Program Specification Plan for the Determination of Atmospheric Effects on Laser Space Communications, Volume II
Program specifications for laser space communication study
PROGRAM MANAGEMENT↗
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L-Band System Engineering - Concepts of Use, Systems Performance Requirements, and Architecture
This document is being provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-band and L-band Communications Standard Development. Task 7 was motivated by the five year technology assessment performed for the Federal Aviation Administration (FAA) under the joint FAA-EUROCONTROL cooperative research Action Plan (AP-17), also known as the Future Communications Study (FCS). It was based on direction provided by the FAA project-level agreement (PLA FY09_G1M.02-02v1) for "New ATM Requirements-Future Communications." Task 7 was separated into two distinct subtasks, each aligned with specific work elements and deliverable items. Subtask 7-1 addressed C-band airport surface data communications standards development, systems engineering, test bed development, and tests/demonstrations to establish operational capability for what is now referred to as the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2, which is the subject of this report, focused on preliminary systems engineering and support of joint FAA/EUROCONTROL development and evaluation of a future L-band (960 to 1164 MHz) air/ground (A/G) communication system known as the L-band digital aeronautical communications system (L-DACS), which was defined during the FCS. The proposed L-DACS will be capable of providing ATM services in continental airspace in the 2020+ timeframe. Subtask 7-2 was performed in two phases. Phase I featured development of Concepts of Use, high level functional analyses, performance of initial L-band system safety and security risk assessments, and development of high level requirements and architectures. It also included the aforementioned support of joint L-DACS development and evaluation, including inputs to L-DACS design specifications. Phase II provided a refinement of the systems engineering activities performed during Phase I, along with continued joint FAA/EUROCONTROL L-DACS development and evaluation support.
Henriksen, Stephen↗
Man-Machine Interaction Design and Analysis System (MIDAS): Memory Representation and Procedural Implications for Airborne Communication Modalities
The Man-Machine Interaction Design and Analysis System (MIDAS) has been under development for the past ten years through a joint US Army and NASA cooperative agreement. MIDAS represents multiple human operators and selected perceptual, cognitive, and physical functions of those operators as they interact with simulated systems. MIDAS has been used as an integrated predictive framework for the investigation of human/machine systems, particularly in situations with high demands on the operators. Specific examples include: nuclear power plant crew simulation, military helicopter flight crew response, and police force emergency dispatch. In recent applications to airborne systems development, MIDAS has demonstrated an ability to predict flight crew decision-making and procedural behavior when interacting with automated flight management systems and Air Traffic Control. In this paper we describe two enhancements to MIDAS. The first involves the addition of working memory in the form of an articulatory buffer for verbal communication protocols and a visuo-spatial buffer for communications via digital datalink. The second enhancement is a representation of multiple operators working as a team. This enhanced model was used to predict the performance of human flight crews and their level of compliance with commercial aviation communication procedures. We show how the data produced by MIDAS compares with flight crew performance data from full mission simulations. Finally, we discuss the use of these features to study communications issues connected with aircraft-based separation assurance.
Corker, Kevin M.↗
Computational Models of Human Performance: Validation of Memory and Procedural Representation in Advanced Air/Ground Simulation
The Man-Machine Interaction Design and Analysis System (MIDAS) under joint U.S. Army and NASA cooperative is intended to assist designers of complex human/automation systems in successfully incorporating human performance capabilities and limitations into decision and action support systems. MIDAS is a computational representation of multiple human operators, selected perceptual, cognitive, and physical functions of those operators, and the physical/functional representation of the equipment with which they operate. MIDAS has been used as an integrated predictive framework for the investigation of human/machine systems, particularly in situations with high demands on the operators. We have extended the human performance models to include representation of both human operators and intelligent aiding systems in flight management, and air traffic service. The focus of this development is to predict human performance in response to aiding system developed to identify aircraft conflict and to assist in the shared authority for resolution. The demands of this application requires representation of many intelligent agents sharing world-models, coordinating action/intention, and cooperative scheduling of goals and action in an somewhat unpredictable world of operations. In recent applications to airborne systems development, MIDAS has demonstrated an ability to predict flight crew decision-making and procedural behavior when interacting with automated flight management systems and Air Traffic Control. In this paper, we describe two enhancements to MIDAS. The first involves the addition of working memory in the form of an articulatory buffer for verbal communication protocols and a visuo-spatial buffer for communications via digital datalink. The second enhancement is a representation of multiple operators working as a team. This enhanced model was used to predict the performance of human flight crews and their level of compliance with commercial aviation communication procedures. We show how the data produced by MIDAS compares with flight crew performance data from full mission simulations. Finally, we discuss the use of these features to study communication issues connected with aircraft-based separation assurance.
