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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.
31

An experimental investigation of a crossover concept for high accuracy indoor positioning systems

Lind, Andreas January 2015 (has links)
To know your whereabouts is important and sometimes exact position is the determinant of success or not. Since the launch of the USA made Global Positioning System (GPS) in the late 1970s, global tracking has been available both for military and civilian use. Today, satellite based systems like the American GPS, European Galileo and the Russian GLONASS are the standard for basically any navigation or location application. However these systems are limited by the fact that they must have connection with multiple satellites in order to work. This means that satellite dependent systems are very limited in indoor environments. Despite this, there is no standard for indoor positioning systems (IPSs) even close to the satellite dependent systems when it regards distribution and accessibility for use where satellite dependent systems are limited or not working. However, this new age of connectivity provides a number of options for positioning indoors. There are some systems available, but very few of them provide good enough accuracy. This Master thesis evaluates different options for indoor positioning using technologies that are available in smart devices and smart phones, such as Wi-Fi and Bluetooth, and focuses on indoor positioning systems that can provide high accuracy. The current state of the technologies and the possible future for them, considering rising need and interest in indoor positioning systems are covered in this thesis. A selection of technologies and approaches are explored, tested in conditions designed for this purpose and evaluated to highlight their differences in approach, accuracy and usability. In order to achieve the goals of this thesis, a hybrid method of experimental research design and system development is selected as the main research method. The hybrid method is focused on experimental research, and is used to investigate if the accuracy of the positioning data can be affected and improved by tuning independent variables in an IPS. To be able to do this, an application for smart devices, such as android smartphones, is developed. The application developed is the heart of the conceptual crossover IPS (CCIPS), which is named Locantis, that is being developed and used in the experimental stages of this investigation. It is also used to test the hypothesis that a CCIPS could be a valid contender for replacing the established IPSs. The observations show how the accuracy and precision of the location data is affected by change to independent variables in an IPS and how well a CCIPS can meet real time requirement’s. The main conclusion is that changes to independent variables have greater impact on the precision than the accuracy for location data in an IPS and that a CCIPS in many cases are the sensible choice of IPS. / Att veta var du befinner dig är viktigt och ibland är exakt position avgörande för framgång. Sedan lanseringen av amerikanska Global Positioning System (GPS) i slutet av 1970 har global navigation varit tillgängliga för både militärt och civilt bruk. Idag är satellitbaserade system, som det amerikanska GPS, europeiska Galileo och det ryska GLONASS, standard för i princip alla navigering eller platsinformation. Men dessa system är begränsade av det faktum att de måste ha kontakt med flera satelliter för att fungera. Detta innebär att satellitberoende system är mycket begränsad i inomhusmiljöer. Trots detta finns det ingen standard för inomhus positioneringssystem (IPSS) som kan mäta sig med de satellitberoende systemen när det gäller distribution och tillgänglighet. Men denna nya generationens kommunikation ger ett antal alternativ för positionering inomhus. Det finns IPS tillgängliga idag, men väldigt få av dem kan tillhandahålla en hög noggrannhet på positioneringen. Detta examensarbete utvärderar olika alternativ för inomhuspositionering med teknologier som är tillgängliga i smarta enheter och smarta telefoner, som Wi-Fi och Bluetooth, fokus ligger på inomhus positioneringssystem som kan ge hög noggrannhet. Det aktuella läget för dessa teknologier och dess möjliga framtid, med tanke på stigande behov och intresse av inomhus positioneringssystem, behandlas i detta examensarbete. Ett urval av teknologier och metoder utforskas, testas under förhållanden utformade för detta ändamål, och utvärderas för att lyfta fram sina skillnader i tillvägagångssätt, noggrannhet och användbarhet. För att uppnå målen i detta examensarbete har en hybrid metod för experimentell designforskning och systemutveckling valts som huvudsaklig forskningsmetod. Hybridmetoden fokuserar på experimentell forskning och används för att undersöka om positioneringsdatas noggrannhet kan påverkas och förbättras genom att förändra oberoende variabler i ett IPS. För att kunna göra detta har en applikation för smarta enheter, så som Android, utvecklats. Applikationen som utvecklats är hjärtat i det konceptuella kombinations inomhuspositioneringssystem Locantis som utvecklas och används i det experimentella stadiet i denna undersökning. Den används också för att testa hypotesen att en CCIPS kunde vara en giltig kandidat för att ersätta den etablerade IPSer. Observationerna visa hur noggrannhet och precision av positioneringsdata påverkas av förändring på oberoende variabler i ett IPS och hur väl ett CCIPS kan uppfylla realtidskravet talet. Huvudslutsatsen är att förändringar på oberoende variabler har större inverkan på precision än noggrannheten för lokaliseringsuppgifter i en IPS och att ett CCIPS i många fall är det klokt val av IPS.
32

