The beginning of the 21st century sees great development and demands on wireless communication technologies. Wireless technologies, either based on a cable replacement or on a networked environment, penetrate our daily life more rapidly than ever. Low operational power, low cost, small form factor, and function diversity are the crucial requirements for a successful wireless product. The receiver??s front-end circuits play an important role in faithfully recovering the information transmitted through the wireless channel. Bluetooth is a short-range cable replacement wireless technology. A Bluetooth receiver architecture was proposed and designed using a pure CMOS process. The front-end of the receiver consists of a low noise amplifier (LNA) and mixer. The intermediate frequency was chosen to be 2MHz to save battery power and alleviate the low frequency noise problem. A conventional LNA architecture was used for reliability. The mixer is a modified Gilbert-cell using the current bleeding technique to further reduce the low frequency noise. The front-end draws 10 mA current from a 3 V power supply, has a 8.5 dB noise figure, and a voltage gain of 25 dB and -9 dBm IIP3. A front-end for dual-mode receiver is also designed to explore the capability of a multi-standard application. The two standards are IEEE 802.11b and Bluetooth. They work together making the wireless experience more exciting. The front-end is designed using BiCMOS technology and incorporating a direct conversion receiver architecture. A number of circuit techniques are used in the front-end design to achieve optimal results. It consumes 13.6 mA from a 2.5 V power supply with a 5.5 dB noise figure, 33 dB voltage gain and -13 dBm IIP3. Besides the system level contributions, intensive studies were carried out on the development of quality LNA circuits. Based on the multi-gated LNA structure, a CMOS LNA structure using bipolar transistors to provide linearization is proposed. This LNA configuration can achieve comparable linearity to its CMOS multi-gated counterpart and work at a higher frequency with less power consumption. A LNA using an on-chip transformer source degeneration is proposed to realize input impedance matching. The possibility of a dual-band cellular application is studied. Finally, a study on ultra-wide band (UWB) LNA implementation is performed to explore the possibility and capability of CMOS technology on the latest UWB standard for multimedia applications.

The following report describes the conception, pre-production, production, and post-production of the short film Yvonne & Clyde. Set in present day South East Texas, the film was shot in the Texas gulf towns of Bayside, Aransas Pass, and Port Aransas. The film follows the journey of the same two small time crooks named in its title as they drive towards the coast to extort money from an estranged relative. It’s an atmospheric piece centered on tone, setting, character, and performance rather than plot. It is a glimpse into the lives of these two long time friends on the last hundred or so miles of the trip. The majority of the writing contained in the report is a first-person narrative detailing the process of the film’s creation from its early genesis through to principal photography and into post-production. Included in the report is an early draft of the script. / text

The demand of Indoor Location Based Services LBS has increased over the past years as smart phone market expands. As a result, there's a growing interest in developing efficient and reliable indoor positioning systems for mobile devices. Wi-Fi signal strength fingerprint-based approaches attract more and more attention due to the wide deployment of Wi-Fi access points. Indoor positioning problem using Wi-Fi signal fingerprints can be viewed as a machine learning task to be solved mathematically. This thesis proposes an efficient and reliable Wi-Fi real-time indoor positioning system using machine learning algorithms. The proposed positioning system, together with a location server equipped with the same algorithms, are tested and evaluated in several indoor scenarios. Simulation and testing results show that the proposed system is a feasible LBS solution.

The demand of Indoor Location Based Services LBS has increased over the past years as smart phone market expands. As a result, there's a growing interest in developing efficient and reliable indoor positioning systems for mobile devices. Wi-Fi signal strength fingerprint-based approaches attract more and more attention due to the wide deployment of Wi-Fi access points. Indoor positioning problem using Wi-Fi signal fingerprints can be viewed as a machine learning task to be solved mathematically. This thesis proposes an efficient and reliable Wi-Fi real-time indoor positioning system using machine learning algorithms. The proposed positioning system, together with a location server equipped with the same algorithms, are tested and evaluated in several indoor scenarios. Simulation and testing results show that the proposed system is a feasible LBS solution.

Along with the huge growth of mobile devices in recent years we have seen a matching growth in interest for mobile applications, with location-aware applications experiencing rapid growth for mobile devices. Radiolocation from measurements of radio received signal strength has demonstrated excellent precision, although despite a decade of research there have been no wide-spread deployments of indoor location systems. The majority of the existing research has been focused towards producing improved precision at the cost of increased time requirements for system configuration and maintenance. This thesis proposes taking a step back from increasing complexity by giving up precision in exchange for simplicity and speed of deployment, while still providing sufficient accuracy for many indoor location tasks. This is accomplished by putting aside the standard x, y, z coordinate systems and by using a method based on defined areas. Carefully choosing the defined areas to include Wi-Fi access points and to have signal attenuating walls separating the area from the next, this work demonstrates locational accuracy of over 90% in most cases. While this method is not applicable to wide open areas that lack signal attenuating features, it is highly applicable to many indoor environments. / Graduate

