In this thesis, a system to locate an electrostatic discharge (ESD) event within an electronic device has been developed. ESD can cause a device to fail legally required radiated emissions limits as well as disrupt intended operation. The system used a fast oscilloscope with four channels, each channel attached to a high frequency near-field antenna. These antennas were placed at known locations in three dimensional space to measure the fields radiated from the ESD event. A Time-Difference-of-Arrival technique was used to calculate the location of the ESD event. Quick determination of the ESD event location provides developers with a tool that saves them time and money by eliminating the time-consuming and tedious method of general ESD mitigation within a product.

Today, positioning with GPS and the advantages this entails are almost infinitive, which means that the technology can be utilized in a variety of applications. Unfortunately, there exists a lot of limitations in conjunction with the signals from the GPS can’t reach inside e.g. buildings or underground. This means that an alternative solution that works indoors needs to be developed. The report presents the four most common radio-based technologies, Bluetooth,Wi-Fi, UWB and RFID, which can be used to determine a position. These all have different advantages in cost, accuracy and latency, which means that there exist a number of different applications. The radio-based methods use the measurement techniques, RSSI, TOA, TDOA, Cell-ID, PD or AOA to gather data. The choice of measurement technique is mainly dependent of which radio-based method being used, since their accuracy depends on the quality of the measurements and the size of the detection area, which means that all measurement techniques have different advantages and disadvantages. The measurement data is processed with one of the positioning methods, LS, NLS, ML, Cell-ID, WC or FP, to estimate a position. The choice of positioning method also depends on the quality of the measurements in combination with the size of the detection area. To evaluate the different radio-based methods together with measurement techniques and positioning methods, accuracy, latency and cost are being compared. This is used as the basis for the choice of positioning method, since a general solution can get summarized by finding the least expensive approach which can estimate an unknown position with sufficiently high accuracy.

The diploma thesis in theoretical part focuses on LPWAN in general, meaning the low power wireless device falling into IoT category with a focus on LoRaWAN. The second half of the theoretical part focuses on describing localization techniques and principles in general and selection of one suitable technique for implementation in LoRaWAN. The practical part focuses on the proper HW customizations to enable the localization in this network. There are also described all the steps needed to build the whole working LoRaWAN network. The TDoA localization algorithm is described, the functionality is verified by simulation and also by testing under real conditions. In the end, the results are explained, the shortcomings of the technology are described and finally a suggestion for improvement is provided.

This master thesis purposes is create localization system using software defined radio. The purpose of this thesis is to create new localization system, which will be independent of existing systems. To create a localization system, we will use ADALM-PLUTO device to send and receive radio signals. This work contains a decription of serval possibilities how to create the localization system and description of their comunication.

The aim of this term project was to analyze wireless indoor localization. It contains analysis of some wireless localization techniques such as Time of Arrival or Time Difference of Arrival. The paper also describes the system of SEWIO Company. Main part of the master’s thesis is description, design and implementation of the Kalman filter. The Kalman filter is used to improve two-dimensional positional data and synchronization of anchors (devices for finding a position of an object in SEWIO system). There are described a few system models for the Kalman filter.

Synchronization of distributed time difference of arrival (TDOA) sensor networks can be performed using reference signals from GPS satellites. This method provides high accuracy, but is vulnerable to jamming, and is not reliable enough to be used in military applications. A solution that does not depend on any signals transmitted from external actors is preferred. One way to achieve this is to use reference signals transmitted from a UAV. A UAV is suitable since only local synchronization for a geographically restricted area is necessary. The local synchronization is achieved by estimating the time-delay between the transmission and reception of a reference signal. The estimated time-delay can be used to detect drifts in the clocks of the TDOA sensors. This thesis analyzes com- mon reference signals, to evaluate which provide high accuracy for time-delay estimation, and what properties of the signals influence the estimation accuracy the most. The simulations show that the time-delay estimation performance can reach the same accuracy as synchronization against GPS for different types of signals. An increased bandwidth is more important than an increased signal length or signal-to-noise ratio to improve the estimation accuracy.

