Refining Wi-Fi Based Indoor Localization with Li-Fi Assisted Model Calibration in Smart Buildings

In recent years, there has been an increasing number of information technologies utilized in buildings to advance the idea of "smart buildings". Among various potential techniques, the use of Wi-Fi based indoor positioning allows to locate and track smartphone users inside a building, therefore, location-aware intelligent solutions can be applied to control and of building operations. These location-aware indoor services (e.g., path finding, internet of things, location based advertising) demand real-time accurate indoor localization, which is a key issue to guarantee high quality of service in smart buildings. This paper presents a new Wi-Fi based indoor localization technique that achieves significantly improvement of indoor positioning accuracy with the help of Li-Fi assisted coefficient calibration. The proposed technique leverages indoor existing Li-Fi lighting and Wi-Fi infrastructure, and results in a cost-effective and user-convenient indoor accurate localization framework. In this work, experimental study and measurements are conducted to verify the performance of the proposed idea. The results substantiate the concept of refining Wi-Fi based indoor localization with Li-Fi assisted computation calibration.Comment: International Conference on Computing in Civil and Building Engineering (ICCCBE) 201

Indoor Location Estimation Utilizing Wi-Fi Signals

Global Positioning System is commonly been used for locating a position of a specific structure in finding geographical coordinates of a target area. Though, this application is still having a restricted in term of the signals, might not well operated and ineffective for indoor usage. The study aim is to develop positioning and localization systems by using Wi-Fi signal. Estimation was made based on the measurement of wireless distance for estimation the user’s coordinates. Analysis of views called the fingerprint algorithm is used in this study. The algorithm involved two phases over an offline and the online phases of the survey. Unidentified user’s coordinates will be in the online phase by comparative databases collected in the survey phase. MATLAB Graphical User Interface and Android has been used to develop a user interface for simulation purposes. Several analyses were performed to define the precision and efficiency of occurred error as the number of access points and the traffic environment. Finally, the user required to provide several inputs e.g. the exact location and the RSS from AP’s number at the present location. The simulation-based software will evaluate the estimation location and positioning of the user and will match to user’s precise locatio

RF-Based Location Using Interpolation Functions to Reduce Fingerprint Mapping

Indoor RF-based localization using fingerprint mapping requires an initial training step, which represents a time consuming process. This location methodology needs a database conformed with RSSI (Radio Signal Strength Indicator) measures from the communication transceivers taken at specific locations within the localization area. But, the real world localization environment is dynamic and it is necessary to rebuild the fingerprint database when some environmental changes are made. This paper explores the use of different interpolation functions to complete the fingerprint mapping needed to achieve the sought accuracy, thereby reducing the effort in the training step. Also, different distributions of test maps and reference points have been evaluated, showing the validity of this proposal and necessary trade-offs. Results reported show that the same or similar localization accuracy can be achieved even when only 50% of the initial fingerprint reference points are taken

Walkcompass: Finding Walking Direction Leveraging Smartphone\u27s Inertial Sensors

Determining moving direction with smartphone\u27s inertial sensors is a well known problem in the field of location service. Compass alone cannot solve this problem because smartphone\u27s compass cannot achieve high accuracy. Moreover GPS is not suitable in indoor scenario. Another well known approach is dead-reckoning but dead-reckoning needs to know phones initial orientation and over time it keeps accumulating errors and after some time the estimation becomes to noisy to use. To overcome these limitations, we propose a solution called WalkCompass which is specially designed for pedestrians keeping in mind the variation of force during normal human walk. Therefore the algorithm is inherently free from any error generated by the orientation of the phone. However, the performance of the system does not depend on the holding style or location of the phone in the body. The algorithm can work very fast to determine the direction of movement in real time and because of its low complexity the complete system can be implemented on a smartphone. WalkCompass does not need any bootstrapping and can produce results with the granularity of each step of a walk

where@UM : mobile application for positioning

Dissertação de mestrado integrado em Engenharia de ComunicaçõesO contexto em que uma aplicação é executada e/ou onde o respetivo utilizador se encontra é, cada vez mais, considerado fundamental para algumas áreas aplicacionais. A localização é uma das dimensões mais exploradas, existindo atualmente variadas tecnologias para determinar a posição dos dispositivos móveis pessoais, o que frequentemente corresponde à posição do seu utilizador, em ambientes interiores, onde o popular sistema de localização GPS não funciona. Nos últimos anos tem-se assistido ao surgimento de várias tecnologias que exploram as infraestruturas habitualmente instaladas em edifícios, oferecendo novas funcionalidades. Neste contexto destacam-se os sistemas de posicionamento baseados na técnica Wi-Fi fingerprinting. Estes sistemas têm vindo a ser alvo da atenção de muitos investigadores e empresas porque proporcionam uma solução de baixo custo para o posicionamento de pessoas e objetos em tempo real. No entanto, a construção dos mapas de rádio que suportam estas soluções continuam a constituir um desafio, principalmente para edifícios de grande escala. O propósito desta dissertação centra-se no desenvolvimento de um sistema de posicionamento baseado em Wi-Fi fingerprinting que, através de uma solução colaborativa, minimize ou suprima o problema da construção dos mapas de rádio para edifícios de grandes dimensões. A solução apresentada e descrita nesta dissertação baseia-se no desenvolvimento de uma aplicação para dispositivos móveis que combina os conceitos associados às redes sociais com a utilização de um motor de posicionamento já existente. O principal objetivo da solução passa por envolver os utilizadores do sistema, inconscientemente, na construção do mapa de rádio. A aplicação desenvolvida destina-se essencialmente à população da Universidade do Minho, mas não está limitada exclusivamente aos campi da mesma.The context which the application is executed and/or where the user finds itself is increasingly considered essential for some application areas. The location is one of the most explored dimensions, currently exists several technologies that estimate the position of personal mobile devices in indoor environments, which often corresponds to the user’s location, where the popular location system GPS does not work. In recent year many technologies that exploit the usually network deployed in buildings have emerged, offering new features. In this context positioning systems based on Wi-Fi fingerprinting have become very popular in recent years. These systems have been attracting the attention of many researchers and companies because they provide a low cost solution for real time positioning of both people and objects. However, the construction of the radio maps that support these solutions remain a challenge in indoor environments. This thesis focuses on the development of a positioning system based on Wi-Fi fingerprinting using a collaborative solution that reduces or eliminates the radio map construction problem for large-scale buildings. The solution presented and described in this thesis is based on developing an application for mobile devices which combines the concepts of social network with the use of an existing positioning engine. The main goal of this solution is to engage the system’s users on radio map construction. The developed application is mainly intended to the population of University of Minho, but not limited to the campuses limits