Mobile phones are becoming a primary platform for information access. More and more people use their mobile devices as one of their major communication access tools. Commuters are increasingly carrying their mobile devices with them almost everywhere. Mobile devices fit perfectly into an ideal environment for realizing ubiquitous computing. A major aspect of ubiquitous computing is context-aware applications where the applications collect information about the environment that the user is in and use this information to achieve their goals or improve performance. The location of the device is one of the most important pieces of context information. Location awareness makes certain applications possible, e.g., recommending nearby businesses and tracking estimated routes, and greatly improves the performance of other applications, for example it can be associated with automobile navigation devices. A feature available to mobile applications in the Android platform makes it possible to determine a device's location without any additional hardware or sensor mechanisms, by simply using the native capability of the built-in wireless network card. Since the release of Android systems, there have been numerous applications developed to introduce new ways of tracking locations. Recently, there have been many papers on location estimation leveraging ubiquitous wireless networks. In this thesis, we develop an Android application to collect useful Wi-Fi information without registering a location listener with a network-based provider, such as Wi-Fi connections or data connections. Therefore it provides a passive, privacy-preserving, non-intrusive and power-saving way of achieving location awareness to Android mobile users. Accurate estimation of the location information can bring a more contextual experience to mobile users. We save the passively collected data of the IDs of Wi-Fi access points and the received signal strengths to a database in order to help us structure the data and analyse it. We employ some heuristics to infer the location information from the data. Our work presents a location tracking technique mainly based on Basic Service Set identification (BSSID) and/or Received Signal Strength Indicator (RSSI) using Wi-Fi information. It falls into one of the most active fields in mobile application development --location-based or location-aware applications.

This thesis assesses the impact of Wi-Fi radio frequency interference (RFI) on mobile application quality of experience (QoE). Wi-Fi is a wireless radio network for transferring data between two end points and is based on the IEEE 802.11 standards and operates in the unlicensed 2.4 GHz and 5 GHz radio frequency bands. This thesis explores the QoE of mobile applications when considering the impact of RFI caused by Wi-Fi access points (WAPs) within a campus Wi-Fi network. The research was conducted to assess the effect of RFI on mobile application network performance metrics. This is evaluated by collecting broadcasted WAPs within a campus network, assessing the experienced RFI, and evaluating the mobile application QoE at specific locations to assess the impact of the experienced interference. / Graduate

The Cash in Transit (CIT) industry demands reliable and innovative products from its suppliers to ensure safety and reliability within the industry. Product innovation has been directed at a bespoke tracking system for the Cash in Transit industry, which can meet its stringent requirements and excel above the capabilities of standard, readily available tracking systems. The presented research has investigated the state of the art in tracking and localisation systems and has highlighted Wi-Fi as a potential novel Cash in Transit tracking solution. With research into 2.4GHz Wi-Fi and the effects in a CIT environment, the technology has been understood and demonstrated in terms of its advantages and weaknesses when applied to CIT. The research has shown that 2.4GHz Wi-Fi is a novel and viable solution for both wide area tracking and localised tracking of a Cash in Transit security box by testing innovative ways of detecting theft using 2.4GHz Wi-Fi in a set of specific real-world scenarios. An embedded tracking system was developed and a thorough evaluation undertaken using a series of practical usage scenarios. The results show the proposed tracking capability is very effective and ready for initial effective use within a Cash in Transit security box.

El objetivo de esta memoria es el diseño de una plataforma inalámbrica que permita soportar una serie de servicios previamente determinados, como transmisión de datos y Voz sobre IP (VoIP); para posteriormente, probar el desempeño de esta maqueta con el fin de evaluar su funcionamiento. La plataforma está basada en la utilización de equipamiento específico de dispositivos S trixSystems y en una topología de red inalámbrica Mesh, también conocida como sistema de malla. Esta topología permite un aumento en el ancho de banda del sistema y un mayor respaldo ante fallas de los enlaces inalámbricos entre equipos, gracias a su sistema de troncales inalámbricas de comunicación que interconecta los nodos de la malla.

Made available in DSpace on 2016-08-29T15:08:23Z (GMT). No. of bitstreams: 1 tese_4820_Leonardo Machado.pdf: 1354188 bytes, checksum: d9d2f7ac89053ef56f095300d31462b1 (MD5) Previous issue date: 2011-05-30 / Este trabalho busca investigar em que bases se assenta a proposta de Walter Benjamin a necessidade de uma "politização da arte". Para tal buscarmos nos focar, principalmente, mas não exclusivamente, nos textos produsidos na década de 1930, período em que a produção dos ensaios de Benjaminaconteceu de uma forma mais explicitamente engajada politicamente O caráter fragmentário da produção deste pensador obrigou-nos a construir uma constelação de elementos que pudessem sustemtar nossa interpretação, saber: a)a concepção benjaminiana de história, bem como a influência desta concepção nas próprias formas de perceber, compreender e produzir das coletividades humanas;b) a relação entre os avanços e transformações das condições de produção material e intelectual, sobretudo as profundas modificações ocorridas graças ao vertiginoso desenvolvimento maerial ocasionado pela Revolução Industrial; c) o elemento propriamente político que forma o processo do capitalismo alterou fundamentalmente a experiência dos homens no mundo, assim como sua forma de compreender esse mesmo mundo , (nas artes na filosofia,na religião, etc.), torna-se então possivel de se compreeender a exigência de Benjamin de que, não apenas a "arte", mas que a produção intelectual sobre esta, a critica, se oriente para uma perspectiva politizada. Palavras-Chave: Walter Benjamin, politização da arte, História, Marxismo. FIlosofia da arte, Filosofia Contemporânea.