Distribution and Statistical Characteristics of a Small UAV Audio Signal

This chapter discusses the sound radiation of an Unmanned Aerial Vehicle (UAV) on the example of a small UAV Phantom 4. Recently, UAV are widely applied to many functions of the modern world. The spectra of the audio signal are calculated, the harmonic components of the spectrum and the rotation frequency of the engine rotor are determined. Application of a Windowed Fourier Transform to this audio signal is investigated. Obtained results show that audio signal is non-stationary and second, fourth, and sixth harmonics have powerful values, but their values are not constant. The histograms of the audio signal and their approximation by various distribution laws are obtained. The law of distribution of instantaneous values of UAV audio signal is evaluated. On the base of Kolmogorov’s normability criterion, it is obtained that the Student’s distribution is the most suitable law of distribution for these realizations.