Performance Analysis And Optimization Of Sound Intensity Direction Vector Estimation Method For Four Element Orthogonal Array

Sound intensity is an important physical quantity which can describe the sound field.Its directional vector contains the azimuth information of sound source,which is widely used in underwater acoustic,indoor positioning and noise control.Using the sound intensity estimation method,the direction of the target sound source can be estimated through the microphone array.The quaternary orthogonal array studied in this paper is a typical three-dimensional array of microphones.Some typical sound intensity estimation methods have been proposed for this formation,such as Taylor approximation and three-point estimation.However,the performance analysis of these methods is carried out under ideal conditions,but in practice there is usually unavoidable microphone mismatch error,such as the microphone amplitude error,phase error.Therefore,it is of great importance to study the influence of mismatch error on the performance of typical sound intensity estimation methods.In response to this problem,this paper systematically analyzes the performance of the typical sound intensity estimation method in the presence of microphone mismatch error,and proposes a better performance of the sound intensity estimation method.The main work is summarized as follows:1.Compare the performance of Taylor approximation and three-point estimation under ideal conditions respectively.The simulation analysis shows that under the ideal conditions,the estimation error of the sound intensity direction which based on the Taylor approximation method is obviously lower than the three-point estimation method,and the advantage of the Taylor approximation method becomes more obvious with the increase of the wavenumber size product.2.The effects of microphone amplitude error and microphone phase error on the performance of typical sound intensity estimation methods are discussed respectively.The theoretical analysis shows that the Taylor approximation method is sensitive to the amplitude error of the microphone.In some cases,the amplitude error makes the estimation error of the direction vector of the sound intensity very large.The three-point estimation method has strong robustness to the amplitude error of the microphone.The estimation error of strong direction vector is small as a whole.The microphone phase error has the same effect on Taylor approximation and three-point estimation,both of which show that the azimuth estimation error is larger when the pitch angle is equal to 0~?/180~?.Through the simulation comparison,the correctness of the theoretical analysis is verified,and the most appropriate sound intensity estimation method in the presence of mismatch error is given.3.Propose an optimal linear sound pressure estimation method.We know that the sound intensity can be estimated by the joint estimation of sound pressure and vibration velocity.Therefore,based on the existing sound intensity estimation method,the sound pressure estimation method is considered to be optimized.By theoretical analysis,proposed a linear sound pressure estimation method which can make the sound intensity direction vector estimation error minimum.Simulation results prove that the proposed method of sound intensity estimation is superior to other typical methods of sound intensity estimation.The research results in this paper reveal some of the factors that affect the robust performance of the orthogonal array sound intensity estimation method and its laws.At the same time,the conclusions proposed in this paper provide a theoretical basis for the selection of sound intensity estimation methods in practical applications.