传声器系统指向性的实现主要有两种途径:一是通过特殊的声结构,二是通过传声器阵列。比较了一个带有抛物面形状反射面的传声器系统和与抛物面开口面积相同的圆形传声器阵列的差异。分别使用Kirchhoff-Helmholtz积分方程和阵列理论对这两种传声器系统的性能进行研究。数值模拟的结果表明,抛物面反射式传声器系统在高频时具有更高的灵敏度,其指向性通常也好于圆形传声器阵列。
Directivity requirement of sound picking system can be realized by using an acoustics structure or a microphone array. A non-array directional microphone with a parabolic reflector and a circular microphone array with equal cross section area are described and compared. The parabolic reflector microphone is studied based on the Kirchhoff-Helmhohz integral formula, and the circular microphone array is studied based on the array theory. Numerical simulation results show that the parabolic reflector microphone presents higher sensitivity at high frequencies, and it usually performs better directivity than that of circular microphone array.