Estimation of the radiated sound power by linear array beamforming sound intensity scaling method

A sound intensity model was proposed which is constructed by concise linear array.The quantitatively calculation for radiated sound power can be implemented by the proposed model in the process of sound source identification by using beamforming technology.The sound intensity scaling factor in the linear array was deduced,and the conversion relation between the outcomes of the linear array beamforming and the radiated sound power was further established.For both linear array and planar array,it exists obvious error in estimation of radiated sound power by using sound intensity scaling method when sound sources are located far distance from the center of the array.By using theoretical derivation and simulation calculation,the variation of sound power estimated error for the single monopole point source at different positions was investigated with various frequency and amplitude.It can be concluded that the estimated deviation is only related to the position of the sound source rather than the intensity information of the sound source.The corresponding correction method was proposed accordingly.By comparison between the experimental results of semi-anechoic chamber and the measurement results of sound pressure method,it shows that the developed sound intensity scaling method based on the linear array can be used to calculate the radiated sound source power in medium and high frequency range.The estimated error is limited in 1.0 dB for single frequency sound source,and 1.8 dB for wideband sound source.