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.

Conventional Wi-Fi location estimation techniques using radio fingerprinting typically require a lengthy initial site survey. It is suggested that the lengthy site survey is a barrier to adoption of the radio fingerprinting technique. This research investigated two methods for reducing or eliminating the site survey and instead build the radio map on-the-fly. The first approach utilized a deterministic algorithm to predict the user's location near each access point and subsequently construct a radio map of the entire area. This deterministic algorithm performed only fairly and only under limited conditions, rendering it unsuitable for most typical real-world deployments. Subsequently, a probabilistic algorithm was developed, derived from a robotic mapping technique called simultaneous localization and mapping. The standard robotic algorithm was augmented with a modified particle filter, modified motion and sensor models, and techniques for hardware-agnostic radio measurements (utilizing radio gradients and ranked radio maps). This algorithm performed favorably when compared to a standard implementation of the radio fingerprinting technique, but without needing an initial site survey. The algorithm was also reasonably robust even when the number of available access points were decreased.

Στόχος της διπλωματικής εργασίας είναι η μελέτη των χαρακτηριστικών του ασύρματου καναλιού και πιο συγκεκριμένα κάποιων παραμέτρων του που παίζουν σημαντικό ρόλο στην καλύτερη κατανόηση του. Στο πρώτο κεφάλαιο γίνεται μία εισαγωγή σε έννοιες όπως η διάδοση του ηλεκτρομαγνητικού κύματος και το ασύρματο κανάλι σε γενικευμένη μορφή. Στο δεύτερο κεφάλαιο παρουσιάζονται όλες οι παράμετροι που επιδρούν και επηρεάζουν τη διάδοση του κύματος καθώς και οι διαφορετικοί τρόποι με τους οποίους το ηλεκτρομαγνητικό κύμα διαδίδεται στο χώρο. Το τρίτο κεφάλαιο διαπραγματεύεται την χρήση μοντέλων αλλά και την στατιστική περιγραφή του καναλιού λόγω του σύνθετου και πολύπλοκου χαρακτήρα της φύσης του καναλιού. Ακόμα εισάγεται η έννοια και η χρησιμότητα του συντελεστή Rice K. Στο τέταρτο κεφάλαιο έχουμε την παρουσίαση των μοντέλων που χρησιμοποιούνται στο ασύρματο κανάλι εσωτερικού χώρου για την τοπολογία του αεροδρομίου Αθηνών και την λήψη μετρήσεων σε αυτό ώστε να γίνει αξιολόγηση με βάση της μετρήσεις και να καταλήξουμε στο καταλληλότερο προς χρήση μοντέλο. Τέλος στο πέμπτο κεφάλαιο γίνεται μία θεωρητική προσέγγιση υπολογισμού του συντελεστή Κ, αλλά και ο υπολογισμός του με βάση μετρήσεις που πήραμε στο αεροδρόμιο και η εξαγωγή κάποιων συμπερασμάτων. / -

