Envisat ASAR AP Precision L1 [ASA_APP_1P]

The product contains two CO-registered images corresponding to one of the three polarisation combination submodes (HH and VV, HH and HV, VV and VH). This is a stand-alone multi-look, ground range, narrow swath digital image generated using the SPECAN algorithm and the most up to date auxiliary information available at the time of processing.

Engineering corrections and relative calibration (antenna elevation gain, range spreading loss) are applied to compensate for well-understood sources of system variability. Generation of this product uses a technique to allow half the looks of an image to be acquired in horizontal polarisation and the other half in vertical polarisation and processed to 30-m resolution (with the exception of IS1). Absolute calibration parameters are available depending on external calibration activities and are provided in the product annotations.