Calibration Change (Data Acquired Jun 14 2011 - Aug 1 2012)
The UAVSAR processing team has reprocessed some UAVSAR data due to a change in calibration for data acquired between flights 11035 and 12067. The re-calibration only affects data from these flights first processed with a processor version prior to 1.26.4. Version 1 (which has a slight calibration error) and Version 2 (in which the calibration error has been corrected) are both archived.
It was discovered that after a hardware modification commencing with flight 11035, the calibration estimate for all channels changed by about -1 db. Version 2 processing compensates for this change in calibration. The brightness of all channels for version 2 is about 1 db brighter than in version 1. For more information about UAVSAR calibration, please download the UAVSAR calibration report.
If you want to convert version 1 data to version 2 calibration, multiply each pixel in the version 1 cross products image file (both MLC and GRD) by the complex quantities described below.
File amplitude phase(radians) HHHH 1.204 0.00 HVHV 1.304 0.00 VVVV 1.306 0.00 HHHV 1.253 0.0816 HHVV 1.2537 0.1294 HVVV 1.3048 0.0478