Two-frequency /Delta k/ microwave scatterometer measurements of ocean wave spectra from an aircraftA technique for remotely sensing the large-scale gravity wave spectrum on the ocean surface using a two frequency (Delta k) microwave scatterometer has been demonstrated from stationary platforms and proposed from moving platforms. This measurement takes advantage of Bragg type resonance matching between the electromagnetic wavelength at the difference frequency and the length of the large-scale surface waves. A prominent resonance appears in the cross product power spectral density (PSD) of the two backscattered signals. Ku-Band aircraft scatterometer measurements were conducted by NASA in the North Sea during the 1979 Maritime Remote Sensing (MARSEN) experiment. Typical examples of cross product PSD's computed from the MARSEN data are presented. They demonstrate strong resonances whose frequency and bandwidth agree with the surface characteristics and the theory. Directional modulation spectra of the surface reflectivity are compared to the gravity wave spectrum derived from surface truth measurements.
Document ID
19820063958
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Johnson, J. W. (NASA Langley Research Center Hampton, VA, United States)
Jones, W. L. (NASA Langley Research Center Hampton, VA, United States)
Weissman, D. E. (Hofstra University Hempstead, N.Y., United States)