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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Digital Grid Twin–Direct Communication Scheme Test Bed for Assessing Relay-to-Relay Radio Antenna and Optical Fiber Performance and Misoperations

This study introduces a novel “Digital Grid Twin–Direct Communication Scheme” test bed. This advanced platform evaluates point-to-point communication between transmitter and receiver relays with optical fiber and radio omnidirectional antenna systems, implemented at the Advanced Protection lab in the Grid Research Innovation and Development Center at Oak Ridge National Laboratory. The increased diversity of energy sources has led to more protective relay misoperations. In North America, microgrid protection schemes now use point-to-point communication along distribution lines between relays to implement advanced logic in nonradial grids that include both high- and low-inertia generators. This trend challenges utilities to minimize misoperations while ensuring rapid fault clearance and accurate selectivity coordination between primary and backup relays. This study assesses relay-to-relay communication schemes by introducing an advanced testing platform based on a digital grid twin protection test bed using a synchronized time source system. The platform evaluates the communication system using radio antennas or optical fiber links by integrating protective relays that operate breakers within the digital twin and record relay events and communication signals. In the experiments, transmitter and receiver relays were configured with inverse time overcurrent and breaker trip detection logic to assess the total time of the communication protection schemes based on the sum of the relay protection element operating time, radio latency, propagation delay, baud rate delay, and relay processing time. These delays were derived from recorded relay events and communication signals from the interface of a real-time simulator set as a digital grid twin. The test bed successfully simulated various electrical faults along a distribution line while ensuring effective and reliable point-to-point communication between transmitter and receiver relays. The radio antenna communication system exhibited latency because of the radio. This latency depends on the baud rate setting and type of radio application; in general, the higher the baud rate, the lower the radio latency. The measured radio latency (for Mirrored Bits with an encryption card at 9,600 bps) was about 9–10 ms. Additionally, calculated propagation delay per mile for radio antennas and optical fiber was 5.36 µs/mi and 8.04 µs/mi, respectively. Optical fiber communication did not demonstrate radio latency. Instead, the protection element operating time depends mainly on the protection logic function set in the relay, and the relay processing time depends on the processing rate of the relay in samples per power system cycle.

24 POWER TRANSMISSION AND DISTRIBUTION↗
NASA NTRS2013

Advanced Strategic and Tactical Relay Request Management for the Mars Relay Operations Service

This software provides a new set of capabilities for the Mars Relay Operations Service (MaROS) in support of Strategic and Tactical relay, including a highly interactive relay request Web user interface, mission control over relay planning time periods, and mission management of allowed strategic vs. tactical request parameters. Together, these new capabilities expand the scope of the system to include all elements critical for Tactical relay operations. Planning of replay activities spans a time period that is split into two distinct phases. The first phase is called Strategic, which begins at the time that relay opportunities are identified, and concludes at the point that the orbiter generates the flight sequences for on board execution. Any relay request changes from this point on are called Tactical. Tactical requests, otherwise called Orbit - er Relay State Changes (ORSC), are highly restricted in terms of what types of changes can be made, and the types of parameters that can be changed may differ from one orbiter to the next. For example, one orbiter may be able to delay the start of a relay request, while another may not. The legacy approach to ORSC management involves exchanges of e-mail with "requests for change" and "acknowledgement of approval," with no other tracking of changes outside of e-mail folders. MaROS Phases 1 and 2 provided the infrastructure for strategic relay for all supported missions. This new version, 3.0, introduces several capabilities that fully expand the scope of the system to include tactical relay. One new feature allows orbiter users to manage and "lock" Planning Periods, which allows the orbiter team to formalize the changeover from Strategic to Tactical operations. Another major feature allows users to interactively submit tactical request changes via a Web user interface. A third new feature allows orbiter missions to specify allowed tactical updates, which are automatically incorporated into the tactical change process. This software update is significant in that it provides the only centralized service for tactical request management available for relay missions.

Allard, Daniel A.↗
NASA NTRS2012

Relay Support for the Mars Science Laboratory and the Coming Decade of Mars Relay Network Evolution

In the past decade, an evolving network of Mars relay orbiters has provided telecommunication relay services to the Mars Exploration Rovers, Spirit and Opportunity, and to the Mars Phoenix Lander, enabling high-bandwidth, energy-efficient data transfer and greatly increasing the volume of science data that can be returned from the Martian surface, compared to conventional direct-to-Earth links. The current relay network, consisting of NASA's Odyssey and Mars Reconnaissance Orbiter and augmented by ESA's Mars Express Orbiter, stands ready to support the Mars Science Laboratory, scheduled to arrive at Mars on Aug 6, 2012, with new capabilities enabled by the Electra and Electra-Lite transceivers carried by MRO and MSL, respectively. The MAVEN orbiter, planned for launch in 2013, and the ExoMars/Trace Gas Orbiter, planned for launch in 2016, will replenish the on-orbit relay network as the current orbiter approach their end of life. Currently planned support scenarios for this future relay network include an ESA EDL Demonstrator Module deployed by the 2016 ExoMars/TGO orbiter, and the 2018 NASA/ESA Joint Rover, representing the first step in a multimission Mars Sample Return campaign.

