Progettazione ed implementazione di una piattaforma per il monitoraggio della copertura internet mobile attraverso un approccio di data-crowdsourcing

L'obiettivo di questa Tesi di laurea è di creare un applicativo che informi gli utenti sulle reti circostanti, in particolare sulla qualità del segnale, sulle zone in cui la rete mobile è carente e sui punti d'accesso aperti. Per l'implementazione del servizio, è stato adottato un modello di business, il Crowdsourcing, per raccogliere informazioni sui sistemi di connessione, affinché qualsiasi utente dotato di Smartphone possa aggiungere elementi al dataset.

Spatial computing per dispositivi mobile ed embedded

Questa tesi si focalizza sulle possibili tecnologie per realizzare comunicazioni opportunistiche fra dispositivi mobile ed embedded, con l'obiettivo di integrarle nel contesto di sistemi a larga scala situati, e con particolare riferimento al prototipo denominato "Magic Carpet". Vengono considerate in particolare le tecnologie WiFi ad-hoc e Bluetooth Low Energy su Android e Raspberry Pi.

Realizzazione di un'interfaccia universale in tecnologia Bluetooth Low Energy per sensori integrati

Lo scopo dell’elaborato di tesi è la progettazione e lo sviluppo di un’applicazione per il modulo Bluetooth Low Energy (BLE) Texas Instrument CC2650 in grado di leggere le informazioni da un sensore analogico, tramite un Analog-Digital- Converter (ADC), e di scambiare i dati con uno smartphone Android in tempo reale. L’interfaccia realizzata deve essere universale, ovvero dovrà essere compatibile con sensori di diverso tipo, facilmente estensibile per l’aggiunta di un numero maggiore di periferiche di lettura e utilizzabile con un ampio numero di dispositivi.

Sviluppo di sistemi mobile ad alta densita basati su comunicazioni opportunistiche wireless

In questa tesi ci si pone l'obiettivo di sviluppare sistemi distribuiti composti da device mobile che si scambiano informazioni tramite comunicazioni opportunistiche wireless peer-to-peer. Vengono inizialmente analizzate le principali tecnologie di comunicazione wireless adatte allo scopo, soffermandosi sulle reti Wifi ad hoc, delle quali vengono studiate le performance in sistemi di larga scala tramite il simulatore di reti ns-3. Successivamente viene esposto lo sviluppo di componenti software, basati su Akka Stream, per la costruzione di campi computazionali tramite comunicazioni opportunistiche tra device Android, effettuate tramite reti Wifi ad hoc.

A Passive WiFi Source Localization System based on Fine-grained Power-based Trilateration

Indoor localization systems become more interesting for researchers because of the attractiveness of business cases in various application fields. A WiFi-based passive localization system can provide user location information to third-party providers of positioning services. However, indoor localization techniques are prone to multipath and Non-Line Of Sight (NLOS) propagation, which lead to significant performance degradation. To overcome these problems, we provide a passive localization system for WiFi targets with several improved algorithms for localization. Through Software Defined Radio (SDR) techniques, we extract Channel Impulse Response (CIR) information at the physical layer. CIR is later adopted to mitigate the multipath fading problem. We propose to use a Nonlinear Regression (NLR) method to relate the filtered power information to propagation distances, which significantly improves the ranging accuracy compared to the commonly used log-distance path loss model. To mitigate the influence of ranging errors, a new trilateration algorithm is designed as well by combining Weighted Centroid and Constrained Weighted Least Square (WC-CWLS) algorithms. Experiment results show that our algorithm is robust against ranging errors and outperforms the linear least square algorithm and weighted centroid algorithm.

Passively Track WiFi Users with an Enhanced Particle Filter using Power-based Ranging

Passive positioning systems produce user location information for third-party providers of positioning services. Since the tracked wireless devices do not participate in the positioning process, passive positioning can only rely on simple, measurable radio signal parameters, such as timing or power information. In this work, we provide a passive tracking system for WiFi signals with an enhanced particle filter using fine-grained power-based ranging. Our proposed particle filter provides an improved likelihood function on observation parameters and is equipped with a modified coordinated turn model to address the challenges in a passive positioning system. The anchor nodes for WiFi signal sniffing and target positioning use software defined radio techniques to extract channel state information to mitigate multipath effects. By combining the enhanced particle filter and a set of enhanced ranging methods, our system can track mobile targets with an accuracy of 1.5m for 50% and 2.3m for 90% in a complex indoor environment. Our proposed particle filter significantly outperforms the typical bootstrap particle filter, extended Kalman filter and trilateration algorithms.

