International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper discusses the design and implementation of a microcomputer system that functions as the central processing unit for performing servo system control, tracking mode determination, operator interface, switching, and logic operations. The computer hardware consists of VMEbus compatible boards that include a Motorola 32-bit MC68020 microprocessor-based CPU board, and a variety of interface boards. The computer is connected to the Radio Frequency system, Antenna Control Unit, azimuth and elevation servo systems, and other systems of the Advanced Transportable Telemetry Acquisition System (TTAS-A) through extensive serial, analog, and digital input/output interfacing. The software platform consists of a commercially-acquired real-time multi-tasking operating system, and in-house developed device drivers and tracking system software. The operating system kernel is written in assembly language, while the application software is written using the C programming language. To enhance the operation of the TTAS-A, software was also developed to provide color graphics, CRT menus, printer listings, interactive real-time hardware/software diagnostics, and a GPIB (IEEE-488 bus) interface for Automated Testing System support.

The optimization, control, and characterization of engineering components or systems require fast, repeated, and accurate evaluation of a partial-differential-equation-induced input-output relationship. We present a technique for the rapid and reliable prediction of linear-functional outputs of elliptic partial differential equations with affine parameter dependence. The method has three components: (i) rapidly convergent reduced{basis approximations; (ii) a posteriori error estimation; and (iii) off-line/on-line computational procedures. These components -- integrated within a special network architecture -- render partial differential equation solutions truly "useful": essentially real{time as regards operation count; "blackbox" as regards reliability; and directly relevant as regards the (limited) input-output data required. / Singapore-MIT Alliance (SMA)

The problems caused by commercial drones in air traffic, airports, and vital and military installations have increased the demand for drone detection and tracking systems. An acoustic beamforming system that tracks audio sources using 256 microphones in real-time was extended to detect and track drones. This thesis studied software-defined, multi-channel, real-time filtering solutions to improve the systems' drone detection and tracking capabilities. The sound frequencies of drone sound and disturbance noise were analyzed to create a suitable filter. Methods for implementing this filter on all channels while still operating in real-time were studied. SIMD intrinsics were used to create a few candidate algorithms, and a GPU algorithm was created as well. These algorithms were compared to each other based on execution time metrics, and the system was also analyzed for performance degradation and placement of the filtering algorithms. The results of the isolated execution time of the filtering algorithms showed the best SIMD algorithm to be operating at 0.41 milliseconds and the GPU algorithm at 0.12 milliseconds when filtering 256 samples from all 256 channels. The real-time constraint was around 5.2 milliseconds, meaning both solutions operated well below the limit. The results of the system's drone detection and tracking capabilities, when placed outdoors in a windy environment, showed the system clearly finding the drone 48% of the time without any filtering and 89% of the time with filtering. The signal-to-noise ratio was also improved by 21dB by using this filter. The results show that a software-defined multi-channel, real-time filter operating on a large data stream is a viable solution to real-time DSP applications. When specializing a beamforming application in tracking a desired frequency, filtering was revealed to be a good solution.

