564 research outputs found

    An experiment in remote manufacturing using the advanced communications technology satellite

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    The goal of the completed project was to develop an experiment in remote manufacturing that would use the capabilities of the ACTS satellite. A set of possible experiments that could be performed using the Advanced Communications Technology Satellite (ACTS), and which would perform remote manufacturing using a laser cutter and an integrated circuit testing machine are described in detail. The proposed design is shown to be a feasible solution to the offered problem and it takes into consideration the constraints that were placed on the experiment. In addition, we have developed two more experiments that are included in this report: backup of rural telecommunication networks, and remote use of Synthetic Aperture Radar (SAR) data analysis for on-site collection of glacier scattering data in the Antarctic

    GPU-oriented architecture for an end-to-end image/video codec based on JPEG2000

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    Modern image and video compression standards employ computationally intensive algorithms that provide advanced features to the coding system. Current standards often need to be implemented in hardware or using expensive solutions to meet the real-time requirements of some environments. Contrarily to this trend, this paper proposes an end-to-end codec architecture running on inexpensive Graphics Processing Units (GPUs) that is based on, though not compatible with, the JPEG2000 international standard for image and video compression. When executed in a commodity Nvidia GPU, it achieves real time processing of 12K video. The proposed S/W architecture utilizes four CUDA kernels that minimize memory transfers, use registers instead of shared memory, and employ a double-buffer strategy to optimize the streaming of data. The analysis of throughput indicates that the proposed codec yields results at least 10× superior on average to those achieved with JPEG2000 implementations devised for CPUs, and approximately 4× superior to those achieved with hardwired solutions of the HEVC/H.265 video compression standard

    Statistical lossless compression of space imagery and general data in a reconfigurable architecture

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    Efficient Algorithms for Large-Scale Image Analysis

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    This work develops highly efficient algorithms for analyzing large images. Applications include object-based change detection and screening. The algorithms are 10-100 times as fast as existing software, sometimes even outperforming FGPA/GPU hardware, because they are designed to suit the computer architecture. This thesis describes the implementation details and the underlying algorithm engineering methodology, so that both may also be applied to other applications

    Wireless Communication Options for a Mobile Ultrasound System

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    A mobile ultrasound system has been developed, which makes ultrasound examinations possible in harsh environments without reliable power sources, such as ambulances, helicopters, war zones, and disaster sites. The goal of this project was to analyze three different wireless communication technologies that could be integrated into the ultrasound system for possible utilization in remote data applications where medical information may be transmitted from the mobile unit to some centralized base station, such as an emergency room or field hospital. By incorporating wireless telecommunication technology into the design, on site medical personnel can be assisted in diagnostic decisions by remote medical experts. The wireless options that have been tested include the IEEE 802.11g standard, mobile broadband cards on a 3G cellular network, and a mobile satellite terminal. Each technology was tested in two phases. In the first phase, a client/server application was developed to measure and record general information about the quality of each link. Four different types of tests were developed to measure channel properties such as data rate, latency, inter-arrival jitter, and packet loss using various signal strengths, packet sizes, network protocols, and traffic loads. In the second phase of testing, the H.264 Scalable Video Codec (SVC) was used to transmit real-time ultrasound video streams over each of the wireless links to observe the image quality as well as the diagnostic value of the received video stream. The information gathered during both testing phases revealed the abilities and limitations of the different wireless technologies. The results from the performance testing will be valuable in the future for those trying to develop network applications for telemedicine procedures over these wireless telecommunication options. Additionally, the testing demonstrated that the system is currently capable of using H.264 SVC compression to transmit VGA quality ultrasound video at 30 frames per second (fps) over 802.11g while QVGA resolution at frame rates between 10 and 15 fps is possible over 3G and satellite networks

    High Speed S-band Communications System for Nanosatellites

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    3Cat-3 is a nanosatellite based on the 6 unit cubesat standard. Its payload is an optical multispectral imager that imposes stringent downlink requirements for a nanosatellite. This TFG is based on the experience gained in 3Cat-1 and 3Cat-2 communications systems to develop a "high speed" (goal >= 5 Mbps) downlink for nanosatellites based on the TI CC3200.In order to accomplish the objectives of the next generation of nanosatellites high-speed downlinks have to be designed. This goal faces stringent design constraints as nanosatellites are limit in power, processing capabilities and dimensions. In the quest for higher bit rates the widely used VHF band has to be replaced for higher frequency bands and the link budged margin tightened, decreasing the SNR at reception. The proposed solution uses COTS 2.4 GHz WiFi adapters as transceivers. Range limitations imposed by the default 802.11 mode of operation are bypassed by using packet forging and injection at transmission jointly with monitor mode at reception. A loss-resilient unidirectional downlink is achieved by using application-layer encoding by means of LPDC-Staircase codes. This solution has been already implemented in 3CAT-2, a 6 unit cubesat GNSS-R mission to be launched in July 2016. In addition, bursts of errors are combated by using Reed-Solomon. The system has been tested under Doppler shift and scintillation effects, and a 188Km link between Barcelona and Mallorca has been performed, showing satisfactory results

    Run-Length Coding Algorithm Based Satellite Image Compression

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    Image compression is an application based on data compression of the digital images. Its main objective is to reduce the redundancy of the image data for storing and transmitting data in an easy way. In this system we are proposing a compression technique based on the Run-length coding algorithm based on satellite image compression. The Run-length coding algorithm is a part of the Lossless compression algorithm. The performance evolution can be done by calculating the PSNR values of the compressed images

    Use of 3G mobile phone links for teleconsultation between a moving ambulance and a hospital base station

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    The importance of this paper lays in its suggestion: minimise the time for the initial treatment of a patient. As soon as an ambulance receives a patient, a videoconferencing session can be initiated between the moving vehicle and a base station in a hospital where a medical consultant resides. The communication link is implemented using 3G networks. Effectively, the use of such a system can decrease fatality on patients being transferred to A&E, as expert opinion can be obtained straight away. This paper was repeatedly cited in IEEE papers and formed the basis for an EPSRC proposal that was recently submitted

    An fpga-based loco-ans implementation for lossless and near-lossless image compression using high-level synthesis

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    MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliationsIn this work, we present and evaluate a hardware architecture for the LOCO-ANS (Low Complexity Lossless Compression with Asymmetric Numeral Systems) lossless and near-lossless image compressor, which is based on JPEG-LS standard. The design is implemented in two FPGA generations, evaluating its performance for different codec configurations. The tests show that the design is capable of up to 40.5 MPixels/s and 124 MPixels/s per lane for Zynq 7020 and UltraScale+ FPGAs, respectively. Compared to the single thread LOCO-ANS software implementation running in a 1.2 GHz Raspberry Pi 3B, each hardware lane achieves 6.5 times higher throughput, even when implemented in an older and cost-optimized chip like the Zynq 7020. Results are also presented for a lossless only version, which achieves a lower footprint and approximately 50% higher performance than the version that supports both lossless and near-lossless. Interestingly, these great results were obtained applying High-Level Synthesis, describing the coder with C++ code, which tends to establish a trade-off between design time and quality of results. These results show that the algorithm is very suitable for hardware implementation. Moreover, the implemented system is faster and achieves higher compression than the best previously available near-lossless JPEG-LS hardware implementationThis research was funded in part by the Spanish Research Agency under the project AgileMon (AEI PID2019-104451RB-C21
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