The Internet of Things (IoT) is seen as one of the next Internet revolutions. In a near future the majority of all connected devices to the Internet will be IoT devices. These devices will connect previously offline constrained systems, thus it is essential to ensure end-to-end security for such devices. Object Security is a concept where the actual packet or sensitive parts of the packet are encrypted instead of the radio channel. A compromised node in the network will with this mechanism still have the data encrypted ensuring full end-to-end security. This paper proposes an architecture for using the object security format COSE in a typical constrained short-range radio based IoT platform. The IoT platform utilizes Bluetooth Low Energy and the Constrained Application Protocol for data transmission via a capillary gateway. A proof-of-concept implementation based on the architecture validates that the security solution is implementable. An overhead comparison between current channel security guidelines and the proposed object security solution results in a similar size for each data packet. The thesis concludes that object security should be seen as an alternative for ensuring end-to-end security for the Internet of Things.

Orientador: Alexandre César Rodrigues da Silva / Resumo: Transmissão de dados sem fio tem se tornado cada vez mais presente no dia a dia, devido a comodidade da não utilização de cabos, bem como pela maior mobilidade propiciada. Este trabalho aborda duas tecnologias de comunicação sem fio atuais: Identificação por Radiofrequência (RFID) e Bluetooth, destacando suas principais características e apresenta o protótipo de um circuito que efetua a leitura de tags fixadas em objetos, por meio de um leitor RFID e, posteriormente, transmite a identificação dessas a um smartphone, por meio da tecnologia Bluetooth. Com o propósito de ilustrar aplicações do protótipo construído, foram desenvolvidos dois softwares para smartphones Android: um de controle de medicamento de idosos e outro para auxiliar deficientes visuais nas aulas práticas laboratoriais. Durante o desenvolvimento do trabalho, testes foram realizados para se verificar o alcance de leitura do leitor RFID utilizado. Também foram realizados testes com a tecnologia Bluetooth, verificando-se a distância máxima de conexão e transmissão/recepção de dados entre o protótipo desenvolvido e um smartphone. / Abstract: Wireless data transmission has become increasingly present in everyday life, because the convenience of not using cables, as well as the greater mobility afforded. This paper addresses two current wireless communication technologies: Radio Frequency Identification (RFID) and Bluetooth, highlighting its main characteristics and presents the prototype of a circuit that performs the reading tags attached to objects by means of an RFID reader and later transmits the identification to such a smartphone, using Bluetooth technology. In order to illustrate prototype built applications, they developed two software for Android smartphones: one for the elderly medicine control and another to assist the visually impaired in the laboratory classes. During the development work, tests were conducted to verify the read range of the RFID reader used. Also with Bluetooth technology tests were performed, checking the maximum distance connection and transmission/reception of data between the developed prototype and a smartphone. / Mestre

Accurate indoor positioning of narrowband Internet-of-Things (IoT) sensors has drawn more attention in recent years. The introduction of Bluetooth Low Energy (BLE) technology is one of the latest developments of IoT and especially applicable for Ultra-Low Power (ULP) applications. BLE is an attractive technology for indoor positioning systems because of its low-cost deployment and reasonable accuracy. Efficient indoor positioning can be achieved by deducing the sensor position from the estimated signal Angle-of-Arrival (AoA) at multiple anchors. An anchor is a base station of known position and equipped with a narrowband multi-antenna array. However, the design and implementation of indoor positioning systems based on AoA measurements involve multiple challenges. The first part of this thesis mainly addresses the impact of hardware impairments on the accuracy of AoA measurements. In practice, the subspace-based algorithms such as Multiple Signal Classification (MUSIC) suffer from sensitivity to array calibration errors coming from hardware imperfections. A detailed experimental implementation is performed using a Software Defined Radio (SDR) platform to precisely evaluate the accuracy of AoA measurements. For this purpose, a new Over-the-Air (OTA) calibration method is proposed and the array calibration error is investigated. The experimental results are compared with the theoretical analysis. These results show that array calibration errors can cause some degrees of uncertainty in AoA estimation. Moreover, we propose iterative positioning algorithms based on AoA measurements for low capacity IoT sensors with high accuracy and fair computational complexity. Efficient positioning accuracy is obtained by iterating between the angle and position estimation steps. We first develop a Data-Aided Maximum a Posteriori (DA- MAP) estimator based on the preamble of the transmitted signal. DA-MAP estimator relies on the knowledge of the transmitted signal which makes it impractical for narrowband communications where the preamble is short. For this reason, a Non-Data- Aided Maximum a Posteriori (NDA-MAP) estimator is developed to improve the AoA accuracy. The iterative positioning algorithms are therefore classified as Data-Aided Iterative (DA-It) and Non-Data-Aided Iterative (NDA-It) depending on the knowledge of the transmitted signal that is used for estimation. Both numerical and experimental analyses are carried out to evaluate the performance of the proposed algorithms. The results show that DA-MAP and NDA-MAP estimators are more accurate than MUSIC. The results also show that DA-It comes very close to the performance of the optimal approach that directly estimates the position based on the observation of the received signal, known as Direct Position Estimation (DPE). Furthermore, the NDA-It algorithm significantly outperforms the DA-It because it can use a much higher number of samples; however, it needs more iterations to converge. In addition, we evaluate the computational savings achieved by the iterative schemes compared to DPE through a detailed complexity analysis. Finally, we investigate the performance degradation of the proposed iterative algorithms due to the impact of multipath and NLOS propagation in indoor environments. Therefore, we develop an enhanced iterative positioning algorithm with an anchor selection method in order to identify and exclude NLOS anchors. The numerical results show that applying the anchor selection strategy significantly improves the positioning accuracy in indoor environments. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished

