures and algorithms, a summary of advances and issues, and ways for potential enhancements. For ensuring a secure DD and D2D, auspicious research directions have been proposed, based on taxonomy

    Advanced Technique and Future Perspective for Next Generation Optical Fiber Communications

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    Optical fiber communication industry has gained unprecedented opportunities and achieved rapid progress in recent years. However, with the increase of data transmission volume and the enhancement of transmission demand, the optical communication field still needs to be upgraded to better meet the challenges in the future development. Artificial intelligence technology in optical communication and optical network is still in its infancy, but the existing achievements show great application potential. In the future, with the further development of artificial intelligence technology, AI algorithms combining channel characteristics and physical properties will shine in optical communication. This reprint introduces some recent advances in optical fiber communication and optical network, and provides alternative directions for the development of the next generation optical fiber communication technology

    Advances in Intelligent Vehicle Control

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    This book is a printed edition of the Special Issue Advances in Intelligent Vehicle Control that was published in the journal Sensors. It presents a collection of eleven papers that covers a range of topics, such as the development of intelligent control algorithms for active safety systems, smart sensors, and intelligent and efficient driving. The contributions presented in these papers can serve as useful tools for researchers who are interested in new vehicle technology and in the improvement of vehicle control systems

    Long-term localization of unmanned aerial vehicles based on 3D environment perception

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    Los vehículos aéreos no tripulados (UAVs por sus siglas en inglés, Unmanned Aerial Vehicles) se utilizan actualmente en innumerables aplicaciones civiles y comerciales, y la tendencia va en aumento. Su operación en espacios exteriores libres de obstáculos basada en GPS (del inglés Global Positioning System) puede ser considerada resuelta debido a la disponibilidad de productos comerciales con cierto grado de madurez. Sin embargo, algunas aplicaciones requieren su uso en espacios confinados o en interiores, donde las señales del GPS no están disponibles. Para permitir la introducción de robots aéreos de manera segura en zonas sin cobertura GPS, es necesario mejorar la fiabilidad en determinadas tecnologías clave para conseguir una operación robusta del sistema, tales como la localización, la evitación de obstáculos y la planificación de trayectorias. Actualmente, las técnicas existentes para la navegación autónoma de robots móviles en zonas sin GPS no son suficientemente fiables cuando se trata de robots aéreos, o no son robustas en el largo plazo. Esta tesis aborda el problema de la localización, proponiendo una metodología adecuada para robots aéreos que se mueven en un entorno tridimensional, utilizando para ello una combinación de medidas obtenidas a partir de varios sensores a bordo. Nos hemos centrado en la fusión de datos procedentes de tres tipos de sensores: imágenes y nubes de puntos adquiridas a partir de cámaras estéreo o de luz estructurada (RGB-D), medidas inerciales de una IMU (del inglés Inertial Measurement Unit) y distancias entre radiobalizas de tecnología UWB (del inglés Ultra Wide-Band) instaladas en el entorno y en la propia aeronave. La localización utiliza un mapa 3D del entorno, para el cual se presenta también un algoritmo de mapeado que explora las sinergias entre nubes de puntos y radiobalizas, con el fin de poder utilizar la metodología al completo en cualquier escenario dado. Las principales contribuciones de esta tesis doctoral se centran en una cuidadosa combinación de tecnologías para lograr una localización de UAVs en interiores válida para operaciones a largo plazo, de manera que sea robusta, fiable y eficiente computacionalmente. Este trabajo ha sido validado y demostrado durante los últimos cuatro años en el contexto de diferentes proyectos de investigación relacionados con la localización y estimación del estado de robots aéreos en zonas sin cobertura GPS. En particular en el proyecto European Robotics Challenges (EuRoC), en el que el autor participa en la competición entre las principales instituciones de investigación de Europa. Los resultados experimentales demuestran la viabilidad de la metodología completa, tanto en términos de precisión como en eficiencia computacional, probados a través de vuelos reales en interiores y siendo éstos validados con datos de un sistema de captura de movimiento.Unmanned Aerial Vehicles (UAVs) are currently used in countless civil and commercial applications, and the trend is rising. Outdoor obstacle-free operation based on Global Positioning System (GPS) can be generally assumed thanks to the availability of mature commercial products. However, some applications require their use in confined spaces or indoors, where GPS signals are not available. In order to allow for the safe introduction of autonomous aerial robots in GPS-denied areas, there is still a need for reliability in several key technologies to procure a robust operation, such as localization, obstacle avoidance and planning. Existing approaches for autonomous navigation in GPS-denied areas are not robust enough when it comes to aerial robots, or fail in long-term operation. This dissertation handles the localization problem, proposing a methodology suitable for aerial robots moving in a Three Dimensional (3D) environment using a combination of measurements from a variety of on-board sensors. We have focused on fusing three types of sensor data: images and 3D point clouds acquired from stereo or structured light cameras, inertial information from an on-board Inertial Measurement Unit (IMU), and distance measurements to several Ultra Wide-Band (UWB) radio beacons installed in the environment. The overall approach makes use of a 3D map of the environment, for which a mapping method that exploits the synergies between point clouds and radio-based sensing is also presented, in order to be able to use the whole methodology in any given scenario. The main contributions of this dissertation focus on a thoughtful combination of technologies in order to achieve robust, reliable and computationally efficient long-term localization of UAVs in indoor environments. This work has been validated and demonstrated for the past four years in the context of different research projects related to the localization and state estimation of aerial robots in GPS-denied areas. In particular the European Robotics Challenges (EuRoC) project, in which the author is participating in the competition among top research institutions in Europe. Experimental results demonstrate the feasibility of our full approach, both in accuracy and computational efficiency, which is tested through real indoor flights and validated with data from a motion capture system

