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Probabilities and statistics for backscatter estimates obtained by a scatterometer with applications to new scatterometer design dataThe values of the Normalized Radar Backscattering Cross Section (NRCS), sigma (o), obtained by a scatterometer are random variables whose variance is a known function of the expected value. The probability density function can be obtained from the normal distribution. Models for the expected value obtain it as a function of the properties of the waves on the ocean and the winds that generated the waves. Point estimates of the expected value were found from various statistics given the parameters that define the probability density function for each value. Random intervals were derived with a preassigned probability of containing that value. A statistical test to determine whether or not successive values of sigma (o) are truly independent was derived. The maximum likelihood estimates for wind speed and direction were found, given a model for backscatter as a function of the properties of the waves on the ocean. These estimates are biased as a result of the terms in the equation that involve natural logarithms, and calculations of the point estimates of the maximum likelihood values are used to show that the contributions of the logarithmic terms are negligible and that the terms can be omitted.
Document ID
19890013408
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Pierson, Willard J., Jr.
(City Coll. of the City Univ. of New York NY, United States)
Date Acquired
September 5, 2013
Publication Date
April 1, 1989
Publication Information
Publisher: NASA
Subject Category
Communications And Radar
Report/Patent Number
NASA-CR-4228
NAS 1.26:4228
Report Number: NASA-CR-4228
Report Number: NAS 1.26:4228
Accession Number
89N22779
Funding Number(s)
CONTRACT_GRANT: NAGW-690
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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