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NASA NTRS2014

Optical Communications Telescope Laboratory (OCTL) Support of Space to Ground Link Demonstrations

The NASA/JPL Optical Communication Telescope Laboratory (OCTL) was built for dedicated research and development toward supporting free-space laser communications from space. Recently, the OCTL telescope was used to support the Lunar Laser Communication Demonstration (LLCD) from the Lunar Atmospheric Dust Environment Explorer (LADEE) spacecraft and is planned for use with the upcoming Optical Payload for Lasercomm Science (OPALS) demonstration from the International Space Station (ISS). The use of OCTL to support these demonstrations is discussed in this report. The discussion will feed forward to ongoing and future space-to-ground laser communications as it advances toward becoming an operational capability.

ground operations↗

NASA NTRS2016

Bandwidth-Efficient Communication through 225 MHz Ka-band Relay Satellite Channel

The communications and navigation space infrastructure of the National Aeronautics and Space Administration (NASA) consists of a constellation of relay satellites (called Tracking and Data Relay Satellites (TDRS)) and a global set of ground stations to receive and deliver data to researchers around the world from mission spacecraft throughout the solar system. Planning is underway to enhance and transform the infrastructure over the coming decade. Key to the upgrade will be the simultaneous and efficient use of relay transponders to minimize cost and operations while supporting science and exploration spacecraft. Efficient use of transponders necessitates bandwidth efficient communications to best use and maximize data throughput within the allocated spectrum. Experiments conducted with NASA's Space Communication and Navigation (SCaN) Testbed on the International Space Station provides a unique opportunity to evaluate advanced communication techniques, such as bandwidth-efficient modulations, in an operational flight system. Demonstrations of these new techniques in realistic flight conditions provides critical experience and reduces the risk of using these techniques in future missions. Efficient use of spectrum is enabled by using high-order modulations coupled with efficient forward error correction codes. This paper presents a high-rate, bandwidth-efficient waveform operating over the 225 MHz Ka-band service of the TDRS System (TDRSS). The testing explores the application of Gaussian Minimum Shift Keying (GMSK), 2/4/8-phase shift keying (PSK) and 16/32- amplitude PSK (APSK) providing over three bits-per-second-per-Hertz (3 b/s/Hz) modulation combined with various LDPC encoding rates to maximize through- put. With a symbol rate of 200 M-band, coded data rates of 1000 Mbps were tested in the laboratory and up to 800 Mbps over the TDRS 225 MHz channel. This paper will present on the high-rate waveform design, channel characteristics, performance results, compensation techniques for filtering and equalization, and architecture considerations going forward for efficient use of NASA's infrastructure.

transmitters receivers↗

NASA NTRS2016

Bandwidth-Efficient Communication through 225 MHz Ka-band Relay Satellite Channel

The communications and navigation space infrastructure of the National Aeronautics and Space Administration (NASA) consists of a constellation of relay satellites (called Tracking and Data Relay Satellites (TDRS)) and a global set of ground stations to receive and deliver data to researchers around the world from mission spacecraft throughout the solar system. Planning is underway to enhance and transform the infrastructure over the coming decade. Key to the upgrade will be the simultaneous and efficient use of relay transponders to minimize cost and operations while supporting science and exploration spacecraft. Efficient use of transponders necessitates bandwidth efficient communications to best use and maximize data throughput within the allocated spectrum. Experiments conducted with NASA's Space Communication and Navigation (SCaN) Testbed on the International Space Station provides a unique opportunity to evaluate advanced communication techniques, such as bandwidth-efficient modulations, in an operational flight system. Demonstrations of these new techniques in realistic flight conditions provides critical experience and reduces the risk of using these techniques in future missions. Efficient use of spectrum is enabled by using high-order modulations coupled with efficient forward error correction codes. This paper presents a high-rate, bandwidth-efficient waveform operating over the 225 MHz Ka-band service of the TDRS System (TDRSS). The testing explores the application of Gaussian Minimum Shift Keying (GMSK), 248-phase shift keying (PSK) and 1632- amplitude PSK (APSK) providing over three bits-per-second-per-Hertz (3 bsHz) modulation combined with various LDPC encoding rates to maximize throughput. With a symbol rate of 200 Mbaud, coded data rates of 1000 Mbps were tested in the laboratory and up to 800 Mbps over the TDRS 225 MHz channel. This paper will present on the high-rate waveform design, channel characteristics, performance results, compensation techniques for filtering and equalization, and architecture considerations going forward for efficient use of NASA's infrastructure.

