Research On High-resolution And Fast DAMAS Technology

The deconvolution approach for the mapping of acoustic sources(DAMAS)is a high-resolution acoustic source identification and location technique based on the cross-spectral mapping beamforming technique.The spatial resolution of DAMAS is significantly higher than conventional beamforming technology,so DAMAS has a wide range of applications in the noise control and fault diagnosis and is worth to study.This paper first reviews the development of DAMAS algorithms,the research status and development trend of the algorithms are also analyzed.Analysis found that the existing algorithm in the performance adavantages and scope of application isd different.To give a reasonable guidance for choosing the suitable deconvolution approach for the mapping of acoustic sources algorithm in the engineering application and giving full play to the performance advantages of each algorithms,the spatial resolution and computational efficiency of these algorithms are studied under different frequencies,measuring distances,the position of measuring point and number of focal points by numerical simulation.The simulation results show that the sparsity reconstruction DAMAS algorithms has the highest spatial resolution,but the computational efficiency of the sparsity reconstruction DAMAS algorithms is relatively low since it needs to calculate the complete point spread function matrix.Fourier transform based on DAMAS algorithms has a higher computational efficiency.But Fourier transform based on DAMAS algorithms are solved to obtain the least square solution and the results is affected with the wrap-around error introduced by Fourier transform,the spatial resolution is lower than the sparsity reconstruction DAMAS algorithms.According to the simulation results,a reasonable guidance for choosing the proper algorithms in practical engineering applications is given.It can be seen from the conclusions that the existing DAMAS algorithms still have the limitations of spatial resolution or computational efficiency.In order to improve the spatial resolution and computational efficiency of the DAMAS algorithm,a novel high-resolution fast DAMAS is proposed.The performance of proposed method and the existing DAMAS method are compared by numerical simulations.The correctness of the simulation results is also verified in the anechoic chamber by the experiment with two white noise sources.Finally,the proposed method is used to identify the location of the main noise source of a data acquisition case,which validates the effectiveness and practicability of the proposed method.Simulation and experimental results show that the high resolution fast DAMAS algorithms proposed in this paper not only has the high spatial resolution of the similar sparse reconstructed DAMAS,but also has a much higher computational efficiency than the existing DAMAS.So it is very suitable for practical applications.