Response (Xshape) code
Sample programs which compute the spatial response functions for
egg and slice measurements are available in fortran and C. The code
requires QuikSCAT or SeaWinds L1B data and includes simple HDF readers
for this product type. The general algorithm and tables are described
in the paper The data tables and code are described in the paper
I.S. Ashcraft and D.G. Long, "The spatial response function
of SeaWinds backscatter measurements", in "Earth Observations
Systems VIII", W.L. Barnes, ed., Proceedings of SPIE Vol.
5151, 3-6 Aug 2003. (PDF file)
Inputs to the computation are the shape tables, the instrument
resolution mode, the orbit time step, the antenna azimuth angle,
the boresite location on the surface, and (for the slice case) the
slice number. The egg response is approximated as a two-dimensional
polynominal in latitude and longitude while an 8 point contour line
corresponding to the 6 dB response is returned for slices.
This code and tables are made available as a public service. While
the code has been tested on a SUN, HPUX, and linux platforms, no
claim is made for the correctness or suitability of the code or
tables for any purpose. Any use of this code is made at the user's
own risk. Source code may be freely copied and modified as long
as (1) original authorship is acknowledged, and (2) code is not
distributed for profit without prior authorization from David G.
Long at Brigham Young University, Please sent a copy of any papers
resulting from using this code or data tables to Prof. David Long,
459 Clyde Building, BYU, Provo, UT 84602. Source code is copyright
2003 Brigham Young University, Provo, UT.
Slice Code (C)
Slice Code (fortran)
(Note some Matlab utilities and graphic images are included in these directories.)