Sistema de guía para personas invidentes a través de bluetooth

El planteamiento inicial era proveer al individuo invidente de un sistema autónomo capaz de guiarle según sus preferencias. El resultado obtenido al finalizar este proyecto ha sido un dispositivo autónomo configurable por el usuario mediante una aplicación sw , desarrollada en la plataforma móvil Android capaz de comunicarse con el dispositivo autónomo(móvil personal). La idea de utilizar como plataforma de desarrollo sw Android, se basó fundamentalmente en que es código open source, es gratuito y está presente en el 70 por ciento de los móviles de Europa. La idea inicial era que ambos hubieran sido integrados en un mismo dispositivo, pero una vez comenzado el proyecto y habiendo evaluado los hábitos actuales, decidimos adaptar la idea general del proyecto, a nuestros días. Para ello hicimos uso del dispositivo móvil más usado hoy en día, como es nuestros teléfonos móviles, o más bien los llamado Smartphone, con los cuales podemos desde su aplicación originaria que es llamar, hasta realizar multitud de operaciones al mismo tiempo como puede ser comunicación por internet, posicionamiento via GPS, intercambio de ficheros por bluetooth… tantas como podamos programar. Sobre este último atributo, intercambio de información a través de bluetooth, es la interfaz que vamos a aprovechar para la realización de nuestro proyecto. Hoy en día el 90% de los Smartphone tiene entre sus características de conectividad la posibilidad de intercambiar información vía bluetooth. Una vez se tiene resuelto el interfaz entre el medio y el usuario se debe solucionar la forma de transformar la información para que los dispositivos móviles recojan la información y sepan discernir entre la información importante y la que no lo es. Para ello hemos desarrollado una tarjeta configurable, con un módulo bluetooth comercial para enviar la información. El resultado final de esta tarjeta proporciona una manera fácil de configurar diferentes mensajes que serán utilizados según la situación. ABSTRACT The initial approach consisted of a system that shows the way for blind people to get somewhere or something or provide to them important information, an autonomous system able to guide to their preference. After several analyses the project accomplish is a standalone device configurable by the user via an application sw, developed in Android mobile platform capable of communicating with the standalone device (personal cell phone). The decision of using the sw development platform of Android was due to the open source code concept and the great extent of presence on 70 percent of European mobiles. The first idea was that the sw and the device were integrated into a single device, but once the project had been started and having assessed the current habits, it has changed to be adapted to the present technology to get a better usability on the present-day. To achieve the project goals the most used mobile device today was used, our mobile phones, or rather called Smartphone, which you could use to phone your mother or perform many operations simultaneously such as communication online, positioning via GPS, bluetooth file trading program, etc. On this last attribute, information sharing via bluetooth, is the interface that it has been taken to complete the project. Today 90% of the Smartphone include in its connectivity features the ability to exchange information via bluetooth. Once that it was solved the interface between the environment and the final user, the next step incorporates the transformation of the information that the mobile devices collect from the environment to discern between the information the user configure to be notified or not. The hardware device that makes it possible is a configurable card with a bluetooth module that is able to send the information. The final result of this card provides an easy way to configure different messages, that we could use depending of the situation.

Interacción desde dispositivos Android vía Bluetooth, con juguete teledirigido, para su uso por personas con discapacidad

El Proyecto Fin de Carrera, con título, "Interacción desde dispositivos Android vía Bluetooth, con juguete teledirigido, para su uso por personas con discapacidad" pretende completar la primera versión de la aplicación sobre dispositivo Android para manejar un juguete teledirigido añadiendo nuevas formas de interactuar con el dispositivo Android. Para este caso, el juguete teledirigido es el mismo: el robot esférico llamado Sphero. Dicho robot posee una interfaz a través de la cual puede recibir instrucciones, y mediante las cuales, se puede poner en movimiento o iluminarse con diferentes colores. Esta ampliación facilitará la interacción del usuario con el dispositivo Android, además de ampliar la funcionalidad hacia la inversa: recibir los movimientos del robot Sphero en el dispositivo Android cuando es manejado con la mano. Completando la primera versión, como cumplimiento de este Proyecto Fin de Carrera, se han realizado una serie de mandos nuevos, los cuales abarcan desde el manejo del robot por instrucciones de voz, movimientos del dispositivo Android desde el que se ejecuta, describir una trayectoria dibujada previamente en el dispositivo Android, o, realizar una serie de movimientos corregidos mediante la aplicación gracias a los límites de movimientos para un usuario concreto que pueden introducirse. Además, completando lo anteriormente escrito, se ha desarrollado una aplicación web que registrará todos los datos de uso del juguete, la cual, explota una base de datos que almacena toda interacción con el juguete. Estos datos estarán asociados a un usuario, debido a que la aplicación Android debe perfilarse para el uso de un usuario concreto. El perfilado de usuario se ha completado añadiendo una serie de información que puede ser útil para la persona que analice el comportamiento de una persona con discapacidad que utilice la aplicación. Por último, se ha realizado un estudio de elementos externos que puedan facilitar la interacción con los dispositivos Android a personas que sufran alguna discapacidad. ABSTRACT. The Thesis, titled "Interaction from Android devices via Bluetooth, with remote control toy, for use by people with disabilities" project aims to complete the first version of the application on Android device to manage a remote control toy adding new ways of interacting to Android device. For this case, the remote control toy is the same: the spherical robot called Sphero. This robot has an interface through which it can receive instructions, and by means of which can be set in motion or illuminated with different colors. This expansion will facilitate user interaction with the Android device, and extend the functionality to reverse: receiving Sphero robot movements in the Android device when handled by hand. Completing the first version, in fulfillment of this Thesis, there have been a number of new controls, which range from control of robot by voice instructions, movements Android device from which it runs, describe a path drawn previously on your Android device, or perform a series of movements corrected by applying through limits of movement for a particular user can be made. Besides completing the above written, has developed a web application that will record all data on use of the toy, which exploits a database that stores all interaction with the toy. These data will be associated with a user, because the Android application should be outlined for the use of a particular user. The user profile is completed by adding a range of information that can be useful for the person to analyze the behavior of a disabled person to use the application. Finally, a study was made of external elements that can facilitate interaction with Android devices to people who suffer from a disability.

