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Data processing of lunar infrared measurements at high spatial and radiometric resolution to obtain brightness temperatures
The Multiple Experiment Transporter into Earth Orbit and Return-Solar EUV Experiment (METEOR-SEE) project will take daily extreme ultraviolet (EUV) irradiance spectra starting in the summer of 1995. The METEOR-SEE package consists of an EUV grating spectrograph (EGS) and a cluster of 5 soft x-ray photometers (XP's). Both these instruments have flown previously on NASA sounding rockets. Because of the scope of the project, new data processing algorithms had to be developed for the SEE instruments onboard the METEOR satellite. An overview of the data flow describes how satellite data are collected and processed. Detailed descriptions of specific routines will show what data processing entails.
Computer program PACER-65, is used for flowsheet calculations and easily adapted to process data reduction. Each unit, vessel, meter, and processing operation in the overall flowsheet is represented by a separate subroutine, which the program calls in the order required to complete an overall flowsheet calculation.
Optical data processing and reduction, coherent optical correlators, and correlation analysis of holograms
A model is considered for vehicle-borne parallel optical data processing which might be used as a key part of an advanced earth resources satellite mission. Some typical applications and the operation of the on-board processor are discussed.
The expert system technology is focused on as a data processing tool. Several existing applications are analyzed. Their original definition as pure expert systems is contrasted with their current status as integrated systems. The architectural requirements needed to support such a heterogeneous environment are given.
The complete set of Tropical Ocean and Global Atmosphere (TOGA)/Coupled Ocean Atmosphere Response Experiment (COARE) flight data for the 91.65 GHz Airborne Meteorological Radiometer (AMMR92) contains data from nineteen flights: two test flights, four transit flights, and thirteen experimental flights. The data flight occurred between December 16, 1992 and February 28, 1993. Data collection from the AMMR92 during the first ten flights of TOGA/COARE was performed using the executable code TSK30041. These are IBM PC/XT programs used by the NASA Goddard Space Flight Center (GSFC). During one flight, inconsistencies were found during the operation of the AMMR92 using the GSFC data acquisition system. Consequently, the Georgia Tech (GT) data acquisition system was used during all successive TOGA/COARE flights. These inconsistencies were found during the data processing to affect the recorded data as well. Errors are caused by an insufficient pre- and post-calibration setting period for the splash-plate mechanism. The splash-plate operates asynchronusly with the data acquisition system (there is no position feedback to the GSFC or GT data system). This condition caused both the calibration and the post-calibration scene measurement to be corrupted on a randomly occurring basis when the GSFC system was used. This problem did not occur with the GT data acquisition system due to sufficient allowance for splash-plate settling. After TOGA/COARE it was determined that calibration of the instrument was a function of the scene brightness temperature. Therefore, the orientation error in the main antenna beam of the AMMR92 is hypothesized to be caused by misalignment of the internal 'splash-plate' responsible for directing the antenna beam toward the scene or toward the calibration loads. Misalignment of the splash-plate is responsible for 'scene feedthrough' during calibration. Laboratory investigation at Georgia Tech found that each polarization is affected differently by the splash-plate alignment error. This is likely to cause significant and unique errors in the absolute calibration of each channel.
A selection of NASA Earth observations programs are reviewed, emphasizing hardware capabilities. Sampling theory, noise and detection considerations, and image evaluation are discussed for remote sensor imagery. Vision and perception are considered, leading to numerical image processing. The use of multispectral scanners and of multispectral data processing systems, including digital image processing, is depicted. Multispectral sensing and analysis in application with land use and geographical data systems are also covered.
The methodology used in the compilation and synthesis of baseline science requirements associated with the 30 + EOS (Earth Observing System) instruments and over 2,400 EOS data products (both output and required input) proposed by EOS investigators is discussed. A brief background on EOS and the EOS Data and Information System (EOSDIS) is presented, and the approach is outlined in terms of a multilayer model. The methodology used to compile, synthesize, and tabulate requirements within the model is described. The principal benefit of this approach is the reduction of effort needed to update the analysis and maintain the accuracy of the science data processing requirements in response to changes in EOS platforms, instruments, data products, processing center allocations, or other model input parameters. The spreadsheets used in the model provide a compact representation, thereby facilitating review and presentation of the information content.
