ALOS PALSAR calibration and validation activities in Sweden

This paper gives an overview of activities and results from the Swedish part of the international calibration and validation efforts for ALOS PALSAR. Four large trihedral corner reflectors were deployed and the measured co-polar responses showed that the PALSAR system performed well and was stable over time. The cross-talk level was found to be lower than – 34.5 dB. Two different methods for estimation of Faraday rotation were tested and rotations of up to 3o were recorded. An evaluation of the possibilities to retrieve forest variables from PALSAR data has also been performed. The results indicate that clearcuts can be detected and under favorable conditions the stem volume estimation accuracy for a single image was 30%.