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Application of Fourier transforms for microwave radiometric inversionsExisting microwave radiometer technology now provides a suitable method for remote determination of the ocean surface's absolute brightness temperature. To extract the brightness temperature of the water from the antenna temperature, an unstable Fredholm integral equation of the first kind is solved. Fourier transform techniques are used to invert the integral after it is placed into a cross correlation form. Application and verification of the methods to a two-dimensional modeling of a laboratory wave tank system are included. The instability of the ill-posed Fredholm equation is examined and a restoration procedure is included which smooths the resulting oscillations. With the recent availability and advances of fast Fourier transform (FFT) techniques, the method presented becomes very attractive in the evaluation of large quantities of data.
Document ID
19760032918
Document Type
Reprint (Version printed in journal)
Authors
Holmes, J. J. (West Virginia Univ. Morgantown, VA, United States)
Balanis, C. A. (West Virginia Univ. Morgantown, VA, United States)
Truman, W. M. (West Virginia University Morgantown, W. Va., United States)
Date Acquired
August 8, 2013
Publication Date
November 1, 1975
Publication Information
Publication: IEEE Transactions on Antennas and Propagation
Volume: AP-23
Subject Category
INSTRUMENTATION AND PHOTOGRAPHY
Funding Number(s)
CONTRACT_GRANT: NGR-49-001-056
Distribution Limits
Public
Copyright
Other