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Benefits and Incentives for ADS-B Equipage in the National Airspace System

Lester, Edward; Hansman, R. John
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Relatório
EN_US
Relevância na Pesquisa
35.96%
Automatic Dependent Surveillance – Broadcast (ADS-B) is a technology that can replace secondary surveillance radars and enhance cockpit situational awareness. It also has the potential to enable procedures not possible with current surveillance technology that would increase the capacity of the National Airspace System (NAS) in the US. Certain forms of ADS-B also have the bandwidth to upload weather and airspace information into the cockpit. However, prior to achieving the benefits of ADS-B, operators must equip with the technology. In order to voluntarily equip, owners and operators must receive benefits from the technology that outweigh the cost or receive other incentives. Through an online survey of stakeholders, applications of ADS-B with the strongest benefits to users are identified. In-cockpit data link offerings are explored in detail, along with a detailed analysis of ADS-B benefits for Hawaiian helicopter operators. The conclusions of this study are that ADS-B should be implemented in non-radar airspace along with busy terminal areas first to gain the most benefits from non-radar separation applications and traffic awareness applications. Also, the basis for the US dual ADS-B link decision is questioned, with a single 1090-ES based link augmented with satellite data link weather recommended.; The authors would like to thank all of interview and survey participants. Without their time and insights...

Building “Situation Awareness” construct from the geometric-functional features of a work environment

CAMILLI, MARCO
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
Relevância na Pesquisa
36.02%
In the last decades, the improvement of technology provided sophisticated systems necessary in “operational environments” where individual and environmental safety is at risk. Most systems acquire information from the environment, detect hazards and spread communications for “operator” support. In the operational environments involving human-systems interaction the operator is usually required to allocate his/her attention for monitoring the systems for long periods. Different sources of information (e.g., external environments or other operators) and its typology (e.g., visual or auditory) are designed in developing “complex systems” in order to solve the work overload problem. In Human Factors / Ergonomics (HF/E) domain the mental workload measure is widely accepted to be the most reliable approach to access both operator functional state (OFS) and human performance factors. However, a further construct named as “Situation Awareness” (SA) has been introduced in order to better understand the OFS in complex environments. Endsley (1995) provided a formal definition of SA as the individuals’ ability to (a) perceive elements in the environment within a volume of time and space, (b) comprehend their meaning, and (c) predict their status in the near future. Although...

Tactical space: beyond line of sight alternatives for the Army and Marine Corps ground tactical warfighter

Luck, Aaron B.; Knight, Anthony G.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
35.95%
Approved for public release; distribution is unlimited.; United States Army and Marine Corps ground tactical warfighters find themselves conducting operations across greater distances and with more autonomy from their higher commands than ever before. As their areas of operations become larger in modern conflicts, and distributed operations become more the norm, deficits in the tactical warfighter?s ability to conduct beyond line of sight (BLOS) communications, intelligence, surveillance, and reconnaissance (ISR), blue force tracking and situational awareness (BFT/SA), and position, navigation, and timing (PNT) become more noticeable and dangerous. The capabilities existing in the tactical space this warfighter operates within and from where he is supported cannot meet his needs now, nor will they likely meet his needs in the future. While upgrades and expansion of current satellite and unmanned aerial system (UAS) architectures will expand these BLOS capabilities, it is not likely they will increase sufficiently to reduce the deficit in support. A new regime, the High Altitude Area of Interest (HAAI) also known as near space, provides potential capabilities specifically tailored to the tactical warfighter. This thesis reviews the BLOS requirements of the tactical warfighter...

LIDAR design for space situational awareness

Gast, David W.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
66.38%
Space Situational Awareness (SSA) is a growing concern for National Security. Among the many methods of increasing SSA is the use of space-based Laser Imaging, Detection And Ranging (LIDAR) sensors to detect, track, classify or image other spacecraft. This Thesis explores the unique trade-spaces and design decisions faced by an engineer designing such a system. It provides an overview of the basic operational principles, the major components, the impact of one design choice on all other decisions, and guidelines for making design choices when designing a space based LIDAR for Space Situational Awareness applications. System operational constraints, demands on the host spacecraft, and potential impacts on other spacecraft are explored. Finally, an illustrative system design is presented, demonstrating the interaction between system requirements, system design, and component selection.