Corker, Kevin M.↗
One third of the world - A review of Pacific islands telecommunications requirements
This paper describes the Pacific Basin Communications Study, an assessment of Pacific islands telecommunications requirements, recently completed by the Public Service Satellite Consortium under contract with the National Aeronautics and Space Administration (NASA). The study describes extant and planned telecommunications systems in the region, examines user needs in terms of the development of governmental, social and commercial activities, and proposes and describes alternative technological solutions to communications problems. Questions of financing, implementation, management, costs and benefits of a regional telecommunications system are discussed. This paper describes user requirements based on six months of field investigation and technological options for improving telecommunications in the Pacific islands.
Hurd, J. N.↗
Identification of Technologies for Provision of Future Aeronautical Communications
This report describes the process, findings, and recommendations of the second of three phases of the Future Communications Study (FCS) technology investigation conducted by NASA Glenn Research Center and ITT Advanced Engineering & Sciences Division for the Federal Aviation Administration (FAA). The FCS is a collaborative research effort between the FAA and Eurocontrol to address frequency congestion and spectrum depletion for safety critical airground communications. The goal of the technology investigation is to identify technologies that can support the longterm aeronautical mobile communication operating concept. A derived set of evaluation criteria traceable to the operating concept document is presented. An adaptation of the analytical hierarchy process is described and recommended for selecting candidates for detailed evaluation. Evaluations of a subset of technologies brought forward from the prescreening process are provided. Five of those are identified as candidates with the highest potential for continental airspace solutions in L-band (P-34, W-CDMA, LDL, B-VHF, and E-TDMA). Additional technologies are identified as best performers in the unique environments of remote/oceanic airspace in the satellite bands (Inmarsat SBB and a custom satellite solution) and the airport flight domain in C-band (802.16e). Details of the evaluation criteria, channel models, and the technology evaluations are provided in appendixes.
Gilbert, Tricia↗
Enabling Dynamic Vehicle Analyses With Improved Atmospheric Attenuation Models in Glenn Research Center Communication Analysis Suite
To aid in meeting the NASA objective of returning humans to the Moon, the Glenn Research Center’s Communication Analysis Suite was augmented with two distinct capabilities. The first capability added was the vehicle propagator. This allows the addition of dynamic aircraft and ground vehicles around any celestial body within the solar system during an analysis. This functionality interpolates the position and velocity of the vehicle relative to a celestial body at the time steps analyzed using the type of path and either a series of waypoints or a direction and duration of travel. The implications of this new capability include lunar rovers and/or drones, such as Dragonfly, where the vehicle propagator will analyze the communications architecture. The newly created vehicle propagator is now in use in communications studies for the 2024 lunar missions, simulating the movement of lunar rovers across the Moon’s southern pole. The second capability added was the augmentation of the atmospheric attenuation model. The previous model did not have a uniform low-elevation attenuation model due to the trigonometric approximation for path length and the exponential nature of low-elevation scintillation. User-defined weather parameters were also added to the updated atmospheric attenuation model. The previous model solely used tabular data based upon the season and location of the transmitting antenna. Multiple simulations of the same configuration now return different results based on the differing weather parameters. Cognitive communications analysis efforts can use this second capability to generate neural network training data based on differing weather conditions at utilized ground stations, a critical step in allowing neural networks to learn how weather parameters impact communications performance.
