关键词: 双谱, 特征提取, 分类, 水下目标

Abstract: According to the characteristics of human eyes’ classifying bispectra，two extraction schemes for bispectra magnitudes matrix elements are proposed in a triangle area defined by bispectrum symmetry.They are extraction scheme along the direction parallel to the vice diagonal and that along the direction of column vector，respectively.And 4 feature vectors are obtained by simple summation operation or maximum operation to the extracted elements.By using One-against-One（OAO） method of multi-classification of Support Vector Machine（SVM），it is validated that very high mean classification accuracy can be obtained by summation operation to the first extraction scheme.The classification accuracy of the feature vector obtained by the above method are 100% for the radiated noise of underwater targets in three types A，B and C.And the mean classification accuracy for the other feature vectors proposed by this paper are steadily above 95%.

Key words: bispectrum, feature extraction, classification, underwater targets