space communications↗

NASA NTRS2017

Secure Network-Centric Aviation Communication (SNAC)

The existing National Airspace System (NAS) communications capabilities are largely unsecured, are not designed for efficient use of spectrum and collectively are not capable of servicing the future needs of the NAS with the inclusion of new operators in Unmanned Aviation Systems (UAS) or On Demand Mobility (ODM). SNAC will provide a ubiquitous secure, network-based communications architecture that will provide new service capabilities and allow for the migration of current communications to SNAC over time. The necessary change in communication technologies to digital domains will allow for the adoption of security mechanisms, sharing of link technologies, large increase in spectrum utilization, new forms of resilience and redundancy and the possibly of spectrum reuse. SNAC consists of a long term open architectural approach with increasingly capable designs used to steer research and development and enable operating capabilities that run in parallel with current NAS systems.

Communications↗

NASA NTRS2017

An Update on the CCSDS Optical Communications Working Group

International space agencies around the world are currently developing optical communication systems for Near Earth and Deep Space applications for both robotic and human rated spacecraft. These applications include both links between spacecraft and links between spacecraft and ground. The Interagency Operation Advisory Group (IOAG) has stated that there is a strong business case for international cross support of spacecraft optical links. It further concluded that in order to enable cross support the links must be standardized. This paper will overview the history and structure of the space communications international standards body, the Consultative Committee for Space Data Systems (CCSDS), that will develop the standards and provide an update on the proceedings of the Optical Communications Working Group within CCSDS. This paper will also describe the set of optical communications standards being developed and outline some of the issues that must be addressed in the next few years. The paper will address in particular the ongoing work on application scenarios for deep space to ground called High Photon Efficiency, for LEO to ground called Low Complexity, for inter-satellite and near Earth to ground called High Data Rate, as well as associated atmospheric measurement techniques and link operations concepts.

Laser and Optical Communications↗

NASA NTRS2017

Omnidirectional Inter-Satellite Optical Communicator (ISOC)

The objective of the Omnidirectional Inter-Satellite Optical Communicator (ISOC) project is to design a compact, lightweight,and energy efficient communicator module for use between satellites in space. This module will achieve continuous optical communication, with simultaneous data transmission and reception, at up to1 gigabit per second (Gbits) data rates for small spacecraft separated by up to 200 kilometers (kms). To achieve this goal,a data communicator with full spherical coverage field of view (FOV) needs to be designed. The proposed ISOC is a dodecahedron geometric array of chipscale, microelectromechanical systems (MEMS) based gimbal-less scanning mirrors that provide adjustable beam pointing and spherical FOV coverage for uninterrupted data transmission between several small spacecraft at arbitrary relative positions. This design eliminates known pointing issues and hence allows accurate direction of arrival calculations.Moreover, the proposed approach will enable data relaying between multiple satellites, and enable relative navigation control.

Inter-small satellite communication↗

NASA NTRS2018

Update on NASA's Laser Communications Relay Demonstration Project

This paper provides an update on NASA's Laser Communications Relay Demonstration Project (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 services to demonstrate a concept of operations for future mission critical Earth relay satellites. LCRD is expected to launch in June 2019 and demonstrate how optical communications can meet NASA's growing need for higher data rates, or for the same data rate provided by a comparable RF system, how it enables lower power, lower mass communications systems on user spacecraft. In addition, LCRD's architecture will allow it to serve as a testbed in space for the development of additional symbol coding, link and network layer protocols, etc. LCRD's mission and architecture has slowly evolved since the project first started and this paper will provide an update of LCRD and planned capabilities and experiments.

Optical Communications↗

NASA NTRSDate not supplied

NASA Lunar Exploration – Gateway’s Power and Propulsion Element Communications Links

As a key part of NASA’s Artemis program to return to the moon, the Lunar Gateway will provide a platform for staging lunar missions, for gaining experience in operations beyond earth orbit, and for creating sustainable infrastructure. Of specific interest, the Lunar Gateway will provide communications support to landers, orbiters, and surface systems, including in the South Polar Region where direct line of sight (LOS) to Earth is limited or non-existent. A foundational segment of the Gateway is the Power and Propulsion Element (PPE), which will carry: solar arrays to provide power to the Gateway; electric propulsion to maintain the Gateway in its operational orbit; and communication links between the Earth and Gateway, the Moon and Gateway, and relays from the Moon to the Earth. PPE Communication Links include an X-band link to Earth for Command, Ranging, and Telemetry (CR&T), which also carries low to medium rate data; a Ka-band Direct to Earth(DTE) link for high rate data transmissions; and a Ka-band Lunar link for high data rate connections to lunar systems. This paper describes the PPE communication links from a technical perspective. Other Gateway links supported by other modules are outside the scope of this paper.

