Matsumoto Mitsuharu, Hashimoto Shuji
Department of Applied Physics, Waseda University, 55N-4F-10A, 3-4-1 Okubo, Tokyo 169-8555 Japan.
J Acoust Soc Am. 2008 Apr;123(4):2117-25. doi: 10.1121/1.2871764.
This paper describes an acoustical array combining microphones and piezoelectric devices. Conventional microphone arrays have been widely utilized to realize noise reduction, sound separation and direction of arrival estimation system. However, when a conventional microphone array is mounted on a real system, such as a machine, vehicle or robot, the microphones are set extremely close to the system's actual body. In such cases, the noise from the system itself, such as motors, gears, and engines, namely internal noise, often becomes a troublesome problem. It is difficult to reduce internal noise utilizing a conventional microphone array because internal noise sources are extremely close to the microphones. As internal noise is not always stationary, statistically independent or sparse, most useful blind source separation approaches, such as independent component analysis and the sparseness approach, cannot be employed. Our aim is to reduce internal noise utilizing microphones and piezoelectric devices attached to the internal noise source. In this