La vision future de l'internet des objets (IdO) et Internet du Tout (OIE) plongera les personnes soi-disant environnements intelligents impliquant un grand nombre de secteurs d'applications telles que l'habitat intelligent, smart-villes, surveillance de l'environnement, l'e-santé ... IdO et l'OIE ont tendance à faire des objets du quotidien lisible, identifiable, localisable, adressable et contrôlable via le déploiement sans fil généralisée et l'Internet. Parmi ces capacités, la localisation et plus largement le positionnement omniprésente joueront, dans un proche avenir, un rôle clé pour promouvoir une autre vision émergente: un Internet spatio-temporelle des lieux (IoP), qui serait en mesure de structurer et d'organiser, par des moyens des approches sans fil d'énergie savez, le contenu spatial d'Internet. Il est bien connu que dans les réseaux locaux sans fil et personnelles, l'encombrement du spectre, les communications à faible efficacité énergétique et l'exploitation insuffisante des ressources spatiales sont parmi les facteurs qui peuvent ralentir son développement en termes de débit et de l'autonomie. Pour surmonter ces restrictions inévitables, la technologie de localisation sans fil, comme le mécanisme pour découvrir relation spatio-temporelle entre les objets connectés, apparaît ici aussi comme une des solutions clés. Ce est parce que les techniques de localisation dédiés à la communication sans fil peuvent aider à développer plus largement l'exploitation des ressources spatiales et de permettre la conduite routage optimisé pour une faible énergie communication multi-hop et la décongestion du spectre pour Green ICT (Information et Communication Technology). Pour proposer des systèmes optimisés atteindre à la fois la communication des taux de données élevés et la localisation précise, nous définissons un TDOA bien adapté (Time Difference of Arrival) méthode basée en mesure d'effectuer la localisation basée sur des signaux de communication et de données seulement. Avec cette technique, contrairement estimations TDOA classiques, il est possible de diminuer considérablement la complexité des infrastructures nécessaires en utilisant des configurations SIMO (Single Input Multiple Output), MISO (Multiple Input Single Output) ou MIMO (Multiple Input Multiple Output) dans les objets connectés . Toute cette étude est faite dans le cadre de l'IEEE 802.11ad spécifications de l'alliance standard et WiGig, mais les solutions proposées sont compatibles avec d'autres normes et peuvent être étendues à d'autres applications de contexte courant nécessitant entrées de localisation tels que la robotique par exemple ou de shopping intelligent... / The forthcoming vision of Internet of Things (IoT) and Internet of Everything (IoE) will immerse people in so-called Smart Environments involving a great number of sectors of applications such as smart habitat, smart-cities, environment monitoring, e-health… IoT and IoE tend to make everyday objects readable, recognizable, locatable, addressable and controllable via the widespread wireless deployment and the internet. Among these capabilities, localization and more extensively the ubiquitous positioning will play, in the next future, a key role to promote another emerging vision: a spatio-temporal Internet of Places (IoP), which would be able to structure and organize, by means of wireless energy aware approaches, the spatial content of Internet. It is well known that in wireless local and personal area networks, the spectrum congestion, the low energy efficiency communications and the insufficient exploitation of the spatial resources are among the factors that may slow down its development in terms of throughput and autonomy. To overcome these unavoidable restrictions, wireless localization technology, as the mechanism for discovering spatio-temporal relationship between connected objects, appears here also as one of the key solutions. This is because dedicated localization techniques in wireless communication can help in developing more extensively the exploitation of spatial resources and allow driving optimized routing for low energy multi-hop communication and spectrum decongestion for Green ICT (Information and Communication Technology). To propose optimized systems achieving both high data rate communication and precise localization, we define a well suited TDOA (Time Difference of Arrival) based method able to perform localization based on communication signals and data only. With this technique, unlike conventional TDOA estimations, it is possible to drastically decrease the complexity of required infrastructures by using either SIMO (Single Input Multiple Output), MISO (Multiple Input Single Output) or MIMO (Multiple Input Multiple Output) configurations in connected objects. This whole study is made within the framework of the IEEE 802.11ad standard and WiGig alliance specifications, however the proposed solutions are compatible with other standards and can be extended to other context aware applications requiring localization inputs such as robotics for example or smart shopping...