Control remoto de presentaciones mediante Raspberry PI y Android

Este proyecto fin de carrera trata de mejorar los sistemas actuales de control en la visualización de diapositivas. La solución adoptada constará de un sistema con modelo cliente-servidor. El servidor formado por un mini ordenador, en este caso una Raspberry Pi, que estará conectado al proyector de video. Este servidor se mantendrá a la espera de recibir una conexión entrante vía Bluetooth. Una vez se realice la conexión interpretará los comandos mandados por el cliente a través de una API con formato JSON y realizará las acciones indicadas para el control de la presentación. El cliente será una aplicación móvil para dispositivos Android. A través de ella el profesor accederá al servidor escaneando un código QR que será proyectado y una vez conectado enviará los comandos de control de la presentación, tales como abrir una presentación, avanzar y retroceder diapositiva, etc. La solución final deberá ser eficiente, sencilla de utilizar y con un bajo coste para resultar atractiva y ser así útil en el mundo real. Para ello se contará con valores añadidos como el poder iniciar la presentación desde el dispositivo móvil, el mostrar las notas de la diapositiva actual o contar con un temporizador para permitir un mejor control sobre el tiempo disponible para la presentación. ABSTRACT. This final project pursues the improvement of the current presentation control systems. The solution it provides is based on a server-client architecture. The server will be a mini PC, a Raspberry Pi model in this case, that will be connected to a video projector or a screen monitor. This server will remain idle waiting for an incoming Bluetooth connection. Once the connection is accepted the server will parse the commands sent by the client through a JSON API and will execute them accordingly to control the system. The client we decided to develop is an Android application. The speaker will be able to connect with the server by scanning a QR code that will be generated and displayed into the projector or screen monitor. Once the connection is accepted the client will sent the commands to control the slides, such as opening a presentation, move forward and backwards, etc. The adopted solution must be efficient, easy to use and with low cost to be appealing and useful to the real world. To accomplish the task this project will count with improvements over the current systems, such as the possibility to open a presentation from the smartphone, the visualization of the current slide notes from the mobile phone and a countdown timer to have a better control over the available time for the presentation.

Optimising QoE distribution for video applications through LTE-WiFi interworking

Mobile WiFi devices are becoming increasingly popular in non-seamless and user-controlled mobile traffic offloading alongside the standard WiFi hotspots. Unlike the operator-controlled hotspots, a mobile WiFi device relies on the capacity of the macro-cell for the data rate allocated to it. This type of devices can help offloading data traffic from the macro-cell base station and serve the end users within a closer range, but will change the pattern of resource distributions operated by the base station. We propose a resource allocation scheme that aims to optimize user quality of experience (QoE) when accessing video services in the environment where traffic offloading is taking place through interworking between a mobile communication system and low range wireless LANs. In this scheme, a rate redistribution algorithm is derived to perform scheduling which is controlled by a no-reference quality assessment metric in order to achieve the desired trade-offs between efficiency and fairness. We show the performance of this algorithm in terms of the distribution of the allocated data rates throughout the macro-cell investigated and the service coverage offered by the WiFi access point.

