386 research outputs found

    Impacts of Anti-Access/Area Denial Measures on Space Systems: Issues and Implications for Army and Joint Forces

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    The 2018 National Defense Strategy and National Space Strategy both reaffirm the vital interests that the United States has in the domain of space. However, space remains an inherently hostile environment that has become congested, contested, and competitive among the nations. What are ways for the U.S. Army to assure the success of its space-dependent warfighting functions in an anti-access/area denial (A2/AD) environment where space systems are degraded for significant periods of time?https://press.armywarcollege.edu/monographs/1395/thumbnail.jp

    Virtual SATCOM, Long Range Broadband Digital Communications

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    The current naval strategy is based on a distributed force, networked together with high-speed communications that enable operations as an intelligent, fast maneuvering force. Satellites, the existing network connector, are weak and vulnerable to attack. HF is an alternative, but it does not have the information throughput to meet the distributed warfighting need. The US Navy does not have a solution to reduce dependency on space-based communication systems while providing the warfighter with the required information speed. Virtual SATCOM is a solution that can match satellite communications (SATCOM) data speed without the vulnerable satellite. It is wireless communication on a High Frequency (HF) channel at SATCOM speed. We have developed an innovative design using high power and gain, ground-based relay systems. We transmit extremely wide-wideband HF channels from ground stations using large directional antennas. Our system starts with a highly directional antenna with a narrow beam that enables increased bandwidth without interfering with other spectrum users. The beam focus and power provide a high SNR across a wideband channel with data rates of 10 Mbps; 1000 times increase in HF data speed. Our modeling of the ionosphere shows that the ionosphere has more than adequate bandwidth to communicate at 3000 km and high speeds while avoiding detection. We designed a flexible structure adjustable to the dynamic ionosphere. Our design provides a high-speed communications path without the geo-location vulnerability of legacy HF methods. Our invention will benefit mobile users using steerable beam forming apertures with wide bandwidth signals. This dissertation will focus on three areas: an examination of the ionosphere’s ability to support the channel, design of a phased array antenna that can produce the narrow beam, and design of signal processing that can accommodate the wideband HF frequency range. Virtual SATCOM is exciting research that can reduce cost and increase access to long-range, high data rate wireless communications

    Internet Protocol (IP) Over Link-16

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    The purpose of Link- 16 is to exchange real-time tactical data among units of the United States and allied forces. Primary Link- 16 functions include exchange of friendly unit position and status data, fl%the dissemination of tactical surveillance track data, and the control/management of air, surface, and subsurface engagements. Because Link- 16 will play an integral role in fl% network-centric Joint Battlespace Infosphere (JBI), the performance of Internet Protocol version six (IPv6) and IP Security (IPSec) over Link-16 needs to be determined. Using OPNET modeling software to simulate a Link- 16 network, the investigation of this research revealed that the overhead from IPv6 and IPSec does not significantly affect end-to-end delay and effective throughput of the Link- 16 network. As long as the encryption and authentication protocols are preprocessed, these protocols add minimal amounts of latency overhead to the Link- 16 network. However, as the offered load is extended beyond the 90% level, the overhead from the IPSec extensions begins to have more of a negative effect on the End-to-End delay and throughput. Therefore, as the offered load increases beyond the 90% level, it begins to have a significant impact act on the performance of the Link- 16 network

    Modellierung und Evaluierung der “Required Communication Performance” von Luft-Boden Datenverbindungen mit “Erasure Codes”.

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    In this work, a model to calculate the air-ground data link performance using the “Required Communication Performance” metric used in aviation is proposed. This model is applied to evaluate the performance of data links and to estimate the minimum link performance required to meet the safety requirements. The results show that it is highly unlikely that air-ground data links achieve the minimum performance. “Erasure codes” and a multiple link concept are proposed and evaluated to improve the performance of the links.Diese Arbeit beschreibt ein Modell, mit welcher die Leistung von Luft-Boden Datenverbindungen unter Verwendung der in der Luftfahrt verwendeten Metrik „Required Communication Performance“, berechnet werden. Dieses Modell wird angewendet, um die Leistung von Datenverbindungen zu bewerten und die minimale Verbindungsleistung abzuschätzen, die erforderlich ist, um die Sicherheitsanforderungen zu erfüllen. Die Ergebnisse zeigen, dass es sehr unwahrscheinlich ist, dass Luft-Boden Datenverbindungen die Mindestleistung erreichen. Zur Verbesserung der Leistung der Links werden Konzepte basierend auf “Erasure Codes" und mehreren Links vorgeschlagen und evaluiert