Enhancing space situational awareness using a 3U CubeSat with optical imager

Flanagan, Jason A.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
66.49%
Space situational awareness is extremely important in order to maintain the safety and usability of earth-orbiting satellites, as well as protecting astronauts living and working in space. Traditional space situational awareness is achieved using ground-based radar and optical sensors. This thesis explores the feasibility of space-based space situational awareness using a 3U CubeSat with an optical imager to augment the Space Surveillance Network by capturing conjunctions in space, from which ephemeris data of earth orbiting objects can be updated to more accurately predict future orbital positions. Work completed includes preliminary work towards building, testing, and using a Colony II Bus emulator and interface mechanism, allowing smooth payload and bus integration. Analysis of orbital trajectories for a reference orbit and potential crossing satellites provides insight into the capabilities of the SSA CubeSat. Future work is discussed.

Tailoring systems engineering processes for rapid space acquisitions

Johnson, Kipp M.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
46.1%
The Self-Awareness Space Situational Awareness (SASSA) program is a congressionally initiated technology demonstration program run by the Air Force, Space and Missile System Center (SMC), Los Angeles Air Force Base. Initiated October 2008, SASSA is investigating the feasibility of a highly flexible and adaptable satellite payload system for detecting satellite threats, both natural and manmade. The SASSA program was given cost and schedule limitations with a mandate to deliver hardware for demonstration in 24 months, considered a "rapid acquisition" by AF and SMC standards. This study provides an assessment of how the SASSA program tailored systems engineering processes to implement a "rapid space acquisition." Acquisition and engineering standards define a roadmap for military procurements to produce the most effective product at the most reasonable cost. Refinement of these standards over time is critical to the continued success of acquisition systems to evolve a current and effective military. This study reviews the SASSA concept and technology demonstration, surveys standard systems engineering guidance, catalogues systems engineering processes tailored, and assesses effectiveness of this tailoring. This study will provide observation and assessment of real-world results...

Space-based telescopes for the actionable refinement of ephemeris systems and test engineering

Lozada, Vidal C.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Relevância na Pesquisa
45.95%
This thesis presents the results and activities related to the design, analysis, construction, test, and integration of a flight-qualified satellite, the Space-based Telescopes for the Actionable Refinement of Ephemeris (STARE) satellite. This project has been a collaboration, led by Lawrence Livermore National Laboratory (LLNL) and including the Naval Postgraduate School (NPS) and Texas AandM University. Of particular importance are the processes, experiences, and results of testing the payload and integrated STARE satellite. In addition, an analysis of testing requirements specifically appropriate for CubeSats, has been performed based on experience with larger satellites, and, finally, a thermal model has been developed for on-orbit thermal performance evaluation. The STARE satellite is currently scheduled to be a secondary payload mounted in the NPS CubeSat Launcher (NPSCuL), attached to the Atlas V Aft Bulkhead Carrier (ABC) on the Centaur upper stage. The goal of the STARE project is to improve Space Situational Awareness and, once the concept is validated, to develop a constellation that would be able to deliver highly refined optical data to improve current conjunction analysis.

STARE CubeSat Communications Testing, Simulation and Analysis

Le Gaux, Clyde R.,III
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
45.99%
The Space-based Telescope for the Actionable Refinement of Ephemeris (STARE) CubeSat will play an important role in contributing to this nations space situational awareness (SSA), perhaps one day becoming an integral part of the space surveillance network (SSN) to track orbital debris and satellites, both active and inactive. STARE is a pathfinder mission that is expected to show that CubeSat assets can improve the accuracy of space debris ephemeris data and help national assets avoid conjunction. However, STARE cannot do its job if it cannot communicate effectively with the ground architecture. Knowing the functionality of the on board radio is essential to knowing the capabilities and limitations of the spacecraft. STARE is designed to communicate with the Mobile CubeSat Command and Control (MC3) ground station at the Naval Postgraduate School for data collection and analysis. This thesis shows testing and results, analysis and simulation of the STARE radio and the MC3 ground stations.

A Human Factors Evaluation of the Space Shuttle Cockpit Avionics Upgrade

Westenhaver, Michael S.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
45.95%
During the late 90s, NASA retrofitted the Space Shuttle fleet with a glass cockpit. The new displays replicated legacy formats developed in the 70s, and did not leverage 20 years of display technology and human factors advances. To address this shortcoming the Cockpit Avionics Upgrade (CAU) was initiated to reduce mental workload (MW), increase situational awareness (SA), and enhance performance. Despite the CAU demonstrating improvements in MW, SA, and performance, it was cancelled. Consequently, recorded astronaut data from using the baseline and CAU cockpit configurations was never tied back to cockpit design. This study assesses the CAU design employing human factors principles, evaluates baseline and CAU simulation data, and traces MW and SA differences back to CAU design modifications. Significant improvements were found in all measures and across all conditions. These improvements were found to be greater for ascent scenarios than for entry. From the findings, recommendations for the design and evaluation of future spacecraft cockpits are made.