vehicle propagation↗
Toward a NASA Deep Space Optical Communications System
As discussed at SpaceOps in 2016, we expect the data rates from deep space missions to increase approximately one order of magnitude per decade for the next 50 years. The first order of magnitude improvement will come from existing plans for radio frequency (RF) communications including enhancements to both spacecraft and Deep Space Network (DSN) facilities. The next two orders of magnitude are predicted to come from the introduction of deep space optical communications. Studies indicate that optical receive apertures of between 8m12m are desired. The large cost of dedicated receive telescopes makes this method unrealistic – at least in the near-term. The cost of large optical ground terminals is driven primarily by the cost of the optics and by the cost of a stable structure for the telescope. We propose a novel hybrid design in which existing DSN 34m beam waveguide (BWG) radio antennas can be modified to include an 8m equivalent optical primary. By utilizing a low-cost segmented spherical mirror optical design, pioneered by the optical astronomical community, and by exploiting the already existing extremely stable large radio aperture structures in the DSN, we can minimize both of these cost drivers for implementing large optical communications ground terminals. Two collocated hybrid RF/optical antennas could be arrayed to synthesize the performance of an 11.3m receive aperture to support more capable or more distant space missions or used separately to communicate with two optical spacecraft simultaneously. NASA is in the midst of building six new 34m BWG antennas in the DSN. The final two are planned to be built at the DSN Goldstone, California and Canberra complexes. We are now investigating building these last two antennas as RF/optical hybrids. By delaying their operational dates by two years, we would be able to add the 8m optical receive capability for these two antennas while fitting within existing budgetary constraints. This paper describes the hybrid antenna design, the technical challenges being addressed, and plan for using this concept, together with ongoing work on optical flight terminals, to infuse operation optical communications into deep space missions.
Cornwell, Donald M.↗
Exa-Graph/neve
Microbenchmark to study communication and memory-access performance of graphs.
Ghosh, Sayan↗
Characterization of Plasma Protein Alterations in Pregnant and Postpartum Individuals Living With HIV to Support Physiologically-Based Pharmacokinetic Model Development
Alterations in plasma protein concentrations in pregnant and postpartum individuals can influence antiretroviral (ARV) pharmacokinetics. Physiologically-based pharmacokinetic (PBPK) models can serve to inform drug dosing decisions in understudied populations. However, development of such models requires quantitative physiological information (e.g., changes in plasma protein concentration) from the population of interest. Objective: To quantitatively describe the time-course of albumin and α1-acid glycoprotein (AAG) concentrations in pregnant and postpartum women living with HIV. Serum and plasma protein concentrations procured from the International Maternal Pediatric Adolescent AIDS Clinical Trial Protocol 1026s (P1026s) were analyzed using a generalized additive modeling approach. Separate non-parametric smoothing splines were fit to albumin and AAG concentrations as functions of gestational age or postpartum duration. The analysis included 871 and 757 serum albumin concentrations collected from 380 pregnant (~20 to 42 wks gestation) and 354 postpartum (0 to 46 wks postpartum) women, respectively. Thirty-six and 32 plasma AAG concentrations from 31 pregnant (~24 to 38 wks gestation) and 30 postpartum women (~2–13 wks postpartum), respectively, were available for analysis. Estimated mean albumin concentrations remained stable from 20 wks gestation to term (33.4 to 34.3 g/L); whereas, concentrations rapidly increased postpartum until stabilizing at ~42.3 g/L 15 wk after delivery. Estimated AAG concentrations slightly decreased from 24 wks gestation to term (53.6 and 44.9 mg/dL) while postpartum levels were elevated at two wks after delivery (126.1 mg/dL) and subsequently declined thereafter. Computational functions were developed to quantitatively communicate study results in a form that can be readily utilized for PBPK model development. By characterizing the trajectory of plasma protein concentrations in pregnant and postpartum women living with HIV, our analysis can increase confidence in PBPK model predictions for HIV antiretrovirals and better inform drug dosing decisions in this understudied population.
60 APPLIED LIFE SCIENCES↗
Participation of the holmdel station in the telstar project
The facility for satellite communication studies at Holmdel, New Jersey, was originally established to take part in Project Echo. This paper describes the modifications required to participate in the Telstar experiments and the results obtained during operations from July 10 to November 9, 1962. Reception of television from the satellite was successfully accomplished, studies were made of the signal levels, and the changes with time of the satellite spin rate and spin axis orientation were determined.
