Full Spatial Response
of SeaWinds Measurements
Imaging applications of SeaWinds on QuikSCAT and ADEOS II are
facilitated by applying reconstruction and resolution enhancement
algorithms to produce high resolution images of the surface normalized
radar cross section (sigma-0). Such algorithms require a description
of the spatial response functions of the measurements. The pencil-beam
design of Seawinds, coupled with the onboard processing, results
in a spatial response function with varies significantly between
measurements and is a function of orbit and antenna position.
contour plot of the complete spatial response for one slice.
Computing the spatial response function is complicated and requires
significant computation. It requires evaluating the parameters of
the radar equation as well as detailed knowledge of the orbit geometry
and instrument processing. For this reason we have developed a method
of pre-computing, tabularizing and interpolating the complete response function
as a function of orbit and antenna position and other necessary parameters.
For more details see the paper, M.P. Owen, K.M. Stuart, and
D.G. Long, "Ultra-High-Resolution Near-Coastal Wind Retrieval
for QuikSCAT ",
in "Coastal Ocean Remote Sensing", Proceedings
of SPIE Vol. 6680, 26-27 Aug 2007. (PDF
Separate tables are available for horizontal and vertically
polarized slice measurements. Hpol tables
are available here while Vpol
tables are available here.
Software components to interpolate and reconstruct the complete slice
spatial response are available for Matlab and C. Additionally
example programs illustrate how to use the packages provided.
QuikSCAT data files must be acquired separately.
Software is available here.
Note that the software and tables are copyright Brigham Young University,
2007. The software may be used for non-commerical purposes provided
that proper acknowledgements are made and the paper mentioned above