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At least 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Field-Programmable Gate Array Implementation of a Single Photon-Counting Receive Modem

We present a field-programmable gate array (FPGA) implementation of a single photon-counting receive modem for a pulse position modulated signal. The modem is compliant with the Consultative Committee for Space Data Systems (CCSDS) High Photon Efficiency (HPE) Optical Communications Coding and Synchronization standard and is capable of a maximum data rate of 267 Mbps. The system is designed on a commercial off-the-shelf FPGA platform and utilizes superconducting nanowire single photon counting detectors, analog to digital converters (ADC s) to sample the detectors, and two FPGAs. Symbol timing recovery, photon counting, convolutional deinterleaving, and codeword synchronization areis performed in the first FPGA. The second FPGA performs iterative decoding on each codeword of the serially concatenated pulse position modulated (SCPPM) signal. A digital filter is included to compensate for timing jitter of the detector, and the decoder throughput can be modified adjusted through reconfigurable parallelization. The decoder also implements a resource-efficient, algorithmic polynomial interleaver and deinterleaver. Both FPGAs can be reconfigured to switch between pulse position modulation (PPM)-16 and PPM-32 with code rates 1/3, 1/2, and 2/3. In this paper, we describe the receiver architecture and FPGA implementation of the timing recovery loop and SCPPM decoder, FPGA utilization for the different modes, and receive modem characterization test results.

Field-programmable Gate Array↗
NASA NTRS2023

JPSS-3 VIIRS Version 2 at-Launch Relative Spectral Response Characterization

The JPSS-3 VIIRS sensor has completed its pre-launch test program including measurements for characterizing the VIIRS relative spectral response (RSR) in support of the Sensor and Environmental Data Records (SDR and EDR, resp.) that will be generated from VIIRS on-orbit observations. Government team subject matter experts of the VIIRS DAWG have analyzed the VIIRS spectral measurements and produced the VIIRS spectral characterization, in the form of band-average and supporting detector level RSR for each VIIRS band. The characterization is based upon the analysis of independent SpMA dual monochromator (all bands) and GSFC GLAMR laser system (reflectance bands only) spectral measurements. The SpMA and GLAMR measurements for reflectance bands (DNB LGS and MGS, I1-I3, M1-M11) were combined to produce a “fused” RSR. For emissive bands (I4, I5, M12-M16), the SpMA measurements provide the characterization. The effort has led to the VIIRS Version 2 RSR release, the official at-launch RSR characterization for the JPSS-3 VIIRS mission. The JPSS-3 RSR are a close match to those of JPSS-2. An assessment on compliance with spectral performance metrics finds that VIIRS band-average RSR are compliant on nearly all metrics, with only a single minor exception. The Version 2 RSR release is available under EAR99 restrictions to the science community on the restricted access NASA Sharepoint.

Chris Moeller↗
NASA NTRSDate not supplied

Extending CF Conventions to Enhance Data FAIRness for Atmospheric Composition Observations

The Hierarchical Data Format (HDF) and Network Common Data Form (NetCDF) are data file formats created to aid users in the creation or use of scientific data. These file formats are useful for handling large data volumes and hosting extensive metadata as global, group, or variable attributes and are popular with the modeling community. HDF and NetCDF files are widely used with atmospheric remote sensing data and have been used to support measurements from numerous field campaigns, from satellite to aircraft or ground and mobile based measurements. The files from airborne field studies, however, vary greatly in terms of the file structure and the amount and content of their metadata. Information relevant to the file that can be useful to the user such as the data producer, location where data was taken, variable descriptions, or information about the instrument might not be included in the file. Recently, the Measurements of Aerosols, Clouds, and their Interactions for Earth System Models (MACIE) group started a grassroots effort to develop a CF-based template for the HDF and NetCDF files for field studies, with the aim of making the data products more interoperable and usable. This template seeks to make the files more compliant to Climate and Forecast (CF) metadata conventions and to standardize the file structure and the global and variable attributes. The template would help to ensure that HDF and NetCDF files contain adequate metadata to better support their use for research, e.g., the modeling community, and to enhance the usability and interoperability of data for research communities at large. The draft template has been applied to recent field studies for various instruments and their merge files in support of the Atmosphere Observing System (AOS) project. The details of the revised template are to be presented, as well as examples of the implementation of these requirements for merge files and lidar observation data files and issues revealed during the implementation process.