Evaluation of Different Radio-Based Indoor Positioning Methods

Ahlberg, Sven January 2014 (has links)
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.
33

Indoor Mobile Positioning system (MPS) classification in different wireless technology domain

Ghandchi, Bahram, Saleh, Taha January 2018 (has links)
The main purpose of this thesis work is to find and compare different network characteristics of MPS (Mobile Positioning System) in the different wireless technology domains. Since decades ago MNO’s (Mobile Network Operators) added many new services based on the geographical areas of subscribers and their needs. Here we define wireless networks and go through different types of technologies and do the comparison when they collect different types of data for their location-based services and see if we could have the same accuracy with 2G (second generation) of mobile network as like as 3G (third generation) and higher. Finally, we will come up with a proposal for new age technology.
34

Inomhuspositionering med tre olika tekniker – Bluetooth Low Energy, Wi-Fi och GPS : En jämförelsestudie av positioneringsverktyg vid inomhuspositionering / A comparison study of positioning tools in indoor positioning

Rasch, Kevin, Lipponen, Dennis January 2018 (has links)
Olika navigeringstekniker är något som människan använder sig av dagligen. Det är och har varit en viktig del genom tiderna, i början handlade det om att kunna navigera till havs med hjälp av stjärnorna och idag har många människor i världen någon form av smarttelefon som kan användas som navigeringsverktyg. Inomhuspositionering är något som har blivit ett hett ämne den senaste tiden och eftersom GPS fungerar sämre inomhus har nya tekniker utvecklats för att navigera och positionera sig inomhus. De tekniker som ligger i framkant nu är bland annat Bluetooth Low Energy (BLE) och Wi-Fi där man med hjälp av triangulering kan positionera ut en användare inomhus. Frågan återstår då, vilket positioneringsverktyg är då lämpligt för inomhuspositionering. Detta examensarbete har utförts med en kombination av strategier. Som börjar med en jämförelsestudie av tre olika positioneringstekniker, BLE Wi-Fi och GPS, för att ta fram en lämplig positioneringsteknik för utvärdering i form av ett experiment där flera faktorer, främst precisionen, testas. I denna studie användes BLE beacons som positioneringsverktyg dels för att den var lätt att implementera men även för att den skulle uppnå hög precision. För att testa BLE beacon utvecklades en lätt applikationsprototyp som hade som huvudsyfte att kunna positionera ut en användare i ett koordinatsystem med hjälp av XYvärden. Genom att triangulering användes för att kunna positionera ut en användare uppnådde studien en medelmarginal på ungefär 76 centimeter när fem stycken beacons användes i ett område på 4 x 3 meter, vilket vi ansåg som godkänt för att kunna dra slutsatsen att BLE beacon är ett lämpligt verktyg när det kommer till en inomhuspositionering. Slutsatsen blev även att det skiljer sig avsevärt mycket i precision om man använder sig av för få eller helt enkelt dåligt placerade beacons. / Different navigation techniques are something that people uses on a daily basis. It has been and still is an important part in the history of mankind, initially navigation was about being able to navigate at sea using the stars, and today many people around the world have some kind of smartphone that can be used as a navigation tool. Indoor positioning is something that has become a hot topic in the last decade and since GPS has bad precision indoors new technologies has been developed to navigate and position objects indoors. Some leading technologies now includes Bluetooth Low Energy beacons and Wi-Fi, where you can position a user indoors using triangulation-techniques. The question still remains, which technique is viable for indoor positioning. This study has been conducted as a combination of two strategies, starting with a comparison study of three different positioning techniques, BLE, Wi-Fi and GPS, to come to a conclusion which positioning technique is suitable for indoor positioning. After the conclusion we evaluated the technique in the form of an experiment in which several factors, mainly the precision, are tested. In this study, BLE beacon were used as the positioning tool because it was easy to implement but also to able to achieve high precision in the right environment. To test the beacons, a light application prototype was developed that had the main purpose of positioning a user in a coordinate system using XY values. By using triangulation to position the user. The study achieved a mean margin of approximately 76 centimeters when five beacons were used in a 4 x 3 meter area. The conclusion was BLE beacons is a suitable tool when it comes to indoor positioning and that there is a lot of difference in precision when using too few or poorly placed beacons.
35

Técnica de localização em ambientes fechados utilizando padrões de redes sem fio. / Indoor location technique with wireless fingerprint.

