Wideband holography based spherical equivalent source method with rigid spherical arrays. (October 2018)

• Record Type: Journal Article
• Authors: Ping, Guoli; Chu, Zhigang; Yang, Yang; Xu, Zhongming
• Is Part Of: Mechanical systems and signal processing. Volume 111(2018)
• Page Start: 303
• Page End: 313
• Publication Date: 2018-10
• Subjects: Spherical equivalent source method -- Near-field acoustical holography -- Rigid spherical arrays -- Three-dimensional acoustic source identification -- Reconstruction performance; Structural dynamics -- Periodicals; Vibration -- Periodicals; Constructions -- Dynamique -- Périodiques; Vibration -- Périodiques; Structural dynamics; Vibration; Periodicals; 621
• DOI: 10.1016/j.ymssp.2018.04.006
• Languages: English
• ISSNs: 0888-3270

Abstract

Highlights: A new WBH-based S-ESM is proposed by a combination of S-ESM and WBH solution. Its good high-frequency performance of reconstruction and identification is examined. The adaptability to large hologram distances is explored. It extends the upper frequency limit and enlarges the measurement distance of S-ESM. Abstract: Spherical equivalent source method (S-ESM) with rigid spherical arrays is able to achieve good sound field reconstruction and acoustic source identification in three-dimensional free-field spaces. However, the S-ESM solved by the standard Tikhonov regularization is restricted to the low-frequency reconstruction and source identification at small measurement distances. To make S-ESM achieve good reconstruction and source identification at high frequencies and large hologram distances, this study proposes a sparsity-promoting approach denoted as wideband holography based S-ESM (WBH-based S-ESM), which applies a steepest descent method to iteratively solve S-ESM. Firstly, the framework of WBH-based S-ESM is established. Subsequently, to examine its validity, the performance of reconstruction and source identification is compared with Tikhonov regularization. Finally, a focus is concerned with the adaptability to large hologram distances. Several meaningful results have emerged from simulations and experiments: (1) WBH-based S-ESM can make good sound field reconstruction and acoustic source identification at medium-high frequencies. It extends the upper frequency limit of S-ESM. (2) The maximum hologram distance of WBH-based S-ESM at high frequencies is greater than that of Tikhonov regularization. It enlarges the measurement distance of S-ESM. This study will demonstrate the potential of WBH-based S-ESM as a useful tool for reconstruction and source identification.