Processing technique for scientific data telemetered to Earth from Mariner IV Mars probe
A methodology to eliminate model reflection and system vibration effects from post processed particle image velocimetry data is presented. Reflection and vibration lead to loss of data, and biased velocity calculations in PIV processing. A series of algorithms were developed to alleviate these problems. Reflections emanating from the model surface caused by the laser light sheet are removed from the PIV images by subtracting an image in which only the reflections are visible from all of the images within a data acquisition set. The result is a set of PIV images where only the seeded particles are apparent. Fiduciary marks painted on the surface of the test model were used as reference points in the images. By locating the centroids of these marks it was possible to shift all of the images to a common reference frame. This image alignment procedure as well as the subtraction of model reflection are performed in a first algorithm. Once the images have been shifted, they are compared with a background image that was recorded under no flow conditions. The second and third algorithms find the coordinates of fiduciary marks in the acquisition set images and the background image and calculate the displacement between these images. The final algorithm shifts all of the images so that fiduciary mark centroids lie in the same location as the background image centroids. This methodology effectively eliminated the effects of vibration so that unbiased data could be used for PIV processing. The PIV data used for this work was generated at the NASA Langley Research Center Quiet Flow Facility. The experiment entailed flow visualization near the flap side edge region of an airfoil model. Commercial PIV software was used for data acquisition and processing. In this paper, the experiment and the PIV acquisition of the data are described. The methodology used to develop the algorithms for reflection and system vibration removal is stated, and the implementation, testing and validation of these algorithms are presented.
NERVA transfer functions evaluation by computer data processing, using Fourier algorithm
Engineering specifications of signature data processing system for automatic extraction of spectral information from multispectral band scanners - Vol. 3
Some of the data handling considerations that led to the formulation of the data processing requirements for the ERTS system are discussed. The significant parameters that influence these requirements are: (1) payload characteristics, (2) spacecraft characteristics such as orbit, attitude and attitude rates, (3) payload coverage, and (4) product types and quantities. Items 3 and 4 have had the most significant influence on the generation of the requirements.
Beginning with a survey of the state-of-the-art of processing remotely sensed data in early 1975, significant developments between that time and the present are chronicled, and technologies for early 1979 are projected. Current technical issues discussed include: training selection and labeling; classification and mensuration; use of satellite indicators to supplement predictions; small scale field structures; physical factors; ancillary data; geometric quality; and the cost of processing.
The Miniaturized Laser Heterodyne Radiometer (mini-LHR) is a passive ground instrument that observes the mole fraction of carbon dioxide (CO) and methane (CH)in the atmospheric column by measuring their absorption of sunlight at 1.6 microns. A laser heterodyne radiometer is similar in design to the super heterodyne radio receiver that is well known by ham radio enthusiasts. While not previously a commercial technique, laser heterodyne radiometers have a history of measuring atmospheric trace gases that started in the 1960s. With the commercial availability of inexpensive, low-power, thumbnail-sized lasers developed for the telecommunications industry, it was possible to miniaturize this technique and ultimately commercialize it. The mini-LHR has been under development at NASA GSFC since 2009. During that time, in addition to signicant technical improvements, processing has also evolved and been streamlined. Here we present details of the processing approach for raw mini-LHR data to produce 30- and 60-minute data products of CH and CO column mole fractions. Processing occurs in two general stages: a python-based pre-processing of raw data, followed by ingestion into a Planetary Spectrum Generator (PSG) retrieval algorithm. Raw data processing involves removal of outliers, correcting for changes in air mass throughout the day, averaging scans, and ultimately converting averaged scans into transmittance vs. wavelength. The PSG retrieval simulates a spectra for the time/day/location of the scan with meteorological inputs from Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) data set and then perturbs the concentrations of CO and CH to obtain a t based on an iterative least-squares curve fitting procedure.
Digital image processing, image recorders, high-density digital data recorders, and data system element processing for use in an Earth Resources Survey image data processing system are studied. Loading to various ERS systems is also estimated by simulation.
The impact of a conical scan versus a linear scan multispectral scanner (MSS) instrument on a small local-user data processing facility was studied. User data requirements were examined to determine the unique system rquirements for a low cost ground system (LCGS) compatible with the Earth Observatory Satellite (EOS) system. Candidate concepts were defined for the LCGS and preliminary designs were developed for selected concepts. The impact of a conical scan MSS versus a linear scan MSS was evaluated for the selected concepts. It was concluded that there are valid user requirements for the LCGS and, as a result of these requirements, the impact of the conical scanner is minimal, although some new hardware development for the LCGS is necessary to handle conical scan data.