Sean Leavor↗
NASA NTRSDate not supplied

The State of CryptoLib – The Open-Source Satellite Cryptography Library

What state would the world be in if all internet traffic was unencrypted? Imagine an alternate universe where you can plug a packet sniffing device into your home internet and capture the web traffic of the entire world. It seems obvious that this scenario is less than desirable. If we would not allow this for the internet, why would we allow this in the space domain? With the advent of open-source ground stations, commercial off the shelf hardware, and ground stations as a service, the barrier to entry for space communications is rapidly lowering. New players enter the space realm everydayevery day, and the presence of tools to allow apprentice evildoers the ability to exploit satellite communications is on the horizon. Not only are legacy missions at risk, but future missions are as well - particularly lower budget science missions with more stringent sciencesize, weight, and power constraints. that may find it difficult to utilize hardware-based encryption solutions. In terms of Civilian Aerospace, NASA Standard 1006 generally directs that missions "shall protect the command stack with encryption that meets or exceeds Federal Information Processing Standards (FIPS) 140". Fortunately, the Consultative Committee for Space Data Systems (CCSDS) has published an international standard on Space Data Link Security. The combination of these two forces has resulted in CryptoLib - an open-source, C-based, encryption library that aims to be CCSDS SDLS compliant. CryptoLib is designed to support smaller missions on a tight budget that may be subject to the more stringent command link encryption requirements. Additionally, CryptoLib serves as an underpinning in JPL's Key Management & Cryptography (KMC) suite and is also designed to function as a 'drop-in' for smaller missions. CryptoLib is in active development and currently provides Telecommand (TC), Telemetry (TM), and Advanced Orbiting Systems (AOS) encryption and decryption capabilities with a variety of encryption and authentication schemes. This presentation will report the latest features, current status, and future plans for CryptoLib.

open-source encryption↗
NASA NTRS2024

Shape Memory Alloy Material Maturation (SMA)

The Shape Memory Alloy (SMA) project will evaluate, process, and refine 3 SMA materials that have the potential to provide the properties needed to enable various technologies for human exploration missions on the Moon and Mars. The work will focus on the development and identification of a new SMA alloy targeted at enabling compliant rover tires capable of the extreme demands (high loads, faster drive speeds, extreme cold temperatures and exceedingly long mission durations). The necessary work will include the development of key material testing capabilities that will enable material properties development from 40K – 400K for all properties needed to qualify space flight hardware (Tensile, Fatigue/Durability, etc.). The SMA wire properties will be input into a database and model, ultimately to disseminate material property design data (for 1 alloy only) as parameters for finite element modeling of a tire structure.

Andrea Marchica↗
NASA NTRS2024

Acquisition of and Access to Research Omics Data

Omics data are essential for understanding the myriad and complex effects of space environments on humans. To assure maximum benefit from these kinds of data, the NASA Human Research Program Data Management Plan stipulates that human omics data should be archived within and accessed through the NASA Life Sciences Portal (NLSP). The NLSP has the capability to acquire and provision access to omics (and other kinds of) research results for individual and ad-hoc groups of subjects at the direction of institutional review boards, or other authorizing bodies or individuals, per institutional, program and investigation-specific policies and procedures. However, because some single-subject omics data, like CT scans and other kinds of large, complex biomedical data, could be used to identify heretofore unknown risks to the subject’s health, or, in certain cases, be used to identify a subject, NASA Policy Directive 7170.1 describes various policies regarding the management of and access to “research genetic testing” data, which includes many kinds of omics data. For example, NPD 7170.1 prohibits access to human research genetic data by NASA personnel who make employment decisions for the subjects from whom the data were obtained. To meet the objective of acquiring research omics data for NLSP in compliance with the policies in NPD 7170.1 and other applicable NASA policies, we designed NOMADS (the NLSP Omics Multimodal Acquisition of Data System), a new component that supports the transfer of large research data files, including research genetic testing data, using one of several different transfer mechanisms. The choice of mechanism is made by the submitter of the data, with guiding information from the system, and is likely to often be determined in large part by the nature and source location of the data. For example, for small files where the source data files are not already stored in a cloud storage system, users are likely to prefer to transfer their data to the NLSP via a web browser. Conversely, for large sets of files already organized and stored in a cloud storage system, users may opt for NOMAD’s cloud-to-cloud transfer method. All omics datasets targeted for the NASA Life Sciences Data Archive must pass a variety of quality checks to ensure data integrity and adherence to the standards defined by the LSDA Data Submission Guidelines (DSG) (see https://nlsp.nasa.gov/explore/lsdahome/datasubmit). These include requirements that data are consistent with open standards established by the omics community. Non-compliant data will not be accepted however archivists are available to advise submitters on how to revise data submissions and re-submit until compliance is achieved. Following compliance with the LSDA DSG, omics data next undergo a variety of additional quality checks to ensure the data meet omics community standards. Domain specific Omics data quality control tools and techniques are continually evolving and linked to the advancements in omics assays utilized and thus, the tools and techniques utilized by the LSDA for data quality control and validation will need to be sustained accordingly. All human omics data will be access controlled according to the policies described above, and requiring IRB approval for any additional access grants once the data are acquired (including access for analysis using the NLSP workspace tools).

