Discriminant analysis of signal of X4 unmanned aerial vehicle

The aim of the present study was analysis of the acoustic signal of unmanned aerial vehicle equipped with 4 rotating propellers using time-frequency analysis and discriminant function analysis. The analysis was performed to investigate the characteristic frequencies of the unmanned aerial vehicle, and the differences between signals of the unmanned aerial vehicle at different altitudes using Mel-frequency cepstral coefficients and discriminant function analysis. The signals were acquired when the unmanned aerial vehicle was hovering at 50 m, 100 m, 150 m, and 200 m. Results showed the characteristic frequencies of the unmanned aerial vehicle up to 1 kHz and at 4 kHz. Discriminant function analysis based on Mel-frequency cepstral coefficients showed significant main effects between signals of the unmanned aerial vehicle hovering at different altitudes but no significant differences between signals of the unmanned aerial vehicle hovering at the same altitude. The analysis may prove important in applications for detection of unmanned aerial vehicles.