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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.
51

Indoor positioning utilizing Bluetooth Smart : A comparative study between trilateration and fingerprinting / Inomhuspositionering med Bluetooth Smart

Nygård, Niklas January 2015 (has links)
This thesis explores the possibilities of constructing an indoor positioning system based on Bluetooth Smart technology. Two non-trainable trilateration approaches and two trainable fingerprinting were implemented and evaluated at Mobiento's offices in Stockholm, Sweden. A trilateration approach is based on finding a sought location based on known distances towards know locations, at least three locations and distances are needed. A fingerprinting approach is based on creating a radio map, which describes transmission signals within the room, towards different transmitters. A set amount of coordinates are assigned a fingerprint. These are then used as reference points for a sought location. For each major approach, trilateration and fingerprinting, a weighted approach is conducted. These approaches are evaluated in a disturbance free environment in term of accuracy, implementation and setup. In terms of accuracy, the non-weighted fingerprinting approach performs slightly better than the weighted fingerprinting approaches. Both of these are more accurate than the trilateration approaches. When it comes to implementation and setup, the trilateration algorithms impose less cost. These allow for better scalability when the indoor environment becomes larger.
52

Entwicklung und Untersuchung eines Konzepts zur Nutzung von Indoor-Positioning-Technologie in Systemen für adaptive, mobile Informationsbereitstellung

Ludyga, Tomasz 17 January 2022 (has links)
Die dynamische Entwicklung mobiler Systeme macht es erforderlich, adaptive Informationen auf der Grundlage der Position von Objekten bereitzustellen. Im Anwendungsgebiet der Indoor Positioning, bei dem die Signale des globalen Navigationssatellitensystems nicht erreichbar sind, existiert bisher keine Standardlösung für die optimale Umsetzung. Im Rahmen dieser Arbeit wird die Umsetzung anhand von realen und abstrakten Systemen für die adaptive und mobile Bereitstellung von Informationen analysiert und in Bezug auf den medizinischen Bereich vertieft. Dementsprechend wird die Integration mehrerer Positionierungsverfahren in ein System zur Nutzung von Smart Glasses implementiert. Der Entwurf- und Implementierungsprozess basiert auf einer Analyse aktueller Lösungen und Methoden. Abschließend ist das Konzept mit Hilfe einer Anforderungsanalyse, einer Evaluationsstrategie und einer Simulationsumgebung untersucht worden.:1. Einleitung 1 2. Adaptive, mobile Informationsbereitstellung 5 3. Indoor Positioning 10 4. Analyse 18 5. Design und Realisierung 25 6. Evaluation 33 7. Diskussion und Fazit 36
53

Using BLE mesh network for indoor tracking

Hassan, Ali, Ahlquist, Anna January 2019 (has links)
Internet of Things ger människor möjligheter att genom tjänster dra nytta av sensorer och andra enheter som tillsammans skapar ett brett utbud av lösningar som smart hem, smart transport, äldreomsorg och mycket mer. Den senaste innovationen av Bluetooth SIG är Bluetooth mesh topologi som tillåter att ansluta trådlösa enheter i ett många till många förhållanden. I denna avhandling utvecklade vi ett inomhusspårningssystem baserat på Bluetooth Low Energy teknik och mesh topologi för att undersöka de potentiella fördelar som Bluetooth Low Energy nätverk har att erbjuda för inomhusspårningssystemet. Systemet är utvecklat för att spåra Bluetooth beacon i en inomhus kontorsmiljö. Received Signal Strength används för att beräkna avståndet till beacon, medan positionen av beacon beräknas med Extended Min-Max och Trilateration algoritmer. Beräkningar utförs på servern. Resultaten analyseras genom jämförelse av Root Mean Square Error av båda algoritmerna. I denna avhandling utvärderas inomhusspårning som en del av ett uppdrag som ges av u-blox. / The Internet of Things brings connectivity of people, services, sensors and other devicesenabling a wide range of applications like smart home, smart transport, elder care andmuch more. The latest innovation of Bluetooth SIG is the Bluetooth mesh topology thatallows us to connect wireless devices in a many-to-many relationship. To investigate thepotential benefit that the BLE mesh network has to offer for the indoor tracking system.In this thesis, we developed an indoor tracking system based on Bluetooth Low Energytechnology and mesh topology. The system is developed to track Bluetooth beacon inan indoor office environment. Received Signal Strength is used to calculate the distance tothe beacon, while the position of the beacon is calculated using Extended Min-Max andTrilateration algorithms. Calculations are performed on the server. The results are analysed through comparison of Root Mean Square Error of both algorithms. In this thesis, indoor tracking is evaluated as part of an assignment given by u-blox.
54

