ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Other Sources  (3,097)
  • AERODYNAMICS  (2,110)
  • COMMUNICATIONS AND RADAR  (987)
  • 1975-1979  (3,097)
  • 1
    facet.materialart.
    Unknown
    The use of geostationary platforms for future U.S. domestic satellite communications (1979)
    In:  Other Sources
    Details
    Publication Date: 2019-08-28
    Description: Quantitative analyses of the relative costs and utilization of the available geostationary orbital arc and radio spectrum allocations between large spacecraft platforms and future individual satellites used for communications in the U.S. and the Atlantic Basin are presented. Attention is given to the high capacity and the switching capabilities of the platforms, and the frequency ranges (6/4, 14/12, and 30/20 GHz) at which they can operate. In addition, characteristics of conventional satellites, earth station design, and the connectivity of satellite systems are discussed.
    Keywords: COMMUNICATIONS AND RADAR
    Type: In: ICC ''79; International Conference on Communications; Jun 10, 1979 - Jun 14, 1979; Boston, MA
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    On wings of circular design (1979)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: Prandtl's method of sources and sinks for air foils is used to investigate the aerodynamics of circular wings in constant flow. Lift distribution, total lift, and pitching moment are investigated as well as the influence of changes in the angle of attack.
    Keywords: AERODYNAMICS
    Type: NASA-TM-75505
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Solution of a few nonlinear problems in aerodynamics by the finite elements and functional least squares methods (1979)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: The numerical simulation of the transonic flows of idealized fluids and of incompressible viscous fluids, by the nonlinear least squares methods is presented. The nonlinear equations, the boundary conditions, and the various constraints controlling the two types of flow are described. The standard iterative methods for solving a quasi elliptical nonlinear equation with partial derivatives are reviewed with emphasis placed on two examples: the fixed point method applied to the Gelder functional in the case of compressible subsonic flows and the Newton method used in the technique of decomposition of the lifting potential. The new abstract least squares method is discussed. It consists of substituting the nonlinear equation by a problem of minimization in a H to the minus 1 type Sobolev functional space.
    Keywords: AERODYNAMICS
    Type: NASA-TM-75732
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    Big Comsats for big jobs at low user cost (1979)
    In:  Other Sources
    Details
    Publication Date: 2019-08-28
    Description: Three examples are used to illustrate what is possible with large space systems: (1) personal communications using wrist telephones, (2) electronic transmission of mail, and (3) wide dissemination of educational TV. Design concepts and costs are explored and compared to alternative ground-based concepts.
    Keywords: COMMUNICATIONS AND RADAR
    Type: Astronautics and Aeronautics; 17; Feb. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    Terrestrial/land mobile satellite considerations, NASA plans and critical issues (1979)
    In:  Other Sources
    Details
    Publication Date: 2019-08-28
    Description: This paper briefly reviews the land mobile market and discusses services that might be provided by hybrid terrestrial/land mobile satellite systems (T/LMSS). In view of the expected urban/suburban patterns of planned terrestrial systems it is suggested that a satellite may prove a cost-effective complement to terrestrial systems for serving thinly populated or large geographical areas. A basic Land Mobile Satellite Service (LMSS) is described, example applications are provided, and the status and rationale for LMSS frequencies in the 806-890 MHz band is given. Next, examples are given of NASA supported land mobile satellite experiments and a preliminary T/LMSS work plan, part of an overall Narrowband Program, is presented for structuring future work. The initiation of the T/LMSS plan depends on pending management/budget decisions. The report closes with a listing of issues and potential problem areas, the solutions of which NASA believes are critical to the success of the proposed T/LMSS effort.
    Keywords: COMMUNICATIONS AND RADAR
    Type: NTC ''79; National Telecommunications Conference; Nov 27, 1979 - Nov 29, 1979; Washington, DC
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unknown
    An overview of the NASA satellite communications program (1979)
    In:  Other Sources
    Details
    Publication Date: 2019-08-28
    Description: This overview sets the framework for five descriptive papers from NASA Field Centers where satellite communications research and development is being conducted. A review of events of 1973-78 in the Federal Government, in industry, and in professional organizations are shown to have contributed to the formulation of new policy supporting the establishment of renewed efforts within NASA toward improved use of the spectrum and orbit for communications. The work will focus on the development of 'frequency re-use' technology, including multi-beam antennas and on-board switching for future spacecraft. This paper treats the planning issues and the approaches taken toward forming a coherent program from the sustaining efforts of the recent past. Companion papers highlight the methods, the technology, and the activities that are assisting in the transition to a new program.
    Keywords: COMMUNICATIONS AND RADAR
    Type: In: ICC ''79; International Conference on Communications; Jun 10, 1979 - Jun 14, 1979; Boston, MA
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unknown
    Simulation program of nonlinearities applied to telecommunication systems (1979)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: In any satellite communication system, the problems of distorsion created by nonlinear devices or systems must be considered. The subject of this paper is the use of the Fast Fourier Transform (F.F.T.) in the prediction of the intermodulation performance of amplifiers, mixers, filters. A nonlinear memory-less model is chosen to simulate amplitude and phase nonlinearities of the device in the simulation program written in FORTRAN 4. The experimentally observed nonlinearity parameters of a low noise 3.7-4.2 GHz amplifier are related to the gain and phase coefficients of Fourier Service Series. The measured results are compared with those calculated from the simulation in the cases where the input signal is composed of two, three carriers and noise power density.
    Keywords: COMMUNICATIONS AND RADAR
    Type: NASA-TM-75511 , CNES-NT-81
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 8
    facet.materialart.
    Unknown
    Aircraft icing: Introduction (1979)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: The objectives of the Workshop were as follows: (1) to assess the current understanding of fixed wing and rotorcraft operational icing environments and problems (2) to evaluate facilities requirements for R&D and certification purposes (3) to examine means of improving icing forecasts (4) to identify shortcomings in aeronautical icing knowledge which can be alleviated by new research and instrumentation development.
    Keywords: AERODYNAMICS
    Type: NASA. Lewis Res. Center Aircraft Icing; 3 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 9
    facet.materialart.
    Unknown
    A set of satellite experiments for studying the magnetosphere-ionosphere communications (1978)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: Magnetospheric substorms are one of the basic problems in the physics of near earth space. They appear as magnetic and ionospheric perturbations, disturbances in radio communication, polar auroras and electromagnetic radiation in different frequency ranges. These phenomena were studied from single satellites. However, it is impossible to study these phenomena adequately without simultaneous measurements from at least two different positions with identical instruments. A suitable program can be developed based on the Interkosmos work using new achievements in electronics.
    Keywords: COMMUNICATIONS AND RADAR
    Type: NASA-TM-75563 , PR-290
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 10
    facet.materialart.
    Unknown
    A multilevel system of algorithms for detecting and isolating signals in a background of noise (1978)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: Signal information is processed with the help of algorithms, and then on the basis of such processing, a part of the information is subjected to further processing with the help of more precise algorithms. Such a system of algorithms is studied, a comparative evaluation of a series of lower level algorithms is given, and the corresponding algorithms of higher level are characterized.
    Keywords: COMMUNICATIONS AND RADAR
    Type: NASA-TM-75541 , PR-276
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...