    Ultrasonic wireless broadband communication system for underwater applications

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    Tese de doutoramento do Programa Doutoral em Engenharia Eletrónica e de ComputadoresUnderwater wireless communication systems are becoming a priority in terms of research and technological development due to the increasing demand for exploring the oceans’ potential in areas such as pharmaceutical, oil, minerals, environmental and biodiversity. This demand is increasing exponentially with the need for high data rate and near-real-time communications between submerged mobile and static agents. The existing wireless communication technologies using electromagnetic waves or lasers are not very efficient due to the large attenuation in aquatic environment. Ultrasound reveals a lower attenuation, and thus has been used in underwater long-distance communications. But the underwater acoustic medium is one of the less reliable communication channels which represent major challenges for communications. With relatively slow sound speed propagation (~1500 m/s) the delay may represent a problem for communications with real-time applications. A theoretical model of an underwater communication system was also developed. The model allows to emulate the emitter, the hydrophone and the underwater acoustic channel, which includes attenuation, environmental noise, Doppler Effect, multipath and propagation delay. This model supported the study of wireless communications by emulating the transmission of acoustic signals using different types of digital modulations. The acoustic signal attenuation, multipath, ambient noise in several environments theoretical results were compared to those obtained experimentally. Allowing to conclude that the model represents a suitable approximation to the real subaquatic communication channel for the evaluation of digital acoustic communications. An optimization study of ultrasound transducers for underwater communications was addressed, focusing on a piston type emitter operating in the thickness mode (d33). It was discussed how the acoustic impedance, thickness, resonance frequency and structure affect the transducer performance. This work allowed a better understanding of the emitter transducer characteristics allowing reaching the optimum point of operation for specific applications. Focusing on underwater communication, the transducer was optimized by finite element computer simulations. The results were compared with experimental tests and show that four-layer structures increase up to 16 dB in performance when compared to single-layer transducer disks. For high data-rates and real-time applications it was necessary to develop ultrasound transducers able to work at high frequencies and wideband, with suitable responses to digital modulations. It was thus also included a comparison study that shows how the acoustic impedance influences the performance of an ultrasonic emitter when using different digital modulations and operating at frequencies between 100 kHz and 1 MHz and some tens of meters of distance. It is presented a Finite Element Method (FEM) and a MATLAB/Simulink simulation with an experimental validation to evaluate two types of piezoelectric materials: one based in ceramics (high acoustic impedance) with a resonance design and a polymer based (low acoustic impedance) system, designed to optimize the performance when using digital modulations. The transducers performance for Binary Amplitude Shift Keying (BASK), On-Off Keying (OOK), Binary Phase Shift Keying (BPSK) and Binary Frequency Shift Keying (BFSK) modulations with a 1 MHz carrier at 125 kbps baud rate were compared. The transducers materials used were the ceramics PZT-5H and the polymer PVDF. The results show that PVDF transducer has a better performance to digital modulations than PZT-5H transducer, providing the signal full demodulation for all digital modulations tested. On the other hand, the PZT-5H transducer showed a higher output, but fails to perform accurate modulated signals. Finally, the system was validated by the implementation of a full duplex point-to-point communication at 1 Mbps using OOK modulation with a 1 MHz single carrier. The system was successfully tested in a swimming pool at a distance of 6 meters with a 1 Mbps rate, achieving a 3x10-3 Bit Error Rate (BER) using just 1.4 W of power consumption. These results represent an advance in underwater acoustic communications, being the first practical system to achieve data rates up to 1 Mbps.O desenvolvimento de sistemas de comunicação subaquáticos