A-Weighting for Acoustic Radiation Shaping of a Vibrating Plate.

The investigated method enables precise shaping of acoustic radiation of a vibrating plate, i.e. it allows one to relocate or create resonances and anti-resonances for selected frequencies, simultaneously altering their acoustic radiation efficiency in a desired manner. The method can be very beneficial for plates used as noise barriers, both in passive and active applications. The acoustic radiation shaping method involves mounting several additional ribs and masses to the plate surface at locations followed from an optimization process (sensors and actuators can also be included, if active control is considered). The optimization process requires a model of the vibroacoustic system, a cost function corresponding to the considered objective, and an optimization algorithm. In this paper, an introduction of A-weighting to the cost functions, which reflects a human perception of the noise radiated by or transmitted through the plate, is investigated. It follows from the analysis of obtained results that the introduction of A-weighting can provide even 8 dBA better passive noise attenuation.