Building a local Space Situational Awareness (SSA) architecture using hosted payloads

Zaman, Farakh B.
Fonte: Monterey California. Naval Postgraduate School Publicador: Monterey California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
66.23%
Approved for public release; distribution is unlimited; From a military standpoint, space-based capabilities and the need to know what is happening in space, or Space Situational Awareness (SSA), have become invaluable. Current SSA capabilities are expensive and are limited in scope. Hosted payloads however, provide a unique method to provide SSA in a relatively inexpensive manner. This thesis explores the development of an architecture for SSA using hosted payloads. For this thesis, research was conducted on existing systems. NASA and Air Force programs were reviewed to gain an understanding of hosted payloads, and a set of generic high-level requirements were developed for a hosted payload. These requirements will meet the needs of a hosted SSA payload that can enable a larger SSA architecture using hosted payloads. Once the requirements were developed, modeling and simulation using Satellite Tool Kit (STK) was were employed to develop an optimal SSA system using hosted payloads. Finally, once the architecture was defined, an Operational View 1 (OV-1) was developed to provide a graphical representation of the architecture.

Nanosat employment: a theoretical CONOPS for space object identification

Foley, April J.
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
56.02%
Approved for public release; distribution is unlimited; Space Situational Awareness and Space Object Identification are vital to discovering and assessing space-based threats. The current ground-based mission architecture and operational concept do not provide enough detailed information on space objects to give planners and strategists a true picture of the space order of battle. This thesis looks at the possibility of using space-based assets, based on the CubeSat standard, to perform these missions to a higher level of quality. How this system would be folded into the current space systems operational concept is analyzed, as well as some recommendations for further study.

The integration of Situational Awareness Beacon with Reply (SABER) with the Enhanced Position Location Reporting System (EPLRS)

Byrd, Valerie Rosengarn
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Formato: xiv, 73 p.
EN_US
Relevância na Pesquisa
56.31%
Approved for public release; distribution is unlimited; In 1992, The Joint Requirements Oversight Council validated a combat identification mission need statement. In support of the requirement for system interoperability, this thesis proposes a concept of operations for integrating two systems, Situational Awareness Beacon with Reply (SABER) and the Enhanced Position Location Reporting System (EPLRS). Naval Space Command to provide real time combat identification (CID) to the tactical user. It uses UHF satellite communications technology in conjunction with the Global Positioning System (GPS) to provide positioning information for up to 500 users. EPLRS is a situational awareness program used extensively by the U.S. Army to support tactical battlefield operations. In addition to providing automatic friendly identification of EPLRS-equipped units, it has a communications capability that allows for the passage of intelligence and targeting data, messages, and status reports. However, EPLRS operates in a line of sight mode only and uses military grid reference coordinates vice OPS for positional information. The integration of SABER and EPLRS has the potential to serve a major role in the armed services' common goal of reduced fratricide. This thesis gives a detailed description of both systems...

System Self-Awareness and Related Methods for Improving the Use and Understanding of Data within DoD

Zhao, Ying; Mackinnon, Douglas J.; Gallup, Shelley P.
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Relatório
EN_US
Relevância na Pesquisa
46.05%
Data sources for DoD applications often include disparate realtime sensor and archival sources with multiple dimensions, as well as very high rates and very large volumes. The data can include structured data that are of traditional forms (for example, stored in relational databases, Excel, or XML files with well-defined labels with meta-data). Unstructured data can also be included, such as free text, Word, PDF, PowerPoint, and emails. A large percentage of data are unstructured. It remains a daunting task to retain logical integrity of the separate data sources, and support multiple parallel and asynchronous functions of storage, analysis, search, and retrieval of these data sources. Analysts, at present, must manually comb through immense volumes of multisource, multiclassification-level intelligence data to find previously unknown and undiscovered patterns, associations, relationships, trends, and anomalies. This effort can be tedious and slow, and can depend largely upon the individual analyst's experience. Without accurate and timely front-end analysis, link analysis and inferences about future trends are not possible. The authors' methodology cross-examines and considers all of the data to create a full picture...