This master's thesis deals with design of universal data logging device. The work proposes the design of device architecture and describes individual systems and components, that are necessary for data logging. Logger is designed as a mobile device, with ARM microcontroller at its core. Thesis specifies requirements for device in terms of performance and versatility. The device uses modular construction, as it comprises multiple PCBs. The thesis describes their design and also design of the mechanical construction of data logger. Designed device has been realized and assembled. Software design for microcontroller is also part of the thesis. In the last part, measurements to determine achieved parameters of the device are conducted.

Tato práce se zabývá návrhem demonstračního kitu bezlíčového přístupu pro vozidla s využitím nejnovějších integrovaných obvodů Bluetooth Low Energy a budičů automobilové sběrnice od společnosti ON Semiconductor. Aplikace umožňuje ruční i automatické odemykání dveří vozidla ze vzdáleného klíče realizovaného chytrým telefonem. Řešení se zabývá detekcí vzdálenosti vzdáleného klíče, bezpečností BLE spojení a komunikací přes automobilovou sběrnici LIN mezi moduly demonstračního kitu.

The object of this thesis is an analysis of the possibilities of a wireless communication and a sensor‘s equipment for a four legged walking robot. The thesis is divided into three parts. In the first part there is a particular sale’s exploration in the section of the wireless communication modules. It refers to the differences among technologies in the methods of signal transmission, the technical parameters but also in the communication protocols. The next part of this thesis is focused on sensor’s equipment with the accent on the possibility of use for a four legged walking robot. It contains a short listing of sensors, which are available in the Czech Republic with division based on the type of sensing magnitude. These two parts make a base for the last part where I have chosen suitable communication modules along with sensors and realization wireless data transfer including control and visualization. The result of this thesis is the complete communication block from the user to the robot.

This master thesis discusses design and realization of a security device for vehicles. This device can determine its actual location, discover unauthorized trespass and send information about this to a distant master system too. This distant master system can show the exact position of the security device on a map. The hardware and software for this security device and the software for the master system are described in this paper.

This thesis deals with the design and theoretical description of the hybrid control system for quadrocopter. First, a mathematical model is presented, sensors needed for development and their principles. This work shows the system architecture design and scheme of communication channels between the blocks. Implementation section discusses specific uses of computing nodes/sensors and their settings. In this thesis there are illustrated messages sent between computing nodes and the control loop machine. It also describes how to test the sensors, measurement results and techniques for improvement.

This master's thesis deals with the idea of using mobile devices as sensor nodes in wireless sensor network. Focused mostly on Android platform, we explore possibilities of wireless communication, and describe various types of sensors on mobile devices. We design and implement wireless sensor network based on mobile devices running Android operating system. The network performs real-time capturing of data from all sensors available and optionally from GPS. All measurements are visualized at the base station, which is Java Standard Edition desktop application. Wi-Fi, Bluetooth or even cellular internet can be used for communication within the network. Nodes can be remotely configured via SMS messages.

The main theme of this masters's thesis is to design and make a miniature universal tracking device. This device is primarily for tracking asset, pets or people. For detecting the position data is used GPS technology. Data transmission is carried out via the GSM network. The device is technically solved and realized with respect to miniature size, high battery life and with regard to resistance against water, dust and impact damage. It is selected unique design, suitable for hermeticaly closure of the entire facility. Due to hermetic closure there is any buttons, any connectors and the battery charging is wireless.