ARTEMIS↗

NASA NTRSDate not supplied

SCaN: Space Communication and Navigation - 5G in Space

NASA’s Space Communications and Navigation (SCaN) program office builds, operates, and maintains NASA’s two primary communications networks – the Near Space Network and the Deep Space Network. These networks allow spacecraft near and far to send critical tracking, telemetry, command, and science data to Earth. SCaN also investigates new communications and navigation technologies so that these networks can support advanced missions. SCaN’s Commercialization, Innovation, and Synergies (CIS) office is dedicated to creating robust partnerships with industry, academia, and other government agencies to advance communications and navigation capabilities.

5G↗

NASA NTRS2020

Workshop on Space Quantum Communications and Networks

NASA’s Space Communications and Navigation (SCaN) program and the National Institute of Science and Technology (NIST) co-sponsored a two-day workshop in January 2020 on space quantum communications and networks. The workshop was hosted by the Space Sciences Laboratory of the University of California, Berkeley. About 70 invited technical and program leaders from academia, industry, and government agencies defined science goals and technology requirements for a future NASA “quantum mission” that is fully aligned with the National Quantum Initiative (NQI) vision for a space-ground quantum network. This NQI vision is also a strategic milestone in SCaN’s plans for NASA’s space-based quantum communications and networks. The overall technical objectives of the Workshop were to (i) critically evaluate various mission design concepts, (ii) converge on a small subset of quantum communication and networking experiments suitable for space applications, and (iii) identify key technology gaps and promote new and emerging technologies to enable NASA’s “quantum mission” within a 5-year horizon.

quantum communications↗

NASA NTRSDate not supplied

Enabling Communication Between Astronauts and Ground Teams for Space Exploration Missions

Over the last four years, Playbook’s Mission Log has evolved to become an enabling capability for analog missions that simulate deep space, exploration missions with communication transmission latency. Playbook is a planning and execution web-application for mission operations, aggregating multiple sources of information for astronauts to execute the mission in one place: timeline, procedures, chat interface. Playbook’s Mission Log provides a multimedia chat software interface with unique features and functionalities that support asynchronous communication between analog astronauts and ground support teams. This paper describes the iterative design the Mission Log has undergone based on user observations and solicited feedback. Key features include indicators that help users cope with asynchronous communication as well as aids that assist teams coordinate work. Future work and capabilities are outlined, which build upon the increased use of the Mission Log as a communication and coordination tool for space exploration.

communication↗

NASA NTRSDate not supplied

Enhancing Autonomous Satellite Communication Systems with Weather-Aware Scheduling and Reconfiguration

NASA currently provides communication support to over 100 satellite missions, and the agency is driving developments in Ka-band communications and network management automation to support additional future missions. At Ka-band frequencies, rain can degrade a communication link by more than 10 dB, which may be mitigated by agile scheduling and data rate control. We present a weather forecasting module for Ka-band communications that is intended to be used in an autonomous network management service that employs machine-to-machine scheduling systems for dynamic user access opportunities. Our forecasting module (NIMBUS) runs on AWS Cloud, consumes the freely and publicly available NOAA MRMS precipitation rate dataset (1km x 1km x 2-min), produces 30-minute Nowcasts using the pySTEPS algorithm, and publishes high level ground station specific link quality predictions. We evaluate two potential NIMBUS outputs, a binary classifier that predicts rain attenuation greater than 3 dB and a rain attenuation estimator, and we backtest these outputs using one year of power measurement data collected from observations of the geostationary ANIK F2 satellite’s Ka-band beacon. We report, with a 30-minute lead time, a binary classifier accuracy of 84% and an estimator RMSE of 1.67 dB. Additionally, we discuss how the NIMBUS module could be incorporated into a user-initiated service framework to enable weather-aware scheduling and reconfiguration. Operating a static link budget with minimal link margin can increase network operation costs by creating additional scheduling tasks due to failed packets, which may require human intervention and/or lead to inefficient asset utilization. The proposed system aims to increase throughput by reducing link margin, while mitigating increases in network operations costs by leveraging autonomous machine-to-machine scheduling, shortened prediction lead times, and advances in precipitation Nowcasting.