sem fios está a tornar-se uma prioridade na comunidade científica no sentido de aumentar o desenvolvimento tecnológico. Este facto deve-se à crescente necessidade de exploração do potencial dos oceanos em áreas científicas diversas como farmacêutica, petrolífera, mineral, ambiental e até do próprio estudo da biodiversidade. Essa necessidade aumenta exponencialmente com a necessidade de comunicações de alto débito e em tempo real entre agentes submersos móveis e estáticos. As tecnologias de comunicações sem fios existentes, nomeadamente as que utilizam ondas eletromagnéticas ou lasers não são muito eficientes, devido, em grande parte, à atenuação no ambiente subaquático. Os ultrassons revelam uma menor atenuação tendo sido, por isso, utilizados em comunicações subaquáticas em longas distâncias. Contudo o canal acústico subaquático definisse como um dos mais difíceis, devido em parte as suas características únicas, o que apresenta ser um enorme desafio. Como a velocidade de propagação do som é relativamente lenta (~1500 m/s), o atraso pode representar um problema para as aplicações em tempo real. Foi desenvolvido um modelo teórico do sistema de comunicações subaquáticos que permite emular o emissor, o hidrofone e o canal acústico subaquático. No canal acústico subaquático foi simulado o efeito da atenuação, ruído ambiente, efeito de Doppler, multipath e atraso de propagação. Este modelo é indicado para o estudo das comunicações subaquáticas, emulando a transmissão de sinais acústicos utilizando diferentes tipos de modulações digitais. Neste estudo foram testados, a atenuação do sinal acústico, multipath, ruído em diversos ambientes e os resultados teóricos foram comparados com os obtidos experimentalmente. Permitindo concluir que o modelo representa uma aproximação adequada do canal de comunicação, permitindo a avaliação das comunicações digitais acústicas. Inclui ainda um estudo de otimização de transdutores de ultrassons para comunicações subaquáticos, tendo como base o emissor do tipo pistão, operando ao longo da espessura (d33). Foi analisada ainda a forma como a impedância, espessura, frequência de ressonância acústica e estrutura afetam o desempenho do transdutor. Este trabalho permitiu uma melhor compreensão das características do transdutor emissor que permitem atingir o ponto ótimo de operação para aplicações específicas. Tendo como base a comunicação subaquática, o transdutor foi otimizado usando os resultados de simulações pelo Método dos Elementos Finitos. Os resultados foram comparados com os testes experimentais, onde se mostra que as estruturas de quatro camadas podem aumentar até 16dB no desempenho quando comparados com discos de transdutor de única camada. Para aplicações em tempo real e de elevado debito, foi necessário desenvolver transdutores de ultrassons capazes de operar em banda larga a altas frequências, com resposta adequada às modulações digitais. Foi, portanto, incluído também um estudo comparativo que mostra como a impedância acústica influencia o desempenho do emissor de ultrassons quando se utilizam modulações digitais a operar com frequências entre 100 kHz e 1 MHz abrangendo distâncias de algumas dezenas de metros. São apresentadas simulações por Método de Elementos Finitos (MEF) e MATLAB/Simulink com validação experimental de modo a avaliar dois tipos de materiais piezoelétricos: um com base cerâmica PZT-5H (alta impedância acústica) com um design de ressonância e outro de base de polimérica PVDF (baixa impedância acústica), otimizado para modulações digitais. O desempenho dos transdutores foi comparado para as modulações: Binary Amplitude Shift Keying (BASK), On-Off Keying (OOK), Binary Phase Shift Keying (BPSK) e Binary Frequency Shift Keying (BFSK) com uma portadora de 1 MHz a 125 kbps. Os resultados mostram que o transdutor de PVDF tem um melhor desempenho do que transdutor PZT-5H, proporcionando a desmodulação completa do sinal para todas as modulações digitais testadas. Por outro lado, o transdutor de PZT-5H mostrou uma potência acústica mais elevada, embora não consiga produzir sinais modulados precisos. Finalmente, o sistema foi validado através da implementação de uma comunicação ponto-aponto bidirecional de 1 Mbps utilizando uma modulação OOK com uma portadora de 1 MHz. O sistema foi testado com sucesso numa piscina a uma distância de 6 metros com uma taxa de 1 Mbps, com um BER (Bit Error Rate) de 3x10-3, utilizando apenas 1,4 W de consumo de potência. Estes resultados representam um avanço nas comunicações acústicas subaquáticas, sendo o primeiro sistema prático de atingir velocidades até 1 Mbps

