12,794 research outputs found

    Navigation system and method

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    In a global positioning system (GPS), such as the NAVSTAR/GPS system, wherein the position coordinates of user terminals are obtained by processing multiple signals transmitted by a constellation of orbiting satellites, an acquisition-aiding signal generated by an earth-based control station is relayed to user terminals via a geostationary satellite to simplify user equipment. The aiding signal is FSK modulated on a reference channel slightly offset from the standard GPS channel. The aiding signal identifies satellites in view having best geometry and includes Doppler prediction data as well as GPS satellite coordinates and identification data associated with user terminals within an area being served by the control station and relay satellite. The aiding signal significantly reduces user equipment by simplifying spread spectrum signal demodulation and reducing data processing functions previously carried out at the user terminals

    The STM32 microcontroller based pulse intensity registration system for the neutron monitor

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    We present the outlines of a new microcontroller based data acquisition system which is aimed for reliable operation in a typical cosmic ray particle registration experiment. The system supports connection of up to 16 input signals and ensures the following operation functionality: (1)stable monitoring of the intensity of a digital pulse signal, or digitization of a continuous potential level with a low time resolution (typically, in the limits of 1-100s); (2)registration of a continuous high-resolution (up to 5-10us) time series of the intensity of input signal; (3)synchronization of registered time series with both external (physical) or local (program-based) trigger signal; (4)possibility of an on-the-fly change of the whole configuration of informational system (both the combination and type of input signals, time resolution and sum duration of the time series measurements, trigger logic, etc) immediately in operation time through convenient communication with a plain text message in dialog mode. In particular, the considered system is applied now for a long-term, high precision measurement of the counting rate of neutron signals at the NM64 type neutron supermonitor of the Tien~Shan mountain cosmic ray station, with a real-time representation of the whole collected dataset in a WWW database.Comment: communication at ISVHECRI 2016 and at the "10 Years Neutron Monitor Database" NMDB Worksho

    STANDARDS IN CONTROL AND PROTECTION TEHNOLOGY FOR ELECTRIC POWER SYSTEMS

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    The features of the standard IEC 16850 with respect to intelligent applications in substations are summarized. It is shown how modeling of functions independently from its allocation to devices allows optimizing existing applications and opening up for future intelligent applications. The data model provides all information in a substation needed not only for control and protection functions but also about the IEDs and the switchgear configuration.electric power systems

    STANDARDS IN CONTROL AND PROTECTION TEHNOLOGY FOR ELECTRIC POWER SYSTEMS

    Get PDF
    The features of the standard IEC 16850 with respect to intelligent applications in substations are summarized. It is shown how modeling of functions independently from its allocation to devices allows optimizing existing applications and opening up for future intelligent applications. The data model provides all information in a substation needed not only for control and protection functions but also about the IEDs and the switchgear configuration.electric power system

    Development and flight test of a helicopter, X-band, portable precision landing system concept

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    A beacon landing system (BLS) is being developed and flight tested as a part of NASA's Rotorcraft All-Weather Operations Research Program. The system is based on state-of-of-the-art X-band radar technology and digital processing techniques. The bLS airborne hardware consists of an X-band receiver and a small micropreocessor, installed in conjunction wht the aircraft instrument landing system (ILS) receiver. The microprocessor analyzes the X-band, BLS pulses and outputs ILS-compatible localizer and glide slope signals. Range information is obtained using an on-board weather/mapping radar in conjunction with the BLS. The ground station is an inexpensive, portable unit; it weighs less than 70 lb and can be quickly deployed at a landing site. Results from the flight-test program show that the BLS has a significant potential for providing rotorcaraft with low-cost, precision instrument approach capability in remote areas

    Development of a portable precision landing system

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    A portable, tactical approach guidance (PTAG) system, based on a novel, X-band, precision approach concept, was developed and flight tested as a part of NASA's Rotorcraft All-Weather Operations Research Program. The system is based on state-of-the-art X-band technology and digital processing techniques. The PTAG airborne hardware consists of an X-band receiver and a small microprocessor installed in conjunction with the aircraft instrument landing system (ILS) receiver. The microprocessor analyzes the X-band, PTAG pulses and outputs ILS compatible localizer and glide slope signals. The ground stations are inexpensive, portable units, each weighing less than 85 lb, including battery, that can be quickly deployed at a landing site. Results from the flight test program show that PTAG has a significant potential for providing tactical aircraft with low cost, portable, precision instrument approach capability

    A rocket-borne pulse-height analyzer for energetic particle measurements

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    The pulse-height analyzer basically resembles a time-sharing multiplexing data-acquisition system which acquires analog data (from energetic particle spectrometers) and converts them into digital code. The PHA simultaneously acquires pulse-height information from the analog signals of the four input channels and sequentially multiplexes the digitized data to a microprocessor. The PHA together with the microprocessor form an on-board real-time data-manipulation system. The system processes data obtained during the rocket flight and reduces the amount of data to be sent back to the ground station. Consequently the data-reduction process for the rocket experiments is speeded up. By using a time-sharing technique, the throughput rate of the microprocessor is increased. Moreover, data from several particle spectrometers are manipulated to share one information channel; consequently, the TM capacity is increased

    Advanced CO2 removal process control and monitor instrumentation development

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    A progam to evaluate, design and demonstrate major advances in control and monitor instrumentation was undertaken. A carbon dioxide removal process, one whose maturity level makes it a prime candidate for early flight demonstration was investigated. The instrumentation design incorporates features which are compatible with anticipated flight requirements. Current electronics technology and projected advances are included. In addition, the program established commonality of components for all advanced life support subsystems. It was concluded from the studies and design activities conducted under this program that the next generation of instrumentation will be greatly smaller than the prior one. Not only physical size but weight, power and heat rejection requirements were reduced in the range of 80 to 85% from the former level of research and development instrumentation. Using a microprocessor based computer, a standard computer bus structure and nonvolatile memory, improved fabrication techniques and aerospace packaging this instrumentation will greatly enhance overall reliability and total system availability

    Development and flight test of an X-band precision approach concept for remote-area rotorcraft operations

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    A novel airborne radar-based precision approach concept was developed and flight tested as a part of NASA's Rotorcraft All-Weather Operations Research Program. A demonstration, transponder-based beacon landing system (BLS), incorporating state-of-the-art X-band radar technology and digital processing techniques, was built and flight tested to demonstrate the concept feasibility. The BLS airborne hardware consists of an add-on microprocessor, installed in conjunction with the aircraft weather/mapping radar, which analyzes the radar beacon receiver returns and determines range, localizer deviation, and glide slope deviation. The ground station is an inexpensive, portable unit which can be quickly deployed at a landing site. Results from the flight test program show that the BLS concept has a significant potential for providing rotorcraft with low-cost, precision, instrument approach capability in remote areas
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