satellite communications↗

NASA NTRSDate not supplied

Insights and Observations From Operating A Laser Communication Terminal on the International Space Station (ISS)

The Integrated Laser Communication Relay Demonstration (LCRD) Low Earth Orbit User Modem and Amplifier Terminal (ILLUMA-T) is the first user platform for NASA’s first laser communication relay, LCRD. ILLUMA-T is hosted on the International Space Station (ISS) as an external payload of the Japanese Experiment Module – Exposed Facility (JEM-EF) situated in slot 3. The LCRD payload is hosted on the STPSat-6 spacecraft, which orbits Earth in a geostationary orbit at position 112 W. The ILLUMA-T-to-LCRD system provides a bidirectional, space-to-ground laser communication relay link transferring data up to 1.2 Gbps utilizing two optical ground stations (OGS), OGS-1 in California and OGS-2 in Hawai’i. This paper describes lessons learned from operating the ILLUMA-T system and examines topics such as the end-to-end system availability, predictive versus actual ephemeris, acquisition adjustments, modem timing and handshaking, the terminal’s physical placement and accommodations, and experiment development, execution, and analysis. The authors of this paper operate both the LCRD and ILLUMA-T laser terminals on a daily basis including pass planning, procedure execution, acquisition analysis, and real-time terminal commanding and telemetry monitoring. 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). The ILLUMA-T payload is managed by NASA GSFC in Greenbelt, Maryland whose partners include the ISS program office at NASA’s Johnson Space Center (JSC) in Houston, Texas; the Huntsville Operations Support Center (HOSC) at Marshall Space Flight Center (MSFC) in Huntsville, Alabama; the Glenn Research Center (GRC) in Cleveland, Ohio; and the MIT LL in Lexington, Massachusetts. ILLUMA-T is funded by the Space Communications and Navigation (SCaN) Program at NASA Headquarters in Washington, D.C.

Laser Communications↗

DOE OSTI2021

Impact of DER Communication Delay in AGC: Cyber-Physical Dynamic Co-Simulation: Preprint

Distributed energy resource (DER) frequency regulations are promising technologies for future grid operation. Unlike conventional generators, DERs might require open communication networks to exchange signals with control centers, possibly through DER aggregators; therefore, the impacts of the communication variations including the latency on the system frequency stability need to be investigated. This paper develops a cyber-physical dynamic simulation (CPDS) model based on the Hierarchical Engine for Large-Scale Co-Simulation (HELICS) to evaluate the impact of the communication variations, such as delays in DER frequency regulations. The feasible delay range can be obtained under different AGC parameter settings. The results show that the risk of instability generally increases with the communication delay and that the difference of AGC provided from DER and conventional generation units should be recognized when designing frequency regulation controllers.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2023

Reliable and Durable Communication: Consistently Connecting DuraMAT Messages with Target Audiences

This webinar addresses communications strategies for the Durable Module Materials Consortium (DuraMAT). DuraMAT focuses on precompetitive research needs in solar photovoltaic (PV) module packaging to accelerate a sustainable, just, and equitable transition to zero carbon electricity generation by 2035. In the webinar, an interactive exercise helps researchers write better article titles. DuraMAT communications goals and lessons learned are discussed. Key audiences for DuraMAT communication products are identified. Next steps for DuraMAT communications are summarized.

audiences↗

DOE OSTI2019

Communicating Technical Information: Different Approaches for Different Audiences - 19399

