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|Data Processing Revised Version Log|
AIRSAR Data Processor Version 6.38: 5/25/2003
Version 6.38 : 5/25/2003
AIRSAR Data Processor Version 6.37: 12/20/2002
Version 6.37 : 12/20/2002
For the (slant-range imagery) POLSAR mode data
sets the algorithm used in previous processor
For the POLSAR mode this version now uses the processing reference track peg-point (latitude, longitude and heading) to compute the ground location of the corner of the image. The coordinates generated in this way are more accurate than those generated using the previous method and are consistent with those generated for the TOPSAR data sets. See Figure 1.3 of the Data Format Document: http://airsar.jpl.nasa.gov/data/data_format.pdf for a depiction of the peg-point coordinates.
The parameter header (defined in
the Data Format Document) has been modified in the following way: Fields
14-17 have been updated with values using the new algorithm, and Fields
99 and 100 now report the correct along-track (S0) and cross-track (C0)
offsets for first sample of the image.
AIRSAR Data Processor Version 6.36: 06/05/2002
Version 6.36 : 06/05/2002
Problem Description :
CV Channel radiometric calibration anomaly in POLSAR mode
An IDL procedure was written (cvv_cal) to compensate for this antenna pattern anomaly. It reads in the C-band compressed Stokes matrix file, applies the correction curve (based on a reference data set) to the CHV and CVV channels, and writes the corrected data out to disk with the updated processor version number (6.36).
AIRSAR Data Processor Version 6.35: 02/15/2002
Version 6.35 : 02/15/2002
Image intensity error of the TOPSAR data in the new Phase Unwrapping program with a bug from the version 6.34. The bug was a ramp function applied on the image intensity data.
To remove the ramp function from the intensity data.
AIRSAR Data Processor Version 6.34: 02/04/2002
Version 6.34 : 02/04/2002
Problem Description :
Enhancing of Phase unwrapping function and a bug corrected is updated in this version 6.34 .
I) Phase unwrapping enhancement :
The new phase unwrapping program will bootstrap the next patch interferometric data for the phase unwrapping efficiency. Filtering the interferogram phase function is added as well.
II) Bug correction in the parameter header :
Three fields of the parameter header were corrupted due to the mis-allocation of the memory under certain circumstances. The corrupted annotations in the parameter header were Site_name, Image_title, and Frequency_ label.
This annotation anomaly did not affect the image quality at all.
The upgraded phase unwrapping with bootstrapping and filtering functions is on line .
The memory mapping of the header code was updated and corrected to correct Site_name, Image_title, and Frequency_ label in the parameter header .
AIRSAR Data Processor Version 6.33: 08/27/2001
Version 6.33 : 08/27/2001
The ENVI3.4/IDL software package from a third party can't read the length of Radiometric Correction Vectors beyond 19600 bytes(2450 samples*8).
So the Radiometric Correction Vectors will be truncated to 19600 bytes until ENVI fixes the bug. Many AIRSAR investigators use ENVI to analyze their data. Most TOPSAR data will not be affected since the ground projected images has fewer samples than the truncated correction vector.
For version 6.33, the integrated processor generates three extra files to contain the full size of each Radiometric Correction Vectors as cmxxxx_c.rad_vec , cmxxxx_l.rad_vec, and cmxxxx_p.rad_vec.
In the mean time, a README file is also generated as shown below.
RADIOMETRIC CORRECTION VECTORS ( ASCII format):
Column 1: for the HH channel
Column 2: for the HV channel
Column 3: for the VV channel
Each column of the above channel has a full size data as the same as range line size. The file names of each frequency are cmxxxx_c.rad_vec, cmxxxx_l. rad_vec , and cmxxxx_p.rad_vec.
Note: ENVI 3.4 can NOT read the size of Radiometric Correction Vectors of the AIRSAR Header beyond 19600 bytes. The maximum size of that is 24080. So, the Radiometric Correction Vectors of the AIRSAR Header contains only upto 19600 bytes for this version. ENVI 3.5/IDL 5.5 will fix this problems claimed by the company then the AIRSAR header length will go back to normal case.
AIRSAR Data Processor Version 6.32 : 06/25/2001
Version 6.32 : 06/25/2001
The Radiometric Correction Vector in the AIRSAR header had been generated with a constant shorter length (10240 sampels).
In version 6.32 the processor generates the full size of the radiometric correction vectors based on the number of range samples in each image file (up to 2560 samples instead of 1280 samples).
AIRSAR Data Processor Version 6.31 : 04/25/2001
Version 6.31 : 4/25/2001
There was an error in the calibration of the 40 MHz polarimetric L-band and P-band data which led to a mis-registration between C-band data and L/P-band datain both XTI1/XTI1P and POLSAR 40 MHz data .
Both POLSAR and XTI1 data are being re-processed and re-delivered to investigators for the affected data sets.________________________________________________________________________