MAVEN↗
NASA NTRS2015

The Laser Communications Relay and the Path to the Next Generation Near Earth Relay

NASA Goddard Space Flight Center is currently developing the Laser Communications Relay Demonstration (LCRD) as a Path to the Next Generation Near Earth Space Communication Network. The current NASA Space Network or Tracking and Data Relay Satellite System is comprised of a constellation of Tracking and Data Relay Satellites (TDRS) in geosynchronous orbit and associated ground stations and operation centers. NASA is currently targeting a next generation of relay capability on orbit in the 2025 timeframe.

Laser Communication Relay Demonstration↗
NASA NTRSDate not supplied

Framework for NASA Space Relay Satellite Services over the Next Decade: Space Relay Partnership and Services Study

The United States National Space Policy provides guidance and directives for U.S. Government agencies to purchase commercial space services and capabilities to the maximum extent practical. In alignment with this guidance, the anticipated initial NASA near-Earth space relay operating capability over the next decade will be comprised of the existing NASA-owned Space Network infrastructure supplemented with commercially-owned and -provided relay satellites and their associated ground stations. NASA awarded contracts to eight study vendors in May 2019 to investigate the feasibility of applying commercial services concepts to the NASA user mission community. The studies, managed by NASA Glenn Research Center, detailed ten study topic areas. NASA completed the analysis and synthesis of these eight industry studies and other relevant information. The responses from the study vendors indicated a strong interest in providing commercial services to NASA missions, and included a wide range of proposed architectures and demonstration ideas. Overall, the responses indicated that a mature and healthy competitive environment exists across a broad spectrum of industry to deliver high-rate space relay services in the next three to five years. This paper will present an overview of the study, analysis and synthesis processes along with common themes and conclusions, and provide next steps and recommendations. The results of this study serve as a foundation for ongoing efforts to acquire interoperable space relay services for NASA missions from multiple commercial service providers.

Eric Knoblock↗
NASA NTRSDate not supplied

Framework for NASA Space Relay Satellite Services over the Next Decade: Space Relay Partnership and Services Study

The United States National Space Policy provides guidance and directives for U.S. Government agencies to purchase commercial space services and capabilities to the maximum extent practical. In alignment with this guidance, the anticipated initial NASA near-Earth space relay operating capability over the next decade will be comprised of the existing NASA-owned Space Network infrastructure supplemented with commercially-owned and -provided relay satellites and their associated ground stations. NASA awarded contracts to eight study vendors in May 2019 to investigate the feasibility of applying commercial services concepts to the NASA user mission community. The studies, managed by NASA Glenn Research Center, detailed ten study topic areas. NASA completed the analysis and synthesis of these eight industry studies and other relevant information. The responses from the study vendors indicated a strong interest in providing commercial services to NASA missions, and included a wide range of proposed architectures and demonstration ideas. Overall, the responses indicated that a mature and healthy competitive environment exists across a broad spectrum of industry to deliver high-rate space relay services in the next three to five years. This paper will present an overview of the study, analysis and synthesis processes along with common themes and conclusions, and provide next steps and recommendations. The results of this study serve as a foundation for ongoing efforts to acquire interoperable space relay services for NASA missions from multiple commercial service providers.

Eric Knoblock↗
NASA NTRSDate not supplied

Insights and Observations from Operating a Geostationary Laser Communication Relay Mission: Operational Lessons from NASA’s Laser Communications Relay Demonstration (LCRD) and Associated Optical Ground Stations (OGSs)

The NASA Laser Communications Relay Demonstration (LCRD) has operated on orbit for the last two years. The LCRD Mission consists of a geostationary payload and two optical ground stations. This technology demonstration mission is NASA’s first two-way, end-to-end optical communications relay. LCRD has performed an extensive experiment campaign to analyze laser communication performance for extended operations. This paper discusses various lessons learned while operating the optical relay mission from early commissioning through two years of operation. Before launch, engineers and operators performed analyses to generate operational procedures based on expected LCRD performance. However, only operation on orbit can supply actual performance data. Additional topics covered in this paper include pre-launch and commissioning testing, ephemeris generation and cadence, environmental configurations, and accommodation concerns. The addition of Integrated Laser Communications Relay Demonstration Low Earth Orbit User Modem and Amplifier Terminal (ILLUMA-T) to the optical network supplemented the LCRD team’s operational experiences and enabled them to garner new lessons learned. The authors of this paper include day-to-day flight leads who consulted with on-console operators, engineers, and subject matter experts analyzing data and experiment results to gather the lessons learned described in this paper. LCRD is a joint project involving NASA Goddard Space Flight Center (GSFC), the California Institute of Technology Jet Propulsion Laboratory (JPL), and Massachusetts Institute of Technology Lincoln Laboratory (MIT LL).