O Sistema de Posicionamento Global (GPS) permite uma grande variedade de aplicações civis e militares. Dentre as várias aplicações, uma de especial interesse é a navegação, que tem crescido muito nos últimos anos devido a fatores como menor custo, e fácil utilização desta tecnologia. Num sistema de navegação terrestre, assim como na navegação marítima, fluvial e aérea, um mapa digitalizado, ou imagem de satélite disponível da região de interesse é exibida na tela do computador de bordo e a posição do veículo é apresentada em "tempo real" a partir da posição fornecida por receptores GPS. Além disso, a comunicação disponível nos dias de hoje permite uma maior integração entre o veículo e o escritório. Finalmente, o Google Earth permite que se tenha acesso a uma grande quantidade de informações necessárias ao desenvolvimento de inúmeros trabalhos, permitindo inclusive a inserção de fotos e imagens para registro dos acontecimentos. O potencial deste tipo de sistema só foi possível a partir de maio de 2000, com a eliminação da SA (Selective Availability).Com isso, o posicionamento absoluto realizado por receptores de navegação (menos precisos do que os receptores geodésicos) foi aprimorado, podendo conseguir precisões da ordem de 10m, o que aumenta a qualidade de aplicações como a navegação terrestre. A proposta desta dissertação é descrever o desenvolvimento de um protótipo veicular para aplicações de campo em Geociências, onde foi incluída a navegação em tempo real, o uso da internet para a comunicação pessoal e interface de acesso ao Google Earth. O protótipo desenvolvido permite a extensão de parte da infra-estrutura de um laboratório para apoio das atividades de campo. / In our days the Global Positioning Systems (GPS) is a technology with a great variety of military and civilian applicability. Among this uses, navigation is one activity that is largely increasing in reason to lowering equipment prices and introduced facilities as easy to use technology. In practice, a system structured to navigate in terrestrial, maritime, fluvial or aerial way is formed by a GPS connected to an onboard computer and video equipped with appropriate software that process in a instantaneous mode (real time) all the information necessary to show on screen the geographical position of the vehicle. In parallel, new advances in network communication open the possibility to integrate completely the vehicle in movement with the staff in the office. Also, the Geoogle Earth™ and World Wide Web increase the facilities to view online the terrain and open the possibility to user interact directly with routines that insert local photo and images. Navigate with accuracy using a single-receiver GPS linked to a computer was only possibly after May of 2000, when the SA (Selective Availability) was excluded from GPS signal. Consequently, absolute positioning with one band handled GPS (low accuracy when compared to geodetic two bands GPS) was tested and the results show the availability to locate points in the Earth surface with an uncertainty degree not above than 10 meters (in terms of planimmetric coordinates). This performance increases the data quality and the ability of single-receiver GPS to be used to navigation purposes. In this work, it is assembled and tested a navigation system prototype installed in a vehicle with the objective to optimize field survey and adapted to some geosciences necessities, including the possibility to navigate in real time integrated with Internet facilities to personal communication and with an interface to access the Google Earth™. The configuration of the navigation system prototype elaborated in this project permit to extend to the field some facilities only accessible in a laboratory environment and consequently the results obtained with the system increased the performance of all the field work stages.

O Sistema de Posicionamento Global (GPS) permite uma grande variedade de aplicações civis e militares. Dentre as várias aplicações, uma de especial interesse é a navegação, que tem crescido muito nos últimos anos devido a fatores como menor custo, e fácil utilização desta tecnologia. Num sistema de navegação terrestre, assim como na navegação marítima, fluvial e aérea, um mapa digitalizado, ou imagem de satélite disponível da região de interesse é exibida na tela do computador de bordo e a posição do veículo é apresentada em "tempo real" a partir da posição fornecida por receptores GPS. Além disso, a comunicação disponível nos dias de hoje permite uma maior integração entre o veículo e o escritório. Finalmente, o Google Earth permite que se tenha acesso a uma grande quantidade de informações necessárias ao desenvolvimento de inúmeros trabalhos, permitindo inclusive a inserção de fotos e imagens para registro dos acontecimentos. O potencial deste tipo de sistema só foi possível a partir de maio de 2000, com a eliminação da SA (Selective Availability).Com isso, o posicionamento absoluto realizado por receptores de navegação (menos precisos do que os receptores geodésicos) foi aprimorado, podendo conseguir precisões da ordem de 10m, o que aumenta a qualidade de aplicações como a navegação terrestre. A proposta desta dissertação é descrever o desenvolvimento de um protótipo veicular para aplicações de campo em Geociências, onde foi incluída a navegação em tempo real, o uso da internet para a comunicação pessoal e interface de acesso ao Google Earth. O protótipo desenvolvido permite a extensão de parte da infra-estrutura de um laboratório para apoio das atividades de campo. / In our days the Global Positioning Systems (GPS) is a technology with a great variety of military and civilian applicability. Among this uses, navigation is one activity that is largely increasing in reason to lowering equipment prices and introduced facilities as easy to use technology. In practice, a system structured to navigate in terrestrial, maritime, fluvial or aerial way is formed by a GPS connected to an onboard computer and video equipped with appropriate software that process in a instantaneous mode (real time) all the information necessary to show on screen the geographical position of the vehicle. In parallel, new advances in network communication open the possibility to integrate completely the vehicle in movement with the staff in the office. Also, the Geoogle Earth™ and World Wide Web increase the facilities to view online the terrain and open the possibility to user interact directly with routines that insert local photo and images. Navigate with accuracy using a single-receiver GPS linked to a computer was only possibly after May of 2000, when the SA (Selective Availability) was excluded from GPS signal. Consequently, absolute positioning with one band handled GPS (low accuracy when compared to geodetic two bands GPS) was tested and the results show the availability to locate points in the Earth surface with an uncertainty degree not above than 10 meters (in terms of planimmetric coordinates). This performance increases the data quality and the ability of single-receiver GPS to be used to navigation purposes. In this work, it is assembled and tested a navigation system prototype installed in a vehicle with the objective to optimize field survey and adapted to some geosciences necessities, including the possibility to navigate in real time integrated with Internet facilities to personal communication and with an interface to access the Google Earth™. The configuration of the navigation system prototype elaborated in this project permit to extend to the field some facilities only accessible in a laboratory environment and consequently the results obtained with the system increased the performance of all the field work stages.

