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Newton, R. W.

Publications and source records attributed to Newton, R. W..

22 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

Improvements and modifications to the NASA microwave signature acquisition system

A user oriented description of the modified and upgraded Microwave Signature Acquisition System is provided. The present configuration of the sensor system and its operating characteristics are documented and a step-by-step operating procedure provides instruction for mounting the antenna truss assembly, readying the system for data acquisition, and for controlling the system during the data collection sequence. The resulting data products are also identified.

Jean, B. R.↗
NASA NTRS1977

Microwave remote sensing and its application to soil moisture detection

The author has identified the following significant results. Experimental measurements were utilized to demonstrate a procedure for estimating soil moisture, using a passive microwave sensor. The investigation showed that 1.4 GHz and 10.6 GHz can be used to estimate the average soil moisture within two depths; however, it appeared that a frequency less than 10.6 GHz would be preferable for the surface measurement. Average soil moisture within two depths would provide information on the slope of the soil moisture gradient near the surface. Measurements showed that a uniform surface roughness similar to flat tilled fields reduced the sensitivity of the microwave emission to soil moisture changes. Assuming that the surface roughness was known, the approximate soil moisture estimation accuracy at 1.4 GHz calculated for a 25% average soil moisture and an 80% degree of confidence, was +3% and -6% for a smooth bare surface, +4% and -5% for a medium rough surface, and +5.5% and -6% for a rough surface.

Newton, R. W.↗
NASA NTRS1972

Experimental measurements of 2.25-cm backscatter from sea surfaces.

Airborne 2.25-cm wavelength radar backscatter measurements of low-wind-speed sea conditions were obtained off the coast of Texas in January 1971. These data are compared with unpublished NASA 2.25-cm backscatter measurements recorded over the Atlantic in 1970. The two data sets were in general agreement and supported results previously reported by other authors which showed the absence of a saturation effect at this wavelength. Analyses of these data using computerized clustering techniques indicated that a wind speed measurement accuracy of 5-7 knots is an operational potential.

Newton, R. W.↗