A Robust Feature Extraction Algorithm for the Classification of Acoustic Targets in Wild Environments

Abstract

The acoustic recognition technology of unattended ground sensor systems applied in wild environments is faced with the challenge of complicated and strong acoustic noise, especially wind noise. Moreover, the commonly used Mel-frequency cepstral coefficients (MFCCs) are sensitive to noise interference. To resolve the problem, a robust feature extraction method, called harmonic Mel-frequency cepstral coefficients (HMFCCs), is proposed for acoustic target classification. By combining an acoustic signal's harmonic model with the MFCC method, the HMFCC has the ability to emphasize the signals emitted by the principal acoustic components of the target. In the experiment conducted for this study, three data sets are sampled under the same conditions, except for wind power levels. Then the classifier, which is trained by one of the three data sets, is used to recognize the others data sets. According to the experimental results, the HMFCC-based classification accuracies of the three data sets are higher than those of other state-of-the-art methods, indicating that HMFCC is a kind of noise-insensitive feature.