Enhanced connectivity and QoE through LTE-WiFi interworking in Smart Cities

Mobile communication and networking infrastructures play an important role in the development of smart cities, to support real-time information exchange and management required in modern urbanization. Mobile WiFi devices that help offloading data traffic from the macro-cell base station and serve the end users within a closer range can significantly improve the connectivity of wireless communications between essential components including infrastructural and human devices in a city. However, this offloading function through interworking between LTE and WiFi systems will change the pattern of resource distributions operated by the base station. In this paper, a resource allocation scheme is proposed to ensure stable service coverage and end-user quality of experience (QoE) when offloading takes place in a macro-cell environment. In this scheme, a rate redistribution algorithm is derived to form a parametric scheduler to meet the required levels of efficiency and fairness, guided by a no-reference quality assessment metric. We show that the performance of resource allocation can be regulated by this scheduler without affecting the service coverage offered by the WLAN access point. The performances of different interworking scenarios and macro-cell scheduling policies are also compared.

WiFi and LTE Coexistence in the Unlicensed Spectrum

Today, smart-phones have revolutionized wireless communication industry towards an era of mobile data. To cater for the ever increasing data traffic demand, it is of utmost importance to have more spectrum resources whereby sharing under-utilized spectrum bands is an effective solution. In particular, the 4G broadband Long Term Evolution (LTE) technology and its foreseen 5G successor will benefit immensely if their operation can be extended to the under-utilized unlicensed spectrum. In this thesis, first we analyze WiFi 802.11n and LTE coexistence performance in the unlicensed spectrum considering multi-layer cell layouts through system level simulations. We consider a time division duplexing (TDD)-LTE system with an FTP traffic model for performance evaluation. Simulation results show that WiFi performance is more vulnerable to LTE interference, while LTE performance is degraded only slightly. Based on the initial findings, we propose a Q-Learning based dynamic duty cycle selection technique for configuring LTE transmission gaps, so that a satisfactory throughput is maintained both for LTE and WiFi systems. Simulation results show that the proposed approach can enhance the overall capacity performance by 19% and WiFi capacity performance by 77%, hence enabling effective coexistence of LTE and WiFi systems in the unlicensed band.

Progettazione e sviluppo di un' applicazione mobile basata su Wi-Fi Direct per la comunicazione tra veicoli e pedoni

Questo documento di tesi si incentra principalmente sullo studio delle reti wireless mobili e dei relativi scenari di utilizzo. In particolare, come esse vengono applicate per il riconoscimento e la prevenzione di incidenti stradali. Vista l’importanza di questo problema a livello di sicurezza stradale, ho deciso di sviluppare un' applicazione per smartphone Android, in grado di riconoscere le attività di uso quotidiano dell’utente e associarle a dei comportamenti, come ad esempio quello di un ciclista, di un pedone o di un automobilista. Nel caso in cui, in uno scenario stradale i dispositivi si trovassero ad una distanza ravvicinata, possono comunicare tramite una connessione Wi-Fi Direct il loro ruolo e lanciare messaggi di pericolo per avvisare la loro presenza, in modo da prevenire collisioni stradali. La realtà in cui si vuole collocare questa applicazione è quella che viene chiamata Pedestrian Detection, già idea di General Motors, che la sta sviluppando sui futuri veicoli che metterà in produzione nei prossimi anni e che sicuramente integreranno funzionalità aggiuntive per la segnalazione di pericoli tramite smartphone e Wi-Fi Direct.

Sviluppo di un'applicazione Android per la comunicazione decentralizzata

L'utilizzo di percorsi non centralizzati per la comunicazione tra dispositivi mobili presenta notevoli vantaggi, tra i quali una maggiore sicurezza e segretezza e l'indipendenza da infrastrutture esterne (Internet). Gli studi e le implementazioni di questo tipo di funzionalità stanno emergendo recentemente di pari passo con i traguardi raggiunti nel campo della tecnologia mobile, ma si trovano ancora in uno stato sperimentale e poco fruibile in pratica. È stata sviluppata come proof of work un'applicazione che permette di diffondere messaggi tra dispositivi mobili senza connessione a internet, sfruttando un sistema di comunicazione (quasi) peer to peer. Viene descritta in generale l'architettura e il funzionamento dell'applicazione insieme a dei possibili casi d'uso. Inoltre vengono mostrati i metodi vagliati ed effettivamente utilizzati per implementare questo tipo di comunicazione, insieme ad altre caratteristiche secondarie (crittografia). Il risultato conseguito è a tutti gli effetti funzionante e viene ritenuto la soluzione migliore possibile tra tutte quelle trovate, ma presenta comunque diversi difetti. La conclusione raggiunta è che lo stato attuale dell'arte non permetta di raggiungere lo scopo prefissato in maniera ottimale, in quanto è necessario ricorrere a metodi poco funzionali a causa della mancanza di supporto alle tecnologie necessarie.