Engineering topics

Newton, J. M.

Publications and source records attributed to Newton, J. M..

4 records

NASA NTRS1982

Multispectral radiation detection of small changes in target emissivity

An investigation into the multispectral radiation detection of small changes in target emissivity has been performed by Georgia Tech. A series of ice detection measurements on the shuttle external tank (ET) were performed using an advanced instrumentation radiometer operating at 35/95 GHz. Actual shuttle ET ice detection measurements were run at NASA's National Space Technology Laboratory (NSTL) during cryogenic fueling operations prior to orbiter engine firing tests. Investigations revealed that ET icing caused an increase in surface brightness temperature and the test results further demonstrated the usefulness of millimeter wave radiometry for the detection of ice on the ET.

Gagliano, J. A.↗

NASA NTRS1981

Ice/frost detection using millimeter wave radiometry

A series of ice detection tests was performed on the shuttle external tank (ET) and on ET target samples using a 35/95 GHz instrumentation radiometer. Ice was formed using liquid nitrogen and water spray inside a test enclosure containing ET spray on foam insulation samples. During cryogenic fueling operations prior to the shuttle orbiter engine firing tests, ice was formed with freon and water over a one meter square section of the ET LOX tank. Data analysis was performed on the ice signatures, collected by the radiometer, using Georgia Tech computing facilities. Data analysis technique developed include: ice signature images of scanned ET target; pixel temperature contour plots; time correlation of target data with ice present versus no ice formation; and ice signature radiometric temperature statistical data, i.e., mean, variance, and standard deviation.

Gagliano, J. A.↗

NASA NTRS1980

Advanced millimeter wave imaging systems

Unique techniques are being utilized to develop self-contained imaging radiometers operating at single and multiple frequencies near 35, 95 and 183 GHz. These techniques include medium to large antennas for high spatial resolution, lowloss open structures for RF confinemnt and calibration, wide bandwidths for good sensitivity plus total automation of the unit operation and data collection. Applications include: detection of severe storms, imaging of motor vehicles, and the remote sensing of changes in material properties.

Schuchardt, J. M.↗

NASA NTRS1976

Computer analysis speeds corrugated horn design

A computer analysis program is developed for selecting the optimum flare angle and horn length of a corrugated horn design, the horn diameter, and the radiation pattern, before resorting to machining operations. The calculated antenna pattern is best suited to narrowband designs, and averaging of the E and H planes is recommended for wideband work. The program language used is BASIC. Some design examples are provided with representative data, printouts, and a rundown of the equations programmed.

Loefer, G. R.↗