    New Container Architectures for Mobile, Drone, and Cloud Computing

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    Containers are increasingly used across many different types of computing to isolate and control apps while efficiently sharing computing resources. By using lightweight operating system virtualization, they can provide apps with a virtual computing abstraction while imposing minimal hardware requirements and a small footprint. My thesis is that new container architectures can provide additional functionality, better resource utilization, and stronger security for mobile, drone, and cloud computing. To demonstrate this, we introduce three new container architectures that enable new mobile app migration functionality, a new notion of virtual drones and efficient utilization of drone hardware, and stronger security for cloud computing by protecting containers against untrusted operating systems. First, we introduce Flux to support multi-surface apps, apps that seamlessly run across multiple user devices, through app migration. Flux introduces two key mechanisms to overcome device heterogeneity and residual dependencies associated with app migration to enable app migration. Selective Record/Adaptive Replay to record just those device-agnostic app calls that lead to the generation of app-specific device-dependent state in services and replay them on the target. Checkpoint/Restore in Android (CRIA) to transition an app into a state in which device-specific information the app contains can be safely discarded before checkpointing and restoring the app within a containerized environment on the new device. Second, we introduce AnDrone, a drone-as-a-service solution that makes drones accessible in the cloud. AnDrone provides a drone virtualization architecture to leverage the fact that computational costs are cheap compared to the operational and energy costs of putting a drone in the air. This enables multiple virtual drones to run simultaneously on the same physical drone at very little additional cost. To enable multiple virtual drones to run in an isolated and secure manner, each virtual drone runs its own containerized operating system instance. AnDrone introduces a new device container architecture, providing virtual drones with secure access to a full range of drone hardware devices, including sensors such as cameras and geofenced flight control. Finally, we introduce BlackBox, a new container architecture that provides fine-grain protection of application data confidentiality and integrity without the need to trust the operating system. BlackBox introduces a container security monitor, a small trusted computing base that creates separate and independent physical address spaces for each container, such that there is no direct information flow from container to operating system or other container physical address spaces. Containerized apps do not need to be modified, can still make full use of operating system services via system calls, yet their CPU and memory state are isolated and protected from other containers and the operating system
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