Lucas Juliano Spinola Costa 05 December 2014 (has links)
Localizar objetos ou pessoas no interior de um edifício é de grande interesse. Contudo, diferentemente do que ocorre no exterior de edificações, não há metodologia consagrada para a determinação da posição desses entes nos edifícios. Para o posicionamento em locais abertos existem tecnologias consolidadas, como GNSS (Global Navigation Satellite System), a dificuldade em fazê-lo em interiores é maior. Nesses casos, o GNSS não pode ser utilizado, pois os sinais de rádio dos satélites não conseguem penetrar através das estruturas, enquanto que outras tecnologias são apenas incipientes nesse quesito. Abordagens habituais para a resolução dessa demanda têm se baseado na utilização de propagadores das ondas de rádio do GNSS, no uso da potência de sinais de redes sem fio ou, ainda, no emprego de transmissores infravermelhos. No entanto, uma técnica diferente pode ser empreendida para essa finalidade. Usando-se a assinatura das potências de rádio das redes sem fio nas imediações e no interior da edificação, é possível criar um mapa com base nesses sinais, permitindo a determinação da posição de um objeto. No presente trabalho foram desenvolvidos um sistema para geração do mapa de sinais, com critério de parada e um método de cálculo de posicionamento. Procedeu-se, também, à análise de quatro critérios para o cálculo final da posição do objeto, baseados no uso da distância euclidiana com os conjuntos de roteadores disponíveis. Concluiu-se que, quando o mapa de sinais é pequeno, o posicionamento fracassou. Entretanto, quando a quantidade de sinais geradores do mapa aumenta, os resultados apresentaram melhora significativa, com resultados próximos a 100% de assertividade. Desse modo foi possível determinar uma estimativa boa para o número mínimo de roteadores presentes na base e estabelecer um critério de parada para a fase de criação do mapa de sinais. / Locate objects or person inside a building is a subject that matters. Although what occurs outdoor of a building, there is no consolidate methodology to define a position in an indoor environment. For outdoor positioning there is the GNSS (Global Navigation Satellite System) a consolidate technology for outdoor usage with a lot of challenges to make this work in an indoor environment. In such cases, the GNSS cannot be used due to the lack of the sattelite radio signal, which cannot penetrate the walls and buildings structures, meanwhile other technologies are just incipient. Usual approaches using this approach are based in propagation of the GNSS radio signal, wi-fi based location or infrared transmitter. A different technique can be applied for indoor positioning. Using the wireless fingerprint in an indoor environment we created a radio map based on those signals, allowing the location of a mobile station. In the present research, we developed a system that generates a radio map (with a stop criteria) and a positioning calculation method. We concluded that when the radio map is small (with only a few measurements) the method cannot calculate accurately. However, with more measurements, the method succeeded and have a performance near a 100% of precision. In this way it was posible to estimate a number of access points needed for a building\'s range and define the stop criteria used in the radio map phase.
36

An indoor positioning system using multiple methods and tools

Sehloho, Nobaene Elizabeth January 2015 (has links)
Thesis (MTech (Information Technology))--Cape Peninsula University of Technology, 2015. / Recently, the deployment and availability of wireless technology have led to the development of location and positioning services. These Location Based Services (LBSs) are attracting the attention of researchers and mobile service providers. With the importance of ubiquitous computing, the main challenge seen in the LBS is in the mobile positioning or localization within reasonable and certain accuracy. The Global Positioning System (GPS), as a widely known and used navigation system, is only appropriate for use in outdoor environments, due to the lack of line-of-sight (LOS) in satellite signals that they cannot be used accurately inside buildings and premises. Apart from GPS, Wi-Fi is among others, a widely used technology as it is an already existing infrastructure in most places. This work proposes and presents an indoor positioning system. As opposed to an Ad-hoc Positioning System (APS), it uses a Wireless Mesh Network (WMN). The system makes use of an already existing Wi-Fi infrastructure. Moreover, the approach tests the positioning of a node with its neighbours in a mesh network using multi-hopping functionality. The positioning measurements used were the ICMP echo requests, RSSI and RTS/CTS requests and responses. The positioning method used was the trilateral technique, in combination with the idea of the fingerprinting method. Through research and experimentation, this study developed a system which shows potential as a positioning system with an error of about 2 m – 3 m. The hybridization of the methods proves an enhancement in the system though improvements are still required
37