Real time computing has become a vital part in military applications. Moreover certain operations require that the soldiers carry computing devices to assist them. These devices, besides providing them with location-based information, should also be transmitting the requested data. In this thesis, we present a portable wireless display prototype, which renders the desktop of a remote computer. The prototype functions under the range of an 802.11b or Bluetooth wireless network. The Software interfacing is done with Virtual Network Computing (VNC). This thesis is a first step towards analyzing and creating head/wrist mounted displays capable of transmitting images from a remote computer. The thesis starts with an overview and proceeds with a discussion on the concepts involved behind the functioning of the prototype. It then provides a detailed description of the how the prototype was built, followed by a performance test and its analysis and concludes by summarizing the results achieved.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-08-01T17:19:06Z No. of bitstreams: 1 LORENO FEITOSA DE OLIVEIRA - DISSERTAÇÃO PPGCC 2007..pdf: 5757457 bytes, checksum: b80a82ad9c8975205f58ab024e542115 (MD5) / Made available in DSpace on 2018-08-01T17:19:06Z (GMT). No. of bitstreams: 1 LORENO FEITOSA DE OLIVEIRA - DISSERTAÇÃO PPGCC 2007..pdf: 5757457 bytes, checksum: b80a82ad9c8975205f58ab024e542115 (MD5) Previous issue date: 2007-08-31 / Redes pessoais sem fio, WPANs (WirelessPersonalAreaNetworks), são redes de curto alcance, em torno de 10 m, cujo centro é o usuário. O cenário de uso geral é aquele onde dispositivos dentro da área de cobertura da WPAN comunicam-se diretamente entre si ou com recursos do mundo exterior (recursos fora da WPAN) através de pontos de acesso que ofereçam esse tipo de encaminhamento de dados. WPANs vêm ganhando atenção nos últimos anos principalmente devido ao surgimento de novas tecnologias de transmissão sem fio que viabilizam este tipo de rede, particularmente Bluetooth. De fato, o desenvolvimento das WPANs confunde-se com o desenvolvimento do Bluetooth, que tem sido usado como ponto de partida em diversos estudos e protótipos nesta área. Sendo a mobilidade de usuários a principal característica das WPANs, um número de questões surge quando se pensa no desenvolvimento de aplicações direcionadas para esse novo paradigma. Uma das principais se refere à gerência de handoff. Handoff é o processo pelo qual conexões, rotas de dados, e estados associados à provisão de algum serviço são transferidos entre pontos de acesso à medida que o usuário se move entre suas áreas de cobertura. Apesar de seu alinhamento com o modelo de rede das WPANs, Bluetooth não possui facilidades para o gerenciamento de handoffs além de suas operações padrão para localização e conexão com dispositivos próximos; inquiry e paging respectivamente. Adicionalmente, o tráfego de dados dessas operações pela interface Bluetooth possui prioridade sobre o tráfego de dados das aplicações do usuário. Essa característica possui especial impacto sobre um tipo particular de aplicações: aquelas que demandam transferências de dados em tempo-real, como aplicações de streaming. Ao tornar o canal sem fio indisponível para o tráfego de dados, seja pela temporária perda total de conexão com pontos de acesso durante handoffs ou por preempção da interface para as operações citadas, aplicações de tempo-real têm seus desempenhos comprometidos devido à quebra de requisitos temporais associados às suas trocas de dados. Nesse contexto, neste trabalho é proposto um protocolo para gerência dehandoffs em WPANs Bluetooth. O protocolo apresentado é voltado para o uso com aplicações que demandam transferências de dados em tempo-real, sendo demonstrada nesse trabalho sua adequação para esse tipo de aplicação. O protocolo apresentado foi projetado levando-se em consideração as limitações dos potenciais dispositivos clientes (pequenos dispositivos móveis com pouco poder de processamento, pouca memória, largura de banda restrita, etc). Assim, são transferidas para os pontos de acesso todas as atividades relativas às transições entre pontos de acesso dos dispositivos móveis. O protocolo apresentado descarta ainda a necessidade de sinalizações ou quaisquer outras trocas de mensagens entre dispositivos móveis e pontos de acesso durante os handoffs. Por utilizar apenas operações padronizadas do Bluetooth, viabiliza-se seu uso junto com qualquer dispositivo programável equipado com interface Bluetooth de acordo com a especificação, sendo portanto dispensada a necessidade de, por exemplo, modificar a pilha Bluetooth dos dispositivos. / Wireless personal area networks (WPANs), are a mobile short range wireless network, with typical range of 10 meters, where the user is the center. The general usage scenario is where devices within the WPANs range communicate directly to each other or with resources from the external world (outside the WPAN) through access points which offer routing service. WPANs have been gaining attention over the last few years mainly due the emergence and popularization of novel wireless communication technologies that enable this kind of network, notably Bluetooth. In fact, the development of WPANs is closely related to the development