Lessons Learned↗
NASA NTRS1994

Optimum satellite relay positions with application to a TDRS-1 Indian Ocean relay

An Indian Ocean satellite relay is examined. The relay satellite position is optimized by minimizing the sum of downlink and satellite to satellite link losses. Osculating orbital elements are used for fast intensive orbital computation. Integrated Van Vleck gaseous attenuation and a Crane rain model are used for downlink attenuation. Circular polarization losses on the satellite to satellite link are found dynamically. Space to ground link antenna pointing losses are included as a function of yaw ans spacecraft limits. Relay satellite positions between 90 to 100 degrees East are found attractive for further study.

Jackson, A. H.↗
NASA NTRS2012

Relay Support for the Mars Science Laboratory and the Coming Decade of Mars Relay Network Evolution

Mars Relay Network is prepared to support MSL: a) ODY/MRO/MEX will all provide critical event comm support during EDL. b) New Electra/Electra-Lite capabilities on the MSL-MRO link will support >250 Mb/sol MSL data return. 2013 MAVEN orbiter will replenish on-orbit relay infrastructure as prior orbiters approach end-of-life. While NASA has withdrawn from the 2016 EMTGO and 2018 Joint Rover missions, analysis of the potential link shows a path to Gbit/sol relay capability 2012.

critical event telemetry↗
NASA NTRS2018

Next Generation Relay Services at Mars via an International Relay Network

Nearly all data acquired by vehicles on the surface of Mars are returned to Earth via Mars orbiters – more than 1.7 terabits so far. Successful communication between the various spacecraft is achieved via the careful implementation of internationally recognized CCSDS telecommunications protocols and the use of planning and coordination services provided by NASA’s Mars Program Office and the Multimission Ground Systems and Services (MGSS) Program at the Jet Propulsion Laboratory in Pasadena, CA. This modern Mars relay network has evolved since its inception in 2004 with the addition and loss of several missions, but it has fundamentally remained unchanged. Ground interfaces between the various spacecrafts’ mission operations centers on Earth remain largely unique for each participant, each mission maintains its own interfaces with deep space communications networks (e.g. DSN, ESTRACK), which are similar but still unique; and relay sessions at Mars require careful ground planning, coordination, and implementation. This paper will discuss the existing architecture and consider how several technologies may be applied to the next generation of relay services at Mars. Ultimately, these are expected to lead to the implementation of a delay and disruption tolerant network at Mars, a precursor to becoming a major element in an emerging Solar System Internet.

Edwards, Charles D. Jr↗
NASA NTRSDate not supplied

Lunar Surface Relay - Mobile: Concept to Provide Relay Links to Surface Assets

At the request of NASA’s Space Communication and Navigation (SCaN) program, the Glenn Research Center’s (GRC) Compass concurrent engineering team developed a conceptual design of a Lunar Surface Relay- Mobile (LSR-M) system to provide a variety of surface and relay communication links in support of future Artemis sorties. The team determined that a mobile asset, with its ability to relocate to support a variety of surface sites and leverage more hospitable winter locations on the lunar south pole, would be of particular use in the architecture. Following the design of a solar array and battery powered baseline case, a quick look design further investigated adding a multi-mission radioisotope thermoelectric generator (MMRTG) to the system to reduce battery requirements to survive the lunar night and remove the need to relocate to favorable night locations during the lunar winter.

Lunar Surface Relay↗
NASA NTRS2017

Laser Communications Relay Demonstration (LCRD) Update and the Path Towards Optical Relay Operations

This paper provides a concept for an evolution of NASA's optical communications near Earth relay architecture. NASA's Laser Communications Relay Demonstration (LCRD), a joint project between NASA's Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory - California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MIT LL). LCRD will provide a minimum of two years of high data rate optical communications service experiments in geosynchronous orbit (GEO), following launch in 2019. This paper will provide an update of the LCRD mission status and planned capabilities and experiments, followed by a discussion of the path from LCRD to operational network capabilities.

Space Communications↗
NASA NTRS2017

Laser Communications Relay Demonstration (LCRD) Update and the Path Towards Optical Relay Operations

This Presentation provides a concept for an evolution of NASAs optical communications near Earth relay architecture. NASA's Laser Communications Relay Demonstration (LCRD), a joint project between NASAs Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory - California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MIT LL). LCRD will provide a minimum of two years of high data rate optical communications service experiments in geosynchronous orbit (GEO), following launch in 2019. This paper will provide an update of the LCRD mission status and planned capabilities and experiments, followed by a discussion of the path from LCRD to operational network capabilities.

Space Communications↗
DOE OSTI2026

Digital Grid Twin–Direct Communication Scheme Test Bed for Assessing Relay-to-Relay Radio Antenna and Optical Fiber Performance and Misoperations

This study introduces a novel “Digital Grid Twin–Direct Communication Scheme” test bed. This advanced platform evaluates point-to-point communication between transmitter and receiver relays with optical fiber and radio omnidirectional antenna systems, implemented at the Advanced Protection lab in the Grid Research Innovation and Development Center at Oak Ridge National Laboratory.

99 GENERAL AND MISCELLANEOUS↗