Real-time detection of attendance at a venue using mobile devices

Sagboze, Konzi Olivier January 2017 (has links)
Thesis (MTech (Information Technology))--Cape Peninsula University of Technology, 2017. / The implosion of the mobile phones, mobile applications and social media in recent years has triggered a great interest for more dedicated user-generated contents. Mobile users being the focal point, these modern virtual platforms depend on and live for collecting, structuring and manipulating the very fine-grained details about users' day-to-day activities. Since every human activity takes place in a geographical context, location information ranks high among the set of data to gather about user's daily life. User's specific location details can help filter content to serve and retrieve from them. Therefore, location-based services have been developed and successfully integrated into most virtual platforms in the quest for these precious data. However, location-based services do not fulfil all requirements. They depend on a range of positioning systems which show numerous limitations. None of the existing positioning systems is perfectly accurate. Today, it is therefore difficult to pinpoint a user in a venue using location-based services. Nevertheless, with the set of existing technology and techniques, it is possible to estimate and track users’ whereabouts in real-time. Providing the best possible estimation of user's position within a given venue can help achieve better user engagement. Depending on the gap of accuracy, the end result may actually match the outcome expected from perfectly accurate positioning systems. In this work, the focus is to develop a prototype positioning system which provides the best estimation of user's position in real-time in relation to a targeted venue or location. Through a series of research and comparison study, the most suited technology and techniques are objectively selected to build the intended prototype. The challenge of indoor positioning is also addressed in this work – bearing in mind the fact that this prototype is set to work accurately and efficiently in any geographical location and structure. The prototype is evaluated according to a set of predefined standard metrics, and theories are extracted to grow knowledge about this trending topic.
38

Research and implementation of an indoor positioning algorithm

Liu, Honggang January 2017 (has links)
The goal of the Internet of Things’ sensing technology is to provide LBS(location-based services); a key technology is finding out how to positioning the sensing devices. For positioning outdoors, mature tech-nology such as GPS and cellular network location can be used. There is little research about indoor positioning, and there is no finished product on the market. This paper shows how to use both Wi-Fi and ZigBee signal for position-ing; Wi-Fi to find the area position and ZigBee to find the coordinate position. The main contribution of this paper is described in the follow-ing: This paper will present an algorithm using kNN on a Wi-Fi signal, as a way to find the location area of users. The GPS signal cannot be used indoors, but there are usually numerous Wi-Fi signals, that can be used for indoor positioning. In this design, to build a dataset containing the number of locations and the Wi-Fi signal strength list of each location. When indoor positioning is needed, the KNN algorithm is used to compare the user’s Wi-Fi signal strength with the dataset and find the location number. When precise positioning is needed, the ZigBee signal should be used. In this paper two different methods for precise positioning in are used, one is an improved algorithm of triangle centroid algorithm where the positioning accuracy depends on the number of anchor points and the interval of each point. The other method is the neural network method. This method could give stable result with only four anchor points. Finally, there is a comparison of the methods mentioned in this paper : the Wi-Fi fingerprint method, the ZigBee triangle centroid algorithm, and neural network method.
39

Algoritm för lokalisering av referensnoder med Indoor Positioning System

Abbassi, Selma, Engström, Rickard January 2016 (has links)
Indoor Positioning Systems lokaliserar människor och objekt inomhus med hjälp av minst tre kända referenspunkter. System för inomhuspositionering som använder kända referenspunkter kallas anchor-based lokalisering medan de som beräknar deras positioner själva kallas anchor-free lokalisering. Syftet med detta arbete är att utveckla en algoritm som är anpassad efter ett anchor-free lokaliseringssystem. Den ska vara oberoende av nätverksuppkopplingen, hårdvaran och hur avstånden mellan mottagare och sensorer beräknats. Utgångspunkten för algoritmen är enbart avstånd mellan en mottagare och tre sensorer vilket kan beskrivas som arbetets huvudsakliga problem. Algoritmen implementerades i Java med en simulering som återspeglar positioneringen i en perfekt miljö och sedan testas på en Android-applikation. Simuleringen tillåter användaren att rita ut flera mätpunkter som skapar en rutt. Dessa mätpunkter utnyttjas för att dynamiskt lokalisera referenspunkterna och mätpunkterna genom att hitta ett minsta avstånd mellan sensorerna. Dessa avstånd kan beskrivas som sidorna för en referenstriangel som möjliggör att ett koordinatsystem kan spännas upp. Resultatet av den empiriska studien visade en felmarginal mellan 0,3-6 m utan signalstörningar, vilket inte var tillräckligt noggrant. Efter att algoritmen implementerats lades fokus på en korrigering som kan itereras igenom för att uppskatta bättre mätvärden för referenstriangeln. Korrigeringen gav positiva resultat med lägre felmarginal. Arbetet kan vidareutvecklas genom att implementeras i ett verkligt IPS-system och algoritmen kan förbättras genom att skapa utökade funktioner som kan hantera fler än tre beacons.
40

Radiobaserad spårning av rörlig utrustning inomhus

Davodi, Rashed, Högberg, Jonatan January 2017 (has links)
No description available.

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