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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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State of randomly excited dynamical system estimated from noise measurements having finite duration, and optimal linear filter synthesized from conditional probability theory
Digital filters for non-real time data processing
Data compression with digital filtering by fan method and step reduction method
Automatic dielectric film filter method in spectrophotometry
Kalman filter alternate form extended to include multiple simultaneous correlated measurements, testing with ballistic model and using square root formulation for trajectory determination
Filtering for nonlinear dynamical systems with white Gaussian noise processes
Kalman filter alternate form extended to include multiple simultaneous correlated measurements, testing with ballistic model and using square root formulation for trajectory determination
Finite dimensional approximations of optimal nonlinear filters for class of large-noise, nonlinear, continuous-time problems
Error effect in continuous Kalman filters used in orbit determination problems, deriving error bounds formula
Spectral irradiances determined by conventional prism monochromator and by system employing narrow bandpass interference filters
This paper discusses the Instrument Pointing Frame (IPF) Kalman Filter, which is an algorithm developed for focal plane calibration of NASA's Space Infrared Telescope Facility (SIRTF).
This paper describes the design and initial test results of an extended Kalman filter that has been developed at Jet Propulsion Laboratory (JPL) for post-flight reconstruction of the trajectory and attitude history of a spacecraft entering a planetary atmosphere and descending upon a parachute.
A Kalman filter has many properties that make it an attractive choice as a technique for combining Earth orientation measurements. It allows the full accuracy of the measurements to be used, whether the measurements are degenerate or are of full rank, are irregularly or regularly spaced in time, or are corrupted by systematic or other errors that can be described by stochastic models.
A new technology, developed at JPL, using low-absorption color filters and color recycling system, is able to enhance the efficiency of current liquid crystal device up to 500 percent.
A new technology invented at JPL of color filtering and beam scanning device based on electro-optical switching of internal-reflection states have been proposed for use in DWDM, display and measurement applications.
Liquid crystal tunable filters are useful in building compact multi-spectral instruments. The system is portable and adaptable for use in a variety of fields of study in the visible and near-infrared regions of the spectrum.We will present data from calibration targets and some applications, results of the spectral calibration of a spectrometer system, and results of environmental (vibration, radiation, shock, and thermal) testing. Data acquisition and system design are also discussed.
An approximate Kalman filter and smoother, based on approximations of the state estimation error covariance matrix, is described. Approximations include a reduction of the effective state dimension, use of a static asymptotic error limit, and a time-invariant linearization of the dynamic model for error integration. The approximations lead to dramatic computational savings in applying estimation theory to large complex systems. Examples of use come from TOPEX/POSEIDON.
The Jet Propulsion Laboratory Kalman Earth Orientation Filter (KEOF) uses several of the Earth rotation data sets available to generate optimally interpolated UT1 and LOD series to support spacecraft navigation. This paper compares use of various data sets within KEOF.