A loudspeaker arrangement and corresponding analysis method to obtain robust superdirective beam are proposed. The superdirectivity technique requires precise matching of the sound sources modeled to calculate excitation pattern and those used for the loudspeaker array. To resolve the robustness issue arising from the modeling mismatch error, we show that the overall sensitivity to the model-mismatch error can be reduced by rearranging loudspeaker positions. Specifically, a beam pattern obtained by a conventional optimization technique is represented as a product of robust delay-and-sum and error-sensitive differential patterns. The excitation pattern driving loudspeaker array is then reformulated such that the error-sensitive pattern is only applied to the outermost loudspeaker elements, and the array design that fits to the new excitation pattern is discussed.
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