Duan Jun-Feng, Hong Jun. An Estimation Method of Faraday Rotation and Channel Imbalance of PolSAR Using Distributed Targets[J]. Journal of Electronics & Information Technology, 2008, 30(9): 2069-2072. doi: 10.3724/SP.J.1146.2007.00258
Citation:
Duan Jun-Feng, Hong Jun. An Estimation Method of Faraday Rotation and Channel Imbalance of PolSAR Using Distributed Targets[J]. Journal of Electronics & Information Technology, 2008, 30(9): 2069-2072. doi: 10.3724/SP.J.1146.2007.00258
Duan Jun-Feng, Hong Jun. An Estimation Method of Faraday Rotation and Channel Imbalance of PolSAR Using Distributed Targets[J]. Journal of Electronics & Information Technology, 2008, 30(9): 2069-2072. doi: 10.3724/SP.J.1146.2007.00258
Citation:
Duan Jun-Feng, Hong Jun. An Estimation Method of Faraday Rotation and Channel Imbalance of PolSAR Using Distributed Targets[J]. Journal of Electronics & Information Technology, 2008, 30(9): 2069-2072. doi: 10.3724/SP.J.1146.2007.00258
Besides the crosstalk and channel imbalance f of SAR system, calibration of the spaceborne Polarimetric SAR(PolSAR) also needs to consider the correction of Faraday rotation. This paper proposes a method for estimating Faraday rotation and channel imbalance which uses the statistical characteristics of distributed targets. The method does not need to know the scattering matrixes and only requires that the two different distributed targets satisfy reciprocity and reflection symmetry. In practical applications, it would be easy to find two different kinds of distributed targets(such as forests, farmland or pasture) which meet the requirements in one scene of the SAR image. Therefore the method proposed here has practical values. Simulation experiment with real PolSAR data is carried out to validate the method.
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