An anthropogenic sound suppression method for acoustic diversity index

Aiming at the problem that the Acoustic Diversity Index (ADI) obtained from the marginal area of the nature reserve is easily affected by the noise of human activities outside the area, the advantages of the Differential Microphone Array (DMA) that has low processing complexity and can rapidly form full-band spatial notch are used. Firstly, two sets of backto-back dual-delay DMAs with coprime delay factors are applied to adaptively filter out the anthropogenic noise from a fixed direction. Then, the two sets of spatial filtering outputs are used to suppress the grating lobe effect of the highfrequency pattern of DMAs based on the notch interleaving features in the two-dimensional space consisting of angle and frequency. Finally, the 0-1 detection component of the biotic signal is reconstructed at all time-frequency bins by taking the larger one between the two values, so as to restore the ideal ADI in the whole space without anthropogenic noise. It will provide a feasible idea for robust and accurate monitoring and evaluation of biological acoustic diversity in areas close to human activities.