摘要
This paper describes in detail an acoustical array structure with four elements that have cosine directivity function over a certain frequency range. The acoustical axis directions of these elements are orthogonal to each other, so their beams cover all bearing angles within 360° . By use of the amplitude bearing method, it is easy to detect the bearing of incident acoustic signal. A special sound reflection foam rubber is designed as a back baffle of the array. It has been shown, in practice, that the constant beam-width has been obtained for a multiple frequency band of the ratio of 8:1. The paper also gives a mathematical model for the array structure. The theoretical values are consistent with the measured results.
This paper describes in detail an acoustical array structure with four elements that have cosine directivity function over a certain frequency range. The acoustical axis directions of these elements are orthogonal to each other, so their beams cover all bearing angles within 360° . By use of the amplitude bearing method, it is easy to detect the bearing of incident acoustic signal. A special sound reflection foam rubber is designed as a back baffle of the array. It has been shown, in practice, that the constant beam-width has been obtained for a multiple frequency band of the ratio of 8:1. The paper also gives a mathematical model for the array structure. The theoretical values are consistent with the measured results.
