Manual Gridding of DRIR Facsimile Pictures
Method for manual geographical referencing of direct readout infrared radiometer data from Nimbus C satellite
NIMBUS SATELLITE↗
SEARCH · Engineering Papers
Results for “reference systems”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Derivation and statistical comparison of various analytical techniques which define the location of reference horizons in the earth's horizon radiance profile
Analytical methods defining location of reference horizons in earth horizon radiance profile
SPACECRAFT INSTRUMENTATION↗
Control of linear plants with zeros and slowly varying parameters.
Reduction of order technique pertaining to plant and reference model in controller design for linear plants transfer functions with zeros and slowly varying parameters
REFERENCE SYSTEM↗
Differential correction of non-Keplerian reference orbits.
Differential correction vectors for non-Keplerian reference orbits, reexamining rotating ellipses in Hansen type intermediaries
STATE VECTOR↗
Interplanetary guidance system requirements study. Volume 2 - Computer program description. Part 4 - Performance assessment for all inertial guidance systems
Digital computer program for performance analysis of all inertial guidance system along reference trajectories
Source record↗
Equipment-tolerant range code demodulation method - A concept
Demodulation loop of automatic range-measuring system uses reference signal wave of locally generated pseudo-noise plus square wave of same period as the clock. Phase instabilities in IF amplifiers appear only as gain changes in the loop, and do not cause errors in range determination.
Welter, N.↗
Hybrid holographic system using reflected and transmitted object beams simultaneously Patent
Hybrid holographic system using reference, transmitted, and reflected beams simultaneously
Kurtz, R. L.↗
Heat source reentry vehicle design study
The design details are presented of a flight-type heat source reentry vehicle and heat exchanger compatible with the isotope Brayton power conversion system. The reference reentry vehicle and heat exchanger were modified, orbital and superorbital capability was assessed, and a complete set of detail design layout drawings were provided.
Ryan, R. L.↗
The behavior of magnitude dependent systematic errors
The objective grating technique is discussed. From the investigation of actual material, it is established that the effect of coma varies significantly from plate to plate, also that a model linear in diameter and/or coordinate may be inadequate for its removal, and even introduce systematic errors. From this standpoint, the requirements of reference star systems are discussed.
Eichhorn, H.↗
Three-D multilateration: A precision geodetic measurement system
A technique of satellite geodesy for determining the relative three dimensional coordinates of ground stations within one centimeter over baselines of 20 to 10,000 kilometers is discussed. The system is referred to as 3-D Multilateration and has applications in earthquake hazard assessment, precision surveying, plate tectonics, and orbital mechanics. The accuracy is obtained by using pulsed lasers to obtain simultaneous slant ranges between several ground stations and a moving retroreflector with known trajectory for aiming the lasers.
Escobal, P. R.↗
Design implementation and control of MRAS error dynamics
Use is made of linearized error characteristic equation for model-reference adaptive systems to determine a parameter adjustment rule for obtaining time-invariant error dynamics. Theoretical justification of error stability is given and an illustrative example included to demonstrate the utility of the proposed technique.
Colburn, B. K.↗
Pioneer Jupiter Orbiter/Probe mission. II - Atmospheric Probe design considerations
Probe design considerations for a 1981 Pioneer Jupiter Orbiter/Probe mission are summarized. Extensive engineering analysis, design, and proof-of-concept testing of a reference probe system developed during the past three years are reviewed. Mission compatibility, science measurements, environmental characteristics, spacecraft interfaces, subsystem constraints, technology development, and programmatic factors are reviewed and discussed. It is demonstrated that for a low-entry-angle, daylight mission to Jupiter a 150 kg semiautonomous entry probe system utilizing state of the art technology is compatible with all the requirements.
Bradley, F. E.↗
Design study of a HEAO-C spread spectrum transponder telemetry system for use with the TDRSS subnet
The results of a design study of a spread spectrum transponder for use on the HEAO-C satellite were given. The transponder performs the functions of code turn-around for ground range and range-rate determination, ground command receiver, and telemetry data transmitter. The spacecraft transponder and associated communication system components will allow the HEAO-C satellite to utilize the Tracking and Data Relay Satellite System (TDRSS) subnet of the post 1978 STDN. The following areas were discussed in the report: TDRSS Subnet Description, TDRSS-HEAO-C System Configuration, Gold Code Generator, Convolutional Encoder Design and Decoder Algorithm, High Speed Sequence Generators, Statistical Evaluation of Candidate Code Sequences using Amplitude and Phase Moments, Code and Carrier Phase Lock Loops, Total Spread Spectrum Transponder System, and Reference Literature Search.
Weathers, G.↗
Extended Lyapunov stability criterion using a nonlinear algebraic relation with application to adaptive control
A new nonlinear stability criterion is developed by use of a class of Lyapunov functionals for model-reference adaptive systems (MRAS). Results are compared with traditional results, and a comparative design technique is used to illustrate its function in improving the transient response of an MRAS controller. For a particular system structure and class of input signals, the new stability criterion is shown to include traditional sufficiency stability conditions as a special case. An example is cited to illustrate the use of the nonlinear criterion and its definite advantages in helping improve the adaptive error transient response of a system. Analysis of results is effected by use of a linearization technique on the resulting adaptive equations.
Colburn, B. K.↗
Improved gravity field and station-coordinate estimates from laser tracking data
Knowledge of the long-wavelength features of the geopotential and the geocentric coordinates of satellite-tracking stations is significantly improved by the use of precision satellite tracking with lasers. Tracking data on nine satellites are combined with terrestrial gravimetry to obtain a spherical-harmonics representation of the geopotential complete through degree and order 24. Laser tracking data are used to determine the coordinates of tracking stations. This coordinate system is referred to an inertial reference frame by use of camera observations and observations of deep-space probes. Resulting geodetic parameters provide better satellite ephemerides and a reference for analyzing satellite-to-sea-surface altimetry.
Gaposchkin, E. M.↗
Low-power anemometer
Device allows wind speeds to be measured with less power by alternating hot-wire or hot-film heating periods with measurement periods. System includes reference auxiliary circuits to generate V sub ref and ramp voltage (E sub 3) and reference half of bridge circuit. Circuit permits use of several sensing films with common temperature compensation sensor.
Gilje, R. I.↗
ANOPP programmer's reference manual for the executive System
Documentation for the Aircraft Noise Prediction Program as of release level 01/00/00 is presented in a manual designed for programmers having a need for understanding the internal design and logical concepts of the executive system software. Emphasis is placed on providing sufficient information to modify the system for enhancements or error correction. The ANOPP executive system includes software related to operating system interface, executive control, and data base management for the Aircraft Noise Prediction Program. It is written in Fortran IV for use on CDC Cyber series of computers.
Gillian, R. E.↗
SUTIL: system utilities routines programmer's reference manual
A package of FORTRAN callable subroutines which allows efficient communication of data between users and programs is described. Proper utilization of the SUTIL package to reduce program core requirements and expedite program development is emphasized.
Harper, D.↗