Space situational awareness CubeSat concept of operations

O'Brien, Tolulope E.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Formato: xviii, 67 p. : ill. (chiefly col.), col. maps. ; 28 cm.
Relevância na Pesquisa
106.42%
The concept of space situational awareness (SSA) is important to preserve manned and unmanned space operations. Traditionally, ground based radar, electro-optical sensors and very limited space-based assets have been used as part of the space surveillance network (SSN) to track orbital debris, inactive and active satellites alike. With the current SSN assets aging and the need for SSA growing, it is important to explore new ways to ensure proper SSA is maintained to preserve space operations. The Space-based Telescope for the Actionable Refinement of Ephemeris (STARE) project was initiated to explore the potential for a cube satellite (CubeSat) to contribute to the current SSN, with an optical payload integrated into a 3U Colony II Bus. The bus and payload data from the CubeSat will be collected by the Naval Postgraduate School Mobile CubeSat Command and Control ground station. Telemetry data from the bus will be analyzed at NPS and the payload data at Lawrence Livermore National Laboratory. This thesis outlines the concept of operation for the STARE CubeSat and investigates the possibility of using the data generated by STARE to augment the SSN to reduce the errors associated with conjunction analysis performed at the Joint Space Operations Center.; US Navy (USN) author

Geosynchronous orbit determination using space surveillance network observations and improved radiative force modeling

Lyon, Richard Harry, 1981-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 375 p.; 15406341 bytes; 15450515 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
45.99%
Correct modeling of the space environment, including radiative forces, is an important aspect of space situational awareness for geostationary (GEO) spacecraft. Solar radiation pressure has traditionally been modeled using a rotationally-invariant sphere with uniform optical properties. This study is intended to improve orbit determination accuracy for 3-axis stabilized GEO spacecraft via an improved radiative force model. The macro-model approach, developed earlier at NASA GSFC for the Tracking and Data Relay Satellites (TDRSS), models the spacecraft area and reflectivity properties using an assembly of flat plates to represent the spacecraft components. This 'box-wing' approach has been adapted for the UNIX version of the Goddard Trajectory Determination System (GTDS) at the MIT/Lincoln Laboratory. This thesis presents background and mathematical development of the macro-model approach. This thesis also describes software development and testing, including incorporation of a one-panel spacecraft model along with the full macro-model. A model for Earth albedo and Earth infrared radiation and related software development is also described. Additionally, this thesis gives details about the TDRSS macro-model, and explains the development of a macro-model for the NASA Geosynchronous Operational Environmental Satellites (GOES) I-M spacecraft. Results of simulated data testing using the improved radiative force models are presented. The real data testing detailed in this thesis is an investigation into improving GEO orbit determination using the new force models along with observation data from the Space Surveillance Network (SSN). For the TDRSS spacecraft...

Innovative observing strategy and orbit determination for Low Earth Orbit Space Debris

Milani, Andrea; Farnocchia, Davide; Dimare, Linda; Rossi, Alessandro; Bernardi, Fabrizio
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.99%
We present the results of a large scale simulation, reproducing the behavior of a data center for the build-up and maintenance of a complete catalog of space debris in the upper part of the low Earth orbits region (LEO). The purpose is to determine the performances of a network of advanced optical sensors, through the use of the newest orbit determination algorithms developed by the Department of Mathematics of Pisa (DM). Such a network has been proposed to ESA in the Space Situational Awareness (SSA) framework by Carlo Gavazzi Space SpA (CGS), Istituto Nazionale di Astrofisica (INAF), DM, and Istituto di Scienza e Tecnologie dell'Informazione (ISTI-CNR). The conclusion is that it is possible to use a network of optical sensors to build up a catalog containing more than 98% of the objects with perigee height between 1100 and 2000 km, which would be observable by a reference radar system selected as comparison. It is also possible to maintain such a catalog within the accuracy requirements motivated by collision avoidance, and to detect catastrophic fragmentation events. However, such results depend upon specific assumptions on the sensor and on the software technologies.