    An overview of the Copernicus C4I architecture

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    The purpose of this thesis is to provide the reader with an overview of the U.S. Navy's Copernicus C4I Architecture. The acronym "C4I" emphasizes the intimate relationship between command, control, communications and intelligence, as well as their significance to the modern day warrior. Never in the history of the U.S> Navy has the importance of an extremely flexible C4I architecture been made more apparent than in the last decade. Included are discussions of the Copernicus concept, its command and control doctrine, its architectural goals and components, and Copernicus-related programs. Also included is a discussion on joint service efforts and the initiatives being conducted by the U.S. Marine Corps, the U.S. Air Force and the U.S. Army. Finally, a discussion of the Copernicus Phase I Requirements Definition Document's compliance with the acquisition process as required by DoD Instruction 5000.2 is presented.http://archive.org/details/overviewofcopern00dearLieutenant, United States NavyApproved for public release; distribution is unlimited

    Aeronautics and space report of the President, 1982 activities

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    Achievements of the space program are summerized in the area of communication, Earth resources, environment, space sciences, transportation, aeronautics, and space energy. Space program activities of the various deprtments and agencies of the Federal Government are discussed in relation to the agencies' goals and policies. Records of U.S. and world spacecraft launchings, successful U.S. launches for 1982, U.S. launched applications and scientific satellites and space probes since 1975, U.S. and Soviet manned spaceflights since 1961, data on U.S. space launch vehicles, and budget summaries are provided. The national space policy and the aeronautical research and technology policy statements are included

    NASA compendium of satellite communications programs

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    A comprehensive review is given of worldwide satellite communication programs that range in time from the inception of satellite communications to mid-1974. Particular emphasis is placed on program results, including experiments conducted, communications system operational performance, and technology employed. The background for understanding these results is established through brief summaries of the program organization, system configuration, and satellite and ground terminal characteristics. Major consideration is given to the communications system aspects of each program, but general spacecraft technology and other experiments conducted as part of the same program are mentioned summarily

    U.S. Unmanned Aerial Vehicles (UAVS) and Network Centric Warfare (NCW) impacts on combat aviation tactics from Gulf War I through 2007 Iraq

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    Unmanned, aerial vehicles (UAVs) are an increasingly important element of many modern militaries. Their success on battlefields in Afghanistan, Iraq, and around the globe has driven demand for a variety of types of unmanned vehicles. Their proven value consists in low risk and low cost, and their capabilities include persistent surveillance, tactical and combat reconnaissance, resilience, and dynamic re-tasking. This research evaluates past, current, and possible future operating environments for several UAV platforms to survey the changing dynamics of combat-aviation tactics and make recommendations regarding UAV employment scenarios to the Turkish military. While UAVs have already established their importance in military operations, ongoing evaluations of UAV operating environments, capabilities, technologies, concepts, and organizational issues inform the development of future systems. To what extent will UAV capabilities increasingly define tomorrow's missions, requirements, and results in surveillance and combat tactics? Integrating UAVs and concepts of operations (CONOPS) on future battlefields is an emergent science. Managing a transition from manned- to unmanned and remotely piloted aviation platforms involves new technological complexity and new aviation personnel roles, especially for combat pilots. Managing a UAV military transformation involves cultural change, which can be measured in decades.http://archive.org/details/usunmannedaerial109454211Turkish Air Force authors.Approved for public release; distribution is unlimited

    Identification of Technologies for Provision of Future Aeronautical Communications

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    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

    Joint All Domain Command & Control (JADC2) Naval Analysis

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    NPS NRP Technical ReportThe Navy needs to play a vital role in JADC2 and to serve as a central pillar. Leveraging extensive knowledge of agile C2 and rapid organization reconfiguration, along with experience with mission command and C2 knowledge flow integration, this project seeks to address questions regarding how the Navy should prepare for this role; how naval fires and assets should cross COCOMs; how the Navy Tactical Grid should integrate into the Joint Grid; and how Service unique knowledge needs and capabilities should balance with important goals of convergence, commonality and interoperability.N2/N6 - Information WarfareThis research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE 0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.
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