of Bluetooth, which has been used as starting point to several studies and prototypes in this field. As the user mobility is the main feature of WPANs, a number of questions arise when developing applications targeted to this new paradigm. One of the most important refers to the handoff management. Handoff is the process through which network connections, routes, and states associated to services in course are seamlessly transferred between access points as the user moves through their coverage areas. Despite its alignment with the WPAN's network model, Bluetooth has no facilities for aiding the management of handoffs besides its standard operations for querying nearby devices and connect to them, inquiry and paging respectively. Moreover, the data traffic of these operations has priority over user applications' data traffic. This property has special impact for a particular kind of application: those that require real-time data transfer, such as streaming applications. When the wireless channel is unavailable for data transfers, with temporary connection loss with access points during handoffs, or interface preemption for the inquiry and paging operations, real-time applications have their performance compromised in consequence of violation of temporal requirements. In this work, a protocol for managing handoffs in Bluetooth-based WPANs is presented. The protocol is focused on the use of applications that demand real-time data transfers. The adequacy of the protocol to this kind of application is analyzed through a case study for an audio streaming application. The protocol is designed focusing on the limitations of potential client devices (small portable devices with limited computational power, memory, bandwidth, battery life, etc). Therefore, all the handoff management operations are transferred to access points. There is no need of signaling or any other kind of coordination or message exchange between access points and mobile devices during handoffs. Due to the use of standardized Bluetooth operations, any programmable device with a standard complaint Bluetooth interface can be used without changes on any underlying software layer, such as the Bluetooth stack. It is also presented a formal modelling and validation of the protocol to ensure it behaves according to its specification. The formal model is important to understand the protocol, unanbiguous documentation, and to easy the validation of changes and extension by automatic simulation and proof of properties.

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Panoramas or stitched images are used in topographical mapping, panoramic 3D reconstruction, deep space exploration image processing, medical image processing, multimedia broadcasting, system automation, photography and other numerous fields. Generating real-time panoramic images in small embedded computer is of particular importance being lighter, smaller and mobile imaging system. Moreover, this type of lightweight panoramic imaging system is used for different types of industrial or home inspection. A real-time handheld panorama imaging system is developed using embedded real-time Linux as software module and Gumstix Overo and PandaBoard ES as hardware module. The proposed algorithm takes 62.6602 milliseconds to generate a panorama frame from three images using a homography matrix. Hence, the proposed algorithm is capable of generating panorama video with 15.95909365 frames per second. However, the algorithm is capable to be much speedier with more optimal homography matrix. During the development, Ångström Linux and Ubuntu Linux are used as the operating system with Gumstix Overo and PandaBoard ES respectively. The real-time kernel patch is used to configure the non-real-time Linux distribution for real-time operation. The serial communication software tools C-Kermit, Minicom are used for terminal emulation between development computer and small embedded computer. The software framework of the system consist UVC driver, V4L/V4L2 API, OpenCV API, FFMPEG API, GStreamer, x264, Cmake, Make software packages. The software framework of the system also consist stitching algorithm that has been adopted from available stitching methods with necessary modification. Our proposed stitching process automatically finds out motion model of the Spherical camera system and saves the matrix in a look file. The extracted homography matrix is then read from look file and used to generate real-time panorama image. The developed system generates real-time 180° view panorama image from a spherical camera system. Beside, a test environment is also developed to experiment calibration and real-time stitching with different image parameters. It is able to take images with different resolutions as input and produce high quality real-time panorama image. The QT framework is used to develop a multifunctional standalone software that has functions for displaying real-time process algorithm performance in real-time through data visualization, camera system calibration and other stitching options. The software runs both in Linux and Windows. Moreover, the system has been also realized as a prototype to develop a chimney inspection system for a local company. / Main Uddin-Al-Hasan, E-mail: main.hasan@gmail.com