Omics↗
NASA NTRS2024

Demonstration of GaN HEMT MMIC High-Power Amplifier for Lunar Proximity Communications

In this paper, we demonstrate a high efficiency, Ka-band (23.15 to 23.55 GHz) GaN HEMT MMIC based single-ended high power amplifier (HPA). The measured Pout, Gain, PAE, RMS EVM for Offset-QPSK, 8PSK, 16APSK, and 32APSK waveforms, 3rd-order IMD products, noise figure, and phase noise are presented. The results indicate that the saturated output power (P sat ) and the small signal Gain are on the order of 38.8 dBm (7.6 W) and 29.3 dB, respectively. The PAE at Psat is 20.0%. At the 1-dB compression point, the RMS EVM and the out-of-band spectral regrowth are less than 6% and –26 dBc respectively, for all four waveforms. Additionally, the spectrum is in compliance with the NTIA mask requirements for all four waveforms. The output 3rd-order intercept point (OIP3) is on the order of 42 dBm. The noise figure is less than 9.5 dB. The SSB phase noise spectral density is compliant with the envelope defined by the MIL-STD-188-164C. The HPA can enable proximity forward links between the orbiting Gateway/relay satellites and the lunar surface elements and cross links between relay satellites.

Ka-band↗
NASA NTRS2021

Collective Transport of Unconstrained Objects via Implicit Coordination and Adaptive Compliance

We present a decentralized control algorithm for robots to aid in carrying an unknown load. Coordination occurs solely through sensing of the forces on or movement of the shared load. Robots prevent undesired motion of the load while permitting movement in the task-relevant subspace, and stabilize against unexpected events by a transient decrease in compliance. The algorithm requires no direct communication between agents, and minimal knowledge of the system or task. We demonstrate the approach in simulation using a commercially available compliant robotic platform.

Nicole E. Carey↗
NASA NTRSDate not supplied

The Nasa SRA Process as It Relates to Open-Source Workflows Developed for GeneLab Data Processing

To release open, standards-compliant processed data sets in the Open Science Data Repository (OSDR), the GeneLab Data Processing team works with the scientific community through the OSDR Analysis Working Groups to design and build open-source data processing pipelines. Once baselined internally, these pipelines are wrapped into workflows and published on the NASA GeneLab Data Processing public GitHub repository along with detailed instructions for installation and use. Each workflow must be approved through NASA's Software Release Authorization (SRA) process prior to publishing. However, the SRA process lacks sufficient documentation and clarity regarding which forms are applicable for new open-source software that utilizes publicly available 3rd party tools, and the SRA process can take several months to complete, making sharing software outside of NASA cumbersome and in contradiction with the concept of Open Science. Furthermore, the SRA process was designed as a one-size fits all approach and thus many of the questions asked are not applicable to our open-source workflows. Here we describe the software provided on the NASA GeneLab Data Processing GitHub repository, summarize our experiences with the SRA process to release these software, and propose a more stream-lined approach for review of open-source projects.