Cascading Web Services represent a collection of services offered in a system consisting of multiple devices and multiple interacting platform independent networks. ‘Cascading’ enables Web Services to exploit access in diverse environments without manual intervention. The aim of this thesis is to investigate how Mobile Web Services interact with multiple other Web Services by allowing the generated content to cascade. These services are demonstrated as a technical design solution, in a number of cases within the field of Learning technologies. Communication among devices is preceded using request-response commands by cascading these commands between different Web Services that are self-contained and independent on their context or state. The system signifies a typical Service Oriented Architecture (SOA) based on a distributed system. Cascading Web Services involve multiple transport networks including Bluetooth Technology, GPRS, Wi-Fi, and Wired Networks. Whereas the protocol of this communication is to bridge Wired and Wireless networks for data transactions, specifically from a Bluetooth location-based network. A number of particular cases will be illustrated in the context of ‘educational outdoor activities’, to demonstrate how the system solution works involving users.

O Sistema de Posicionamento Global (GPS) permite uma grande variedade de aplicações civis e militares. Dentre as várias aplicações, uma de especial interesse é a navegação, que tem crescido muito nos últimos anos devido a fatores como menor custo, e fácil utilização desta tecnologia. Num sistema de navegação terrestre, assim como na navegação marítima, fluvial e aérea, um mapa digitalizado, ou imagem de satélite disponível da região de interesse é exibida na tela do computador de bordo e a posição do veículo é apresentada em "tempo real" a partir da posição fornecida por receptores GPS. Além disso, a comunicação disponível nos dias de hoje permite uma maior integração entre o veículo e o escritório. Finalmente, o Google Earth permite que se tenha acesso a uma grande quantidade de informações necessárias ao desenvolvimento de inúmeros trabalhos, permitindo inclusive a inserção de fotos e imagens para registro dos acontecimentos. O potencial deste tipo de sistema só foi possível a partir de maio de 2000, com a eliminação da SA (Selective Availability).Com isso, o posicionamento absoluto realizado por receptores de navegação (menos precisos do que os receptores geodésicos) foi aprimorado, podendo conseguir precisões da ordem de 10m, o que aumenta a qualidade de aplicações como a navegação terrestre. A proposta desta dissertação é descrever o desenvolvimento de um protótipo veicular para aplicações de campo em Geociências, onde foi incluída a navegação em tempo real, o uso da internet para a comunicação pessoal e interface de acesso ao Google Earth. O protótipo desenvolvido permite a extensão de parte da infra-estrutura de um laboratório para apoio das atividades de campo. / In our days the Global Positioning Systems (GPS) is a technology with a great variety of military and civilian applicability. Among this uses, navigation is one activity that is largely increasing in reason to lowering equipment prices and introduced facilities as easy to use technology. In practice, a system structured to navigate in terrestrial, maritime, fluvial or aerial way is formed by a GPS connected to an onboard computer and video equipped with appropriate software that process in a instantaneous mode (real time) all the information necessary to show on screen the geographical position of the vehicle. In parallel, new advances in network communication open the possibility to integrate completely the vehicle in movement with the staff in the office. Also, the Geoogle Earth™ and World Wide Web increase the facilities to view online the terrain and open the possibility to user interact directly with routines that insert local photo and images. Navigate with accuracy using a single-receiver GPS linked to a computer was only possibly after May of 2000, when the SA (Selective Availability) was excluded from GPS signal. Consequently, absolute positioning with one band handled GPS (low accuracy when compared to geodetic two bands GPS) was tested and the results show the availability to locate points in the Earth surface with an uncertainty degree not above than 10 meters (in terms of planimmetric coordinates). This performance increases the data quality and the ability of single-receiver GPS to be used to navigation purposes. In this work, it is assembled and tested a navigation system prototype installed in a vehicle with the objective to optimize field survey and adapted to some geosciences necessities, including the possibility to navigate in real time integrated with Internet facilities to personal communication and with an interface to access the Google Earth™. The configuration of the navigation system prototype elaborated in this project permit to extend to the field some facilities only accessible in a laboratory environment and consequently the results obtained with the system increased the performance of all the field work stages.

