Wavelets and wavelet packets applied to detect and characterize transient alarm signals from termites

In this paper we show the possibility of using wavelets and wavelet packets to detect and characterize alarm signals produced by termites. A set of synthetics have been modelled by mixing the real acquired transients with computer generated noise processes. Identification has been performed by means of analyzing the impulse responses of three sensors undergoing natural excitations. De-noising exhibits good performance up to SNR = −30 dB, in the presence of white gaussian noise. The test can be extended to similar vibratory or acoustic signals resulting from impulse responses.