Software Release Authorization↗
NASA NTRSDate not supplied

A Photon Counting Ground Receiver for Free-Space Optical Communications

The National Aeronautics and Space Administration is developing a photon counting ground receiver for free-space optical communications. The receiver consists of a fiber interconnect, superconducting nanowire single photon counting detectors (SNSPDs), and a field programmable gate array (FPGA) based receive modem. This receiver is compliant with the Consultative Committee for Space Data Systems (CCSDS) Optical Communications High Photon Efficiency standard, which is used in the low photon flux communications regime, including on the upcoming Optical Artemis-2 Orion communications demonstration. The receiver architecture is modular, can be scaled for data rate, and is designed with primarily commercial-off-the-shelf technology. Two fiber interconnect and detector architectures are being prototyped. The first uses a few-mode-fiber coupled to a 16-channel SNSPD array and the second architecture uses a photonic lantern coupled to 7 single-pixel SNSPDs. Photon counting, symbol timing recovery, demodulation and decoding is done using several FPGA cards. This presentation describes the unique features of the ground receiver, performance test results, and challenges with using commercial SNSPDs in free-space optical communications.

Jennifer N Downey↗
NASA NTRSDate not supplied

Artemis III Sleep Scheduling with HYPNOS Mission Planning Tool HLS Yawn Prevention N Outer Space (HYPNOS)

HYPNOS ingests critical event data, such as burns and docking, and automatically shifts the crew’s sleep schedule to support these events where possible, while still being compliant with medical restrictions. HYPNOS analyzes the crew’s timeline in 3 states: 1) Awake, meaning the crew is active for work hours 2) Pre- and Post-Sleep, awake periods of limited activity as the crew gets ready to sleep or is waking up 3) Sleep, where the crew is inactive as they rest

Levi Gosdin↗
NASA NTRSDate not supplied

The NASA SRA Process as it Relates to Open-Source Workflows Developed for GeneLab Data Processing

To release open, standards-compliant processed data sets in the Open Science Data Repository (OSDR), the GeneLab Data Processing team works with the scientific community through the OSDR Analysis Working Groups to design and build open-source data processing pipelines. Once baselined internally, these pipelines are wrapped into workflows and published on the NASA GeneLab Data Processing public GitHub repository along with detailed instructions for installation and use. Each workflow must be approved through NASA's Software Release Authorization (SRA) process prior to publishing. However, the SRA process lacks sufficient documentation and clarity regarding which forms are applicable for new open-source software that utilizes publicly available 3rd party tools, and the SRA process can take several months to complete, making sharing software outside of NASA cumbersome and in contradiction with the concept of Open Science. Furthermore, the SRA process was designed as a one-size fits all approach and thus many of the questions asked are not applicable to our open-source workflows. Here we describe the software provided on the NASA GeneLab Data Processing GitHub repository, summarize our experiences with the SRA process to release these software, and propose a more stream-lined approach for review of open-source projects.

Software Release Authorization↗
NASA NTRSDate not supplied

Enabling Universal Access to Power on the Lunar Surface

The National Aeronautics and Space Administration (NASA) Artemis Missions will return human astronauts to the lunar surface, demonstrate technologies that establish a sustained presence on the lunar surface and enable human missions to Mars, and help create a lunar commercial economy. Creating a sustained permanent presence on the lunar surface will require access to continuous and highly reliable power to support mission needs. During Artemis, lunar surface operations will evolve and grow over time (years), requiring an increase in the amount of power needed (100s of kW) and distance that the power must be transmitted (up to 10 km during early Artemis missions). A lunar commercial economy is likely to exceed this power demand to the MW level and distance in the 100s of km. This increased distance and demand for highly reliable power drives the need to create an electric power grid by connecting localized lunar power systems (e.g., habitats, in-situ resource utilization plants, etc.), each containing one or more loads and/or sources. Developing a lunar surface power grid will allow lunar surface operations to resemble electrical utility operations on Earth; it allows power to be generated where it is convenient and allows power to be consumed where it is convenient and required. A lunar surface electric power grid will facilitate the growth of a lunar commercial economy because it provides a means to connect new loads to an existing electrical power system. A common standardized interface to the grid and a set of standardized voltages is required to take full advantage of the benefits of an electric power grid, similar to the terrestrial power grid. NASA Glenn Research Center is leading an effort to create universal access to power through the development of the Universal Modular Interface Converter (UMIC). The UMIC is designed to have a common interface that connects sources and loads compliant with the International Space Power System Interoperability Standard (ISPSIS) to a higher voltage AC transmission system or power grid. This presentation will further discuss the evolution of power during the Artemis missions, challenges associated with creating a sustained presence on the lunar surface, progress made on the UMIC, and future opportunities for technology development and standards.

space power systems↗
NASA NTRSDate not supplied

Service Provider Agnostic Adaptive Coding and Modulation System Design

Commercial service providers (CSPs) are increasingly used to provide communications services to near-Earth science and exploration missions. CSPs commonly utilize modems that are designed to implement adaptive coding and modulation (ACM) in unique ways with modems from the same vendor. However, some missions cannot fly a matching vendor modem, either because the vendor only designs modems for terrestrial use, or the mission needs to fly a software defined radio. We present an ACM system design that allows missions to implement ACM on DVB-S2 compliant CSP links without needing to fly a modem from the same vendor the CSP uses. We implement and test our design in an emulated communications testbed. These tests demonstrate that our ACM system design can successfully adapt to link quality changes up to 6.12 dB/second.

