Examples of usage of nearfield acoustic holography methods for far field estimations: Part 1. CW signals
This work addresses acoustic measurement challenges for researchers or engineers, but it appears incremental as it builds on existing methods with specific optimizations.
The paper tackles the problem of estimating far-field acoustic signals using nearfield acoustic holography methods, achieving a significant reduction in measurement complexity by enabling the use of a linear array instead of a planar array.
The paper is devoted to the usage of nearfield acoustic holography methods for estimating far field of the object. An experiment was carried out in anechoic chamber. First, acoustic filed was recorded in a plane that was close to source. This signals records were used to reconstruct the far field by computation routines. Second, the signal in the far field is measured and the results are compared. Several methods are tested and research on possible reduction of the microphone array size is carried out. The most significant reduction of the measurement facility complexity is usage a linear array in stead of the planar array that is made possible due to introduced computation routines