A Multi-User Coordination Scheme for LTE Indoor Positioning System

Vemuri, Krishna Karthik January 2020 (has links)
No description available.
55

Virtual alignment of real-world objects

Ekberg, Tommy, Ekelund, William January 2023 (has links)
High accuracy localization of objects is a crucial function for many modern applications, such as virtual and augmented reality, robotics, and self-driving cars, among others. This requires determining precise location of objects indoors, which is a challenging task. In recent years, Ultra-Wideband technology has seen increasing interest as a potential solution to this problem by the research community. This is mainly due to its innate capabilities of high update frequency and low power consumption which makes it a suitable technology for precise distance measurement and location determination. This study has aimed to answer what the state-of-the-art in the field of trilateration in Ultra-Wideband based indoor positioning systems utilizing other complementary technologies is. This was done by conducting a document survey using a Grounded theory approach for the analysis. To ensure validity and reliability of the study, the sample was collected through searching IEEE Xplore using different sets of keywords, and the potential samples was then checked using a data quality form. The analysis consisted of identifying categories and concepts in the sample. The analysis found that the Ultra-wideband based systems can achieve high positioning accuracy, but limitations such as non-line-of-sight disturbance must still be overcome for the technology to consistently achieve centimetre accuracy. These limitations are being mitigated using filtering, machine learning, and multi-sensory fusion. With these complementary technologies researchers can eliminate some of the limitations. The field does however seem to be in an exploratory stage where best practices for overcoming the current limitations are yet established.
56

Indoor Positioning Using Acoustic Pseudo-Noise Based Time Difference of Arrival

Luong, Nicholas J 01 June 2020 (has links) (PDF)
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.
57

Distance Estimation Using Ofdm Signals for Ultrasonic Positioning

Huang, Kyman 01 June 2020 (has links) (PDF)
This paper describes a method of estimating distance via Time-of-Flight (TOF) measurement using ultrasonic Orthogonal Frequency Division Multiplexing (OFDM) signals. Using OFDM signals allows the signals and their sub-carriers to remain orthogonal to each other while continuously transmitting. This estimation method is based on the change of phase of a traveling wave as it propagates through a medium (air for ultrasonic signals). By using signals containing multiple tones, the phase change between each frequency component is slightly different. This phase difference is dependent on the distance traveled and can thus be used to estimate distance. This paper studies the impact of tone (OFDM sub-carriers) separation on accuracy, maximum distance, and computation for two-tone and three-tone systems. The effects of the transducer channel bandwidth and channel noise are accounted for to build an accurate model for a single-transmitter single-receiver system. This study found that each additional tone provides one extra independent distance measurement which improves accuracy in the presence of noise. The inclusion of an additional tone while maintaining the same overall signal strength shows improved performance with a reduction in standard deviation of estimated distance from 5.64 mm to 3.42 mm in simulation. A four-tone system is also examined to show that this effect holds for additional tones.
58

Responding to Dangerous Accidents Among the Elderly: A Fall Detection Device with ZigBee-Based Positioning

Putnam, Michael R 01 September 2012 (has links) (PDF)
The following paper describes a fall detection and activity monitoring system with position detection based on Zigbee transceivers.The main objective is to reduce the time taken for emergency personnel to respond to falls among the elderly. Especially when the victim is unconscious or delirious, position tracking reduces location determination time within a busy hospital or nursing home environment and facilitates immediate treatment. Reduced response times correlate to decreased morbidity and mortality rates. Background is provided on the major wireless network advances currently deployed in a healthcare setting for asset and personnel tracking, etiology of falls, and several methods of detecting falls using sensors and image processing techniques. Data analysis proves that a precise coordinate tracking system was infeasible using the XBee RF module (based on the Zigbee protocol) due to environmental noise, a poor antenna construction and lack of precise signal strength measurements. A primitive scheme with lower resolution and higher reliability associating a single location with each Zigbee transceiver was employed. A pedometer function was added to the project to monitor the user’s daily activity and to potentially serve as a predictor of falls through the interpretation of mobility and gait patterns related to step counts.
59