Adaptive coding and modulation↗
NASA NTRSDate not supplied

Service Provider Agnostic Adaptive Coding and Modulation System Design

Commercial service providers (CSPs) are increasingly used to provide communications services to near-Earth science and exploration missions. CSPs commonly utilize modems that are designed to implement adaptive coding and modulation (ACM) in unique ways with modems from the same vendor. However, some missions cannot fly a matching vendor modem, either because the vendor only designs modems for terrestrial use, or the mission needs to fly a software defined radio. We present an ACM system design that allows missions to implement ACM on DVB-S2 compliant CSP links without needing to fly a modem from the same vendor the CSP uses. We implement and test our design in an emulated communications testbed. These tests demonstrate that our ACM system design can successfully adapt to link quality changes up to 6.12 dB/second.

Adaptive coding and modulation↗
NASA NTRS2024

Real-Time Optical Receiver Decoder Architecture Changes for High-Speed Modes

The National Aeronautics and Space Administration (NASA) at Glenn Research Center (GRC) has developed an optical communications transmitter and receiver using Commercial-off-the-shelf (COTS) components. The goal of this project is to become fully compliant with Consultative Committee for Space Data Systems (CCSDS) High Photon Efficiency (HPE) Optical Communications Coding and Synchronization standard. The receive modem’s decoder has been modified using shift registers to enable the decoding of higher data rate pulse-position modulation (PPM) 4 and PPM-8 signals. PPM-4 and PPM-8 is then verified by comparing the codeword error rate (CWER) of a hardware implementation to a software simulation. The changes show the capability to decode PPM-4 and PPM-8 for a single decoder. This memorandum details the changes made, the performance achieved with the changes, and necessary future work.

PPM↗
NASA NTRS2024

Applying Generative-AI to NASA Documentation and Processes

This research and development project leverages generative-AI to assist in the generation of software process documentation based on NASA standards. By utilizing fine-tuned AI models, the proposed system will analyze NASA's software guidelines, helping to translate them into well-structured, compliant process documents. This assistance can reduce the manual effort required to produce such documentation, enhance consistency, and assure alignment with NASA's stringent software development and operational requirements. In addition to assisting in the generation of software process documentation, the project explores how generative-AI can help create audit checklists as well as assess the compliance of NASA provider documentation against applicable NASA standards. This approach would support the compliance auditing process, providing real-time insights and assessments. The intended result will be a streamlined process, potentially including a Python-based tool and database, that improves audit efficiency, reduces human error, lowers manpower costs and required manhours, and assures continuous compliance with NASA and industry evolving standards for safety-critical software development. Future task might be to investigate the software industry approach and standards for potential collaboration.

NASA Standards↗
NASA NTRSDate not supplied

Separation Assurance in Urban Air Mobility Systems Using Shared Scheduling Protocols

Ensuring safe separation between aircraft is a critical challenge in air traffic management, particularly in urban air mobility (UAM) environments where high traffic density and low altitudes require precise control. In these environments, conflicts often arise at the intersections of flight corridors, posing significant risks. We propose a tactical separation approach leveraging shared scheduling protocols, originally designed for Ethernet networks and operating systems, to coordinate access to these intersections. Using a decentralized Markov decision process framework, the proposed approach enables aircraft to autonomously adjust their speed and timing as they navigate these critical areas, maintaining safe separation without a central controller. We evaluate the effectiveness of this approach in simulated UAM scenarios, demonstrating its ability to reduce separation violations to zero while acknowledging trade-offs in flight times as traffic density increases. Additionally, we explore the impact of non-compliant aircraft, showing that while shared scheduling protocols can no longer guarantee safe separation, they still provide significant improvements over systems without scheduling protocols.

Separation Assurance↗