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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

IMACCS: A Progress Report on NASA/GSFC's COTS-Based Ground Data Systems, and Their Extension into New Domains

Scheidker, E. J., Pendley, R. D., Rashkin, R. M., Weking, R. D., Cruse, B. G., Bracken, M. A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The Integrated Monitoring, Analysis, and Control COTS System (IMACCS), a system providing real time satellite command and telemetry support, orbit and attitude determination, events prediction, and data trending, was implemented in 90 days at NASA Goddard Space Flight Center (GSFC) in 1995. This paper describes upgrades made to the original commercial, off-the-shelf (COTS)-based prototype. These upgrades include automation capability and spacecraft Integration and Testing (I&T) capability. A further extension to the prototype is the establishment of a direct RF interface to a spacecraft. As with the original prototype, all of these enhancements required lower staffing levels and reduced schedules compared to custom system development approaches. The team's approach to system development, including taking advantage of COTS and legacy software, is also described.
182

A COMMERCIAL CCSDS TELECOMMAND PROCESSOR

Shi, Jeff, Flanagan, Barbara, Mao, Tony, Sanford, Terry 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / After a slow start, the CCSDS Telecommand Recommendation is finally being embraced by a large number of NASA, ESA and NASDA space missions. Even some commercial satellites are exploring the possibility of using this advanced protocol. The CCSDS Telecommand is a closed-loop space communication protocol that offers its users a guaranteed data delivery service, which is essential for the satellite control operations. This paper describes a commercial product that supports the CCSDS Telecommand protocol. This product provides Telecommand uplink segmentation, transfer, coding and physical layer services and Command Operations Procedures (COP). Optionally, it provides corresponding functions at the receiving end for command link verification.
183

NEAR REAL-TIME TELEMETRY UTILIZING SATELLITE COMMUNICATIONS

Maurer, Ricky L. 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / Satellite transmission systems have proven themselves very effective in a variety of applications. One such application is the transmission of telemetry (TM) data and associated information in a near real-time environment. This paper describes the satellite data relay system currently utilized by the Telemetry Data Center at Patuxent River, Maryland and the corresponding remote receiving site, and discusses the performance of this system.
184

THE PHILLIPS LABORATORY’S MOBILE GROUND TRACKING STATION (MGTS)

Stone, Christopher E., Flint, Keith D., Mathis, Gregory P. 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / Phillips Laboratory's Space Experiments Directorate (PL/SX) is operating and upgrading the laboratory's premier transportable satellite tracking station, the Mobile Ground Tracking Station (MGTS) program. MGTS supports orbital, suborbital, and aircraft missions as a range system capable of processing and recording multiple data streams. MGTS receives, processes, displays, and records satellite state-of-health data, infrared images in a variety of wavelengths, video data, and state vector solutions based on IR returns from the Miniature Sensor Technology Integration (MSTI) satellite program. The program has began in 1990 under BMDO sponsorship, with the intent to supplement existing test ranges with more flexibility in range operations. Wyle Laboratories and Systems Engineering and Management Company (SEMCO) provided the technical expertise necessary to create the first MGTS system. Autonomy and off-road capability were critical design factors, since some of the operations envisioned require deployment to remote or hostile field locations. Since inception, MGTS has supported the Lightweight Exo-Atmospheric Projectile (LEAP) sub-orbital missions, the MSTI satellite program, and Air Force wargame demonstrations. In pursuit of these missions, MGTS has deployed to White Sands Missile Range (WSMR), NM; Air Force Flight Test Center (AFFTC), Edwards AFB, CA; Vandenberg AFB, CA; Falcon AFB, CO; and NASA's Wallops Island Flight Facility, VA, to receive critical mission telemetry data conforming to both IRIG and SGLS standards. This paper will describe the evolution of the MGTS program, current hardware configurations and past and future mission scenarios for the MGTS team.
185

TT&C SYSTEM FOR NASDA NEW GROUND NETWORK

Sarai, Hirohit, Izumi, Kazushige, Fujiwara, Tomohiro, Sutton, Jerry, Meyers, Thomas, Willis, James 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In response to a NASDA decision to upgrade their satellite ground network (GN) to provide worldwide coverage as well as interoperability with other agencies, MELCO has assembled remote ground stations that include the L-3 Communications Telemetry & Instrumentation (L-3 T&I) NETstar 20001 TT&C system. Software developed by Mitsubishi Electric Corporation (MELCO) controls a variety of COTS products in the remote stations, including the L-3 T&I system. L-3 T&I’s TT&C system provides modem services, high accuracy ranging, Doppler compensation, command verification, and CCSDS protocol processing for a wide range of LEO/MEO/GEO satellites.
186

An Expert System for Satellite Control

Pazzani, Michael, Brindle, Anne 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1985 / Riviera Hotel, Las Vegas, Nevada / As on-board satellite systems develop increased sophistication and autonomous capabilities, failures become fewer, but the diagnosis of the remaining failures becomes more complex. In addition, autonomy requirements for space vehicles are being issued along with requirements for reduced staffing of ground stations. Thus successful groundbased fault handling in the future will require greatly increased automation of fault detection and diagnosis. This paper investigates the use of an expert system as a ground system component for diagnosis. The diagnostic cycle of the system is presented, along with requirements for its knowledge base. The results of implementing the design to diagnose part of a satellite attitude control system are given. Knowledge acquisition for this problem centered on the generation and analysis of terminal displays of telemetry which look much like strip charts. Correct diagnosis by the expert system derived from the use of extensive telemetry analysis, operations and satellite status databases, and satellite modeling.
187

Statistical inversion of surface parameters from ATSR-2 satellite observations

Fletcher, R. P. January 1999 (has links)
No description available.
188

Mass modelling in X-/#gamma#-ray astronomy

Ferguson, Colin January 2000 (has links)
No description available.
189

Real time kinematic GPS and multipath : characterisation and improved least squares modelling

Barnes, Joel B. January 2000 (has links)
No description available.
190

Regional approach to wide area DGPS

Aquino, Marcio Henrique Oliveira de January 1999 (has links)
No description available.

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