On the detection and tracking of space debris using the Murchison Widefield Array. I. Simulations and test observations demonstrate feasibility

Tingay, S. J.; Kaplan, D. L.; McKinley, B.; Briggs, F.; Wayth, R. B.; Hurley-Walker, N.; Kennewell, J.; Smith, C.; Zhang, K.; Arcus, W.; Bhat, R.; Emrich, D.; Herne, D.; Kudryavtseva, N.; Lynch, M.; Ord, S. M.; Waterson, M.; Barnes, D. G.; Bell, M.; Gaens
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/08/2013
Relevância na Pesquisa
46%
The Murchison Widefield Array (MWA) is a new low frequency interferomeric radio telescope. The MWA is the low frequency precursor to the Square Kilometre Array (SKA) and is the first of three SKA precursors to be operational, supporting a varied science mission ranging from the attempted detection of the Epoch of Reionisation to the monitoring of solar flares and space weather. We explore the possibility that the MWA can be used for the purposes of Space Situational Awareness (SSA). In particular we propose that the MWA can be used as an element of a passive radar facility operating in the frequency range 87.5 - 108 MHz (the commercial FM broadcast band). In this scenario the MWA can be considered the receiving element in a bi-static radar configuration, with FM broadcast stations serving as non-cooperative transmitters. The FM broadcasts propagate into space, are reflected off debris in Earth orbit, and are received at the MWA. The imaging capabilities of the MWA can be used to simultaneously detect multiple pieces of space debris, image their positions on the sky as a function of time, and provide tracking data that can be used to determine orbital parameters. Such a capability would be a valuable addition to Australian and global SSA assets...

The Fabra-ROA Telescope at Montsec (TFRM): A Fully Robotic Wide-field Telescope for Space Surveillance and Tracking

Montojo, F. J.; Fors, O.; Muinos, J. L.; Nunez, J.; Lopez-Morcillo, R.; Baena, R.; Boloix, J.; Lopez-Moratalla, T.; Merino, M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 27/09/2011
Relevância na Pesquisa
46.02%
Since the beginning of the Space Age optical sensors have been one of the main instruments for positioning and tracking known space objects. Nowadays, the unrelenting growth of man-made objects together with the overcrowding of the useful satellite orbits, and the real space debris and NEO hazards, has made necessary to carry out surveys of the space looking for uncatalogued objects. Optical telescopes play a key role in the Space Surveillance and Tracking (SST) as a primary Space Situational Awareness element and, it is known, that the best instrument for this task is a fully robotic wide-field telescope with a minimum aperture of 40cm. The Baker-Nunn Cameras (BNCs) were produced by the Smithsonian Institution during the late 50s as an optical tracking system for artificial satellites. These wide-field telescopes of 50cm of aperture were manufactured by Perkin- Elmer (optics) and Boller & Chivens (mechanics) with the highest quality specifications. The TFRM is a fully robotic refurbished BNC that exploits the excellent mechanical and optical original design to obtain an equatorial telescope with a useful 4.4{\deg}x4.4{\deg} CCD field of view. TFRM is therefore a European asset very well suited for SST (satellites and space debris) and NEO observations. Moreover...

An Event Based Approach To Situational Representation

Ashish, Naveen; Kalashnikov, Dmitri; Mehrotra, Sharad; Venkatasubramanian, Nalini
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/06/2009
Relevância na Pesquisa
36.01%
Many application domains require representing interrelated real-world activities and/or evolving physical phenomena. In the crisis response domain, for instance, one may be interested in representing the state of the unfolding crisis (e.g., forest fire), the progress of the response activities such as evacuation and traffic control, and the state of the crisis site(s). Such a situation representation can then be used to support a multitude of applications including situation monitoring, analysis, and planning. In this paper, we make a case for an event based representation of situations where events are defined to be domain-specific significant occurrences in space and time. We argue that events offer a unifying and powerful abstraction to building situational awareness applications. We identify challenges in building an Event Management System (EMS) for which traditional data and knowledge management systems prove to be limited and suggest possible directions and technologies to address the challenges.

Mixture Modeling based Probabilistic Situation Awareness

Liu, Bin
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.96%
The problem of situational awareness (SAW) is investigated from the probabilistic modeling point of view. Taking the situation as a hidden variable, we introduce a hidden Markov model (HMM) and an extended state space model (ESSM) to mathematically express the dynamic evolution law of the situation and the relationships between the situation and the observable quantities. We use the Gaussian mixture model (GMM) to formulate expert knowledge, which is needed in building the HMM and ESSM. We show that the ESSM model is preferable as compared with HMM, since using ESSM, we can also get a real time estimate of the pivot variable that connects the situation with the observable quantities. The effectiveness and efficiency of both models are tested through a simulated experiment about threat surveillance.; Comment: 14 pages, 6 figures