The Canadian Nuclear Safety Commission (CNSC), Canada's independent nuclear regulator, has a 70- year history of regulating nuclear safety in Canada. Part of the CNSC's mandate is to disseminate objective scientific, technical and regulatory information to the public. The CNSC prides itself on being transparent with the public, and openly sharing scientific, technical and regulatory information on its regulatory activities with stakeholders. We value the public's feedback, and have a robust public participation program to allow for public involvement in the CNSC's activities. However, different audiences have different needs based on their level of technical knowledge and expertise. The CNSC's experience with stakeholder interactions has demonstrated the need to balance the dissemination of technical information through different communication platforms, in order to satisfy the needs of various intended audiences. This paper will focus on the radioactive waste management communications methods that the CNSC has implemented for two distinct audiences: 1. Audiences with little or no technical background: Communications with this audience requires techniques to make highly technical concepts more understandable. The focus is on educating about matters related to radioactive waste management, and informing about the safety aspects behind the regulation of radioactive waste. 2. Audiences with previous knowledge and experience with nuclear matters: Communications with this audience requires techniques to ensure that as much technical information and data as possible is available to inform stakeholders. The focus is on giving access to studies, research and raw data, in order to allow this audience to inform themselves, and potentially bring new perspectives to the CNSC's attention that could be used in regulatory oversight activities. In its capacity to disseminate scientific and technical information to the public as required by legislation, the CNSC holds a unique position compared with other Canadian regulatory bodies. The CNSC is one of the only Canadian regulators which: - Has a public hearing process which enables the public and Indigenous groups to express their issues and concerns directly to the decision-maker (the Commission) - Publishes regular regulatory oversight reports (report card on industry) that assess the safety performance of all its licensees - Publishes responses to all public comments received during consultation periods in our environmental assessment processes as well as our regulatory framework processes, including draft regulatory documents, discussions papers and proposed regulations - Has an independent environmental monitoring program, allowing the public access to environmental data. The program also seeks public and Indigenous input with respect to proposed environmental sampling campaigns, including suggestions on the samples to be taken and sampling locations. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2019

Nuclear Crisis Communication in an Era of Fake News and Media Overload - 19414

Over the past several decades, the nuclear industry has worked diligently to improve the security and safety aspects of their technology, but it has failed to meet the challenge of the public's negative perception. Studies have shown that nuclear energy and nuclear waste evoke fear among the general populace because people see risks as immediate, unknown, uncontrollable, and potentially catastrophic. To some extent, negative public perception challenges for the nuclear industry are primarily a consequence of its own inability to communicate the benefits of nuclear science effectively with the lay public. While effective and trustworthy communication cannot guarantee success, it helps shape public opinion, and for a routinely misperceived project like a nuclear facility, that is paramount. Fukushima was the first nuclear accident to occur in the world where citizens have access to 24/7 news channels and the ability to respond in a real-time manner through social media outlets. Following the Fukushima accident, social media sites were filled with information regarding nuclear energy that were based more on mass rumor and even paranoia than facts. More locally, we have seen this trend following what was a minor external radiation release event at the WIPP in February 14, 2014. Many online news sources were flooded with anti-nuke stories aimed at pushing a fear of radiation, such as inferring an increase in cancer rates among the public from this minor incident; which was exactly the opposite of what was true. Today, when the public gets its news from social media and online sources, people are faced with rapidly changing and contrasting interpretations of the same story, depending on when they accessed the latest news. They are also increasingly vulnerable to fake news, including disinformation deliberately planted and cultivated by the anti-nuclear movement. Public reactions following these nuclear events reinforced the value of effective communication in maintaining the high level of transparency necessary for long-term, local acceptance and support for nuclear facilities. A lack of trustworthy communication leaves a vacuum that can be quickly filled by rumors and fake information. When dealing with a nuclear crisis, failure to recognize the rapidly changing and contrasting media framing, or believing fake news could have very real and catastrophic consequences. Trusted organizations must swiftly take charge and guide the way in which the crisis is framed to keep the public adequately and accurately informed. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2017

Risk assessment of safety-critical data communication in digital safety feature control system - 205

As one of the safety-critical systems in Advanced Power Reactor-1400 (APR-1400) nuclear power plant (NPP), the Engineered Safety Feature-Component Control System (ESF-CCS) employs safety data link and network communication for transmitting safety component actuation to effectively facilitate various safety-critical field controllers. However, data communication failure risk in the ESF-CCS has yet to be fully quantified, the probability that a safety-critical system in digitalized NPP becomes unsafe due to a network failure must be evaluated to quantify the risk of digital I and C system. In this study, a fault tree model was developed to assess the data link and data network failure-induced unavailability of a safety-critical system function used to generate an automated control signal for actuating design basis accident mitigation equipment. Especially, the risk of data communication failure in a digital safety feature control system was analyzed in consideration of interconnection between safety-critical controllers and the fault-tolerant algorithm implemented in the network configuration. Based on the developed fault tree model, case studies were performed to quantitatively assess the unavailability of ESF-CCS signal generation due to safety data link and network failure and their risk effect on safety signal generation unavailability. This study is expected to provide risk information on the safety-critical data communication in a digitalized NPP instrumentation and control system. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