In the first phase, we carried out the dual classification, determine whether a syntactic component is a semantic role, then do multi-classification to assign a specific semantic role.

Speckle in SAR images will disturb classification accuracy. Vector filter of speckle is used to dual-frequency images before classification.

On the basis of subspace classifier the concept of subspace is developed and a new concept called dual subspace and corresponding algorithm of classification are presented in this paper.