A panel speaker array with omnidirectional radiation pattern is presented in this paper. Array signal-processing techniques are utilized to manipulate the sound beam electronically such that wide-angle radiation can be maintained over a large frequency range. In order to achieve this purpose without sacrificing the array efficiency, the genetic algorithm (GA) is employed in the design stage to calculate the optimal array coefficients. The GA proved to be an effective technique in searching for the array coefficients that maximize the efficiency with desired flatness of radiation pattern. In addition, a modified design is also proposed to further enhance the efficiency in the low frequency range. The resulting designs are implemented on a digital signal processor platform and experimentally verified by using a small 5×1 panel speaker array and a large 3×3 panel speaker array.

Issue Section:
Technical Papers
Keywords:
loudspeakers, genetic algorithms, acoustic radiators, array signal processing, acoustic signal processing
Topics:
Design, Genetic algorithms, Signal processing, Optimization
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