Made available in DSpace on 2014-06-12T16:01:28Z (GMT). No. of bitstreams: 2 arquivo9413_1.pdf: 1325696 bytes, checksum: e7de71518a27dfd5c073cfbd0f623230 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2012 / As redes sem o padr~ao IEEE 802.11 est~ao presentes nos mais diversos ambientes e continuam a expandir-se devido, principalmente, ao inegavel aumento da produtividade para as empresas. Ao mesmo tempo que se expandem, essas redes levam consigo suas vulnerabilidades. As redes sem fio contam com mecanismos para protec~ao de quadros de dados e tambem para protec~ao dos quadros de gerenciamento, apenas os quadros de controle n~ao contam com uma protec~ao padronizada pelo IEEE. A aus^encia de protec~ao possibilita atividades maliciosas que se utilizam de tecnicas de manipulac~ao, falsificac~ao e reinjec~ao de quadros de controle que geram negac~ao de servico na rede. Esta dissertac~ao prop~oe um mecanismo de protec~ao dos quadros de controle do IEEE 802.11, que faz uso de um numero de sequ^encia e de um codigo de autenticac~ao de mensagem a fim de evitar que estac~oes maliciosas, n~ao pertencentes a rede, tenha sucesso ao manipular, falsicar ou reinjetar quadros de controle que levariam a indisponibilidade da rede. O mecanismo proposto destaca-se por proteger todos os quadros de controle indistintamente, possuir um maior grau de seguranca e introduz, nesses quadros, um aumento de tamanho signi- ficativamente menor em comparac~ao aos trabalhos relacionados que tambem se prop~oe a proteger todos os quadros de controle

Submitted by marco aurélio santos (marrco.santos@gmail.com) on 2018-07-30T01:42:52Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) msc_dissertacao_marcoSantos.pdf: 6142716 bytes, checksum: 17219663e0f7676d5c438178de493d89 (MD5) / Approved for entry into archive by Secretaria PPGI (secretariappgi@icomp.ufam.edu.br) on 2018-07-30T18:34:28Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) msc_dissertacao_marcoSantos.pdf: 6142716 bytes, checksum: 17219663e0f7676d5c438178de493d89 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-07-31T18:29:17Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) msc_dissertacao_marcoSantos.pdf: 6142716 bytes, checksum: 17219663e0f7676d5c438178de493d89 (MD5) / Made available in DSpace on 2018-07-31T18:29:17Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) msc_dissertacao_marcoSantos.pdf: 6142716 bytes, checksum: 17219663e0f7676d5c438178de493d89 (MD5) Previous issue date: 2018-04-16 / Internal positioning systems allow the localization of people or certain objects indoors, as well as assist in navigation and orientation. Proposals for indoor location systems based on only one technology have achieved unsatisfactory performance in localization, mainly due to the limitations in relation to the conflicting characteristics present in these environments. This work aims at the development of a hybrid location system, integrating the PDR and Wi-Fi technologies, which aims to provide the location of a user in an internal environment, allowing the user to move around and visualize their current location through a representation on a map. The results were satisfactory, including the direct influence of factors such as: physical characteristics (height, body mass, size of the past), smartphone location, speed of the adopted march and adoption of constant movements. / Os sistemas de posicionamento internos permitem a localização de pessoas ou certos objetos em ambientes internos, assim como ajudam na navegação e orientação. As propostas de sistemas de localização para ambientes internos baseados em somente uma tecnologia tem alcançado desempenho insatisfatório na localização, principalmente, devido às limitações em relação às características conflitantes presentes nesses ambientes. Este trabalho tem como objetivo o desenvolvimento de um sistema híbrido de localização, integrando as tecnologias PDR e Wi-Fi, que visa fornecer a localização de um usuário em um ambiente interno, permitindo ao usuário locomover-se e visualizar a sua localização corrente através de uma representação em um mapa. Os resultados obtidos foram satisfatórios, constando-se a direta influência de fatores como: características físicas (altura, massa corporal, tamanho da passada) do usuário, localização do smartphone, velocidade da marcha adotada e adoção de movimentos constantes.

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.