There are a lot of stand-alone and mobile platforms using transmitters today. Some want to be found while others do not. In our modern society there is a great demand of mobility and communication abilities. This means that several mobile platforms could potentially carry a sensor to record incoming signals to be used in Direction Finding. This thesis identifies the possibility to determine the direction to a transmitter with randomly placed sensors. By conducting a literature review well-known methods such as Time Difference Of Arrival (TDOA) and MUltiple SIgnal Classification (MUSIC) where chosen as methods in this analysis. The methods are applied on two antenna arrays, an Uniform Circular Array (UCA) and a Random Circular Array (RCA). The RCA is generated with randomly placed sensors. The performance in the Direction Of Arrival (DOA) is investigated in presence of time synchronization error and with different numbers of elements, radius and Signal to Noise Ratio (SNR). The ambiguity in the arrays is also investigated to insure a ambiguity-free DOA estimation. The results from this analysis identifies that the accuracy in the DOA estimation is dependent on the number of elements, SNR, the elements positions and the radius of the DF array. Furthermore, the accuracy of a UCA is greater than a RCA when the elements are randomly distributed within the area of a circle with radius R. Finally, it has shown that if time synchronization error occurs between the sensors, then the MUSIC method the accuracy will decrease greatly. / Det finns många individer och mobila platformar som använder sändare idag. Vissa vill bli hittade, andra inte. I vårat moderna samhälle är det en stor efterfrågan på rörlighet och kommunikationsmöjligheter. Detta innebär att många mobila plattformar skulle kunna spela in signaler för att användas i radiopejling. Denna uppsats identifierar möjligheten att bestämma riktningen till en sändare med slumpmässigt placerade sensorer. Genom litteraturstudien identifierades de välkända riktningsmetoder som Time Difference Of Arrivial (TDOA) och MUltiple SIgnal Classification (MUSIC) som vidare valdes som metoder i denna analys. Två antennstrukturer används i analyserna. Den ena är en Uniform Circular Array (UCA) och den andra är en Random Circular Array (RCA). RCA är genererad med slumpmässigt utplacerade sensorer. Prestandan i riktningsuppskattningen undersöks när det existerar ett tidssynkroniseringsfel, olika antal sensorer i antennstrukturerna, varierande radier och olika signaloch brusförhållanden.Ä ventvetydigheter undersöks i strukturerna för att säkerställa att en entydig riktningsbestämning kan utföras. Resultaten implicerar att noggrannheten i riktningsbestämningen är beroende avantalet element, SNR, elementens position och radien i antennmatrisen. Utöver detta visar resultaten att en UCA har högre noggrannhet än en RCA då elementen är slumpmässigt utplacerade inom en cirkelradie, R. Slutligen, om tidssynkroniseringsfel uppstår mellan sensorerna kommer detta resultera i minskad noggrannhet när MUSIC metoden tillämpas.

The Global Positioning System (GPS) provides good precision on a global scale, but is not suitable for indoor applications. Indoor positioning systems (IPS) aim to provide high precision position information in an indoor environment. IPS has huge market opportunity with a growing number of commercial and consumer applications especially as Internet of Things (IoT) develops. This paper studies an IPS approach using audible sound and pseudo-noise (PN) based time difference of arrival (TDoA). The system’s infrastructure consists of synchronized speakers. The object to be located, or receiver, extracts TDoA information and uses multilateration to calculate its position. The proposed IPS utilizes sound waves since they travel much slower compared to electromagnetic waves, allowing for easier measurements. Additionally, the audible spectrum has a large availability of low directivity speakers and microphones allowing for a large coverage area compared to highly directive ultrasonic transceivers. This paper experimentally evaluates the feasibility of the proposed IPS.

A low-cost radio direction finding (RDF) VHF receiver has been investigated for development into a radio direction finding network (RDFN) with a particular focus towards public service and commercial asset tracking applications. The primary design criteria were reproducibility, low-cost, and simplicity such that public service and volunteer organizations can benefit from the technology. Two receiver designs were built and tested to allow for comparison of practicality, cost, and accuracy. A pseudo-Doppler RDF and a time difference of arrival (TDOA) receiver were built as proof-of-concept for a system design based on commercial off-the-shelf (COTS) components. The pseudo-Doppler system is a less practical implementation due to the necessity for custom hardware, a large antenna system, and an increased directional error due to multipath and weak signals. The TDOA system has potential as a very simple and low-cost RDFN implementation, but requires extremely accurate time synchronization that is difficult to achieve using COTS GPS receiver modules. The final proposed solution takes advantage of the simple TDOA hardware and multiple detection techniques (including signal strength) to produce improved locational data and ultimately provide a more accurate estimate of position. Further development and improvements to this receiver design have the potential for implementation as a low-cost radio direction finding network.