TELSTAR SATELLITE↗
NASA 60 GHz intersatellite communication link definition study. Addendum A: Mixed baseband and IF signals
As part of a definition study for a 60 GHz intersatellite communications link system (ICLS), baseline design concepts for a channelized crosslink were identified. The crosslink would allow communications between geostationary satellites of the planned Tracking and Data Acquisition System (TDAS) and would accommodate a mixture of frequency translation coherent links (bent pipe links) and baseband-in/baseband-out links (mod/demod links). A 60 GHz communication system was developed for sizing and analyzing the crosslink. For the coherent links this system translates incoming signals directly up to the 60 GHz band; trunks the signals across from one satellite to a second satellite at 60 GHz then down converts to the proper frequency for re-transmission from the second satellite without converting to any intermediate frequencies. For the baseband-in/baseband-out links the baseband data is modulated on to the 60 GHz carrier at the transmitting satellite and demodulated at the receiving satellite. The frequency plan, equipment diagrams, and link calculations are presented along with results from sizing and reliability analyses.
Source record↗
The Telecommunications and Data Acquisition Report 42-109: January-March 1992
This quarterly publication provides archival reports on developments in programs managed by JPL's Office Telecommunications and Data Acquisition (TDA). In space communications, radio navigation, radio science, and ground-based radio and radar astronomy, it reports on activities of the Deep Space Network (DSN) in planning, in supporting research and technology, in implementation, and in operations. Also included is standards activity at JPL for space data and information systems and reimbursable DSN work performed for other space agencies through NASA. The preceding work is all performed for NASA's Office of Space Operations (OSO). The TDA Office also performs work funded by two other NASA program offices through and with the cooperation of the OSO. These are the Orbital Debris Radar Program and 21st Century Communication Studies.
Posner, E. C.↗
Comparative Study of Optical and RF Communication Systems for a Mars Mission - Part II. Unified Value Metrics
In this Par-II report of the Advanced Communications Benefits study, two critical metrics for comparing the benefits of utilizing X-band, Ka-band and Optical frequencies for supporting generic classes of Martian exploration missions have been evaluated.
higher frequencies Neptune mission cost assessment↗
FCS Technology Investigation Overview
This working paper provides an overview of the Future Communication Study (FCS) technology investigation progress. It includes a description of the methodology applied to technology evaluation; evaluation criteria; and technology screening (down select) results. A comparison of screening results with other similar technology screening activities is provided. Additional information included in this working paper is a description of in-depth studies (including characterization of the L-band aeronautical channel; L-band deployment cost assessment; and performance assessments of candidate technologies in the applicable aeronautical channel) that have been conducted to support technology evaluations. The paper concludes with a description on-going activities leading to conclusion of the technology investigation and the development of technology recommendations.
Budinger, James↗
Future Aeronautical Communication Infrastructure Technology Investigation
This National Aeronautics and Space Administration (NASA) Contractor Report summarizes and documents the work performed to investigate technologies that could support long-term aeronautical mobile communications operating concepts for air traffic management (ATM) in the timeframe of 2020 and beyond, and includes the associated findings and recommendations made by ITT Corporation and NASA Glenn Research Center to the Federal Aviation Administration (FAA). The work was completed as the final phase of a multiyear NASA contract in support of the Future Communication Study (FCS), a cooperative research and development program of the United States FAA, NASA, and EUROCONTROL. This final report focuses on an assessment of final five candidate technologies, and also provides an overview of the entire technology assessment process, including final recommendations.
Gilbert, Tricia↗
Status of NASA Goddard Space Flight Center's Participation in SNAP
Dr. Rauscher will present programatic status and high-level/summary information on the technical status of NASA Goddard Space Flight Center's participation in the SuperNova Acceleration Probe (SNAP). Goddard's participation falls into four areas, and status in each of these will be covered. These areas are as follows: (I) focal plane array and packaging, (2) Teledyne HAWAII-4RG sensor chip assembly, (3) communications studies, and (4) integration and test studies.
Rauscher, Bernard↗
Planning and Optimization for Multi-robot Planetary Cave Exploration under Intermittent Connectivity Constraints
Exploring subsurface structures with autonomous robots is of growing interest in the context of planetary caves studies. Communication between robots in these environments is severely degraded which complicates coordination and information distribution. In this paper we focus on planning for mobility and communication in a cave exploration scenario where the situational awareness of a static base station is critical. We propose a notion of information-consistency where a plan itself is part of the information to be shared between robots, and propose a method for generating information-consistent plans. We discuss in detail how the resulting plan can be robustly implemented with minimal communication through local mission executives that run on individual robots. We describe preliminary results on the performance of the planning algorithm and integration of the local mission executives in a high-fidelity simulation environment.
Murray, Richard M.↗