Mesh Networking in Low Power Location Systems (Swarm)

Deo, Sonali January 2016 (has links)
Today, Internet of Things (IoT) is the driving force in making operations and processes smart. Indoor localization is such an application of IoT that has proven the potential of location awareness in countless scenarios, from mines to industries to even people. nanotron Technologies GmbH, based in Berlin, is one of the pioneers in low power location systems. nanotron's embedded location platform delivers location-awareness for safety and productivity solutions across industrial and consumer markets. The platform consists of chips, modules and software that enable precise real-time positioning and concurrent wireless communication. The ubiquitous proliferation of interoperable platforms is creating the locationaware Internet of Things. One of their product families is swarm. A swarm is a group of independent radios or nodes which facilitates the nodes to communicate with their immediate neighboring nodes to get each other’s positions. This position information is collected by one of the nodes (called gateway) and delivered to the host controller. However, the nodes need to be in range to communicate. The company wants to improve the range of communication and for that purpose; I am implementing a routing protocol with some additional changes for swarm, to allow out-of-range nodes to communicate via intermediate neighbors. This is called mesh networking which would result in so-called ‘mesh’ of nodes and would increase the range of swarm operation that could be beneficial in achieving uniform connectivity throughout large spaces without needing excessive number of gateways. This is of high importance because a node acting as gateway should be ‘awake’ all the time so that it can collect data efficiently, while the other nodes can beon power saving mode. Mesh networking will allow data collection even with fewer such gateways thereby being energy efficient while facilitating larger range of communication. This was made possible by adding the feature of allowing nodes to store messages for their neighbors in case they are asleep and wake up for the neighbors to transmit data. It is done using a schedule that is built and updated in addition to the routing protocol. The purpose of this thesis is to justify the implemented mesh routing protocol for swarm among all the other routing protocols available. It also focuses on the modifications and improvements that were devised to make the protocol tailored for how swarm works and to support Message Queuing Telemetry Transport (MQTT) on top of it, at a later stage. MQTT is a lightweight messaging protocol that provides resource-constrained network clients with a simple way to distribute information. It uses a publish/subscribe communication pattern and is used for machine-to-machine (M2M) communication and plays an important role in the Internet of Things. The implemented routing protocol also takes into consideration, the sleeping nodes, route maintenance through advertisements, hierarchical nature of mesh to make data collection more efficient, message formats keeping in mind the memory shortage, etc. The document gives a thorough overview of concepts, design implementation, improvements and tests to prove the importance of mesh networking in existing swarm.
60

Design of an Ultra-Wide Band based Indoor Positioning System

Li, Jun January 2018 (has links)
In recent years, the indoor positioning system (IPS) has attracted significant interests in both academical research and industrial development. It has seen many applications, such as hostage search and rescue, indoor navigation, and warehouse management, all of which can take advantage of precise positioning. However, in indoor environments, traditional methods, like the Global Positioning System (GPS), are usually either unreliable or incorrect because of the complicated physical characteristics of various objects reflecting and dispersing signals, such as the presence of people, walls, obstructions, and furniture. In contrast to other technologies such as WiFi and Bluetooth, which are not suitable to extract accurate timing information, UWB technology has the potential to reach center-meter level accuracy in indoor positioning. In this thesis, we developed a real-time, low-cost, IPS based on commercial-off-the-shelf UWB transceivers. Both the Two Way Ranging (TWR) and Time Difference of Arrival (TDOA) approaches have been implemented to obtain a target's location. To alleviate the effect of multipath propagation, we detect the presence of outliers by comparing the first path signal level and estimated receiving signal level. Moreover, we have designed the Printed Circuit Board (PCB) and evaluated performance by deploying the system both in a lab environment and in a two-story historical building during the 2018 Microsoft Indoor Localization Competition. The results show that we achieve a 28.9cm 95%-quantile 2D tracking error in the lab environment and a 92cm average tracking error for 3D localization on the Microsoft Indoor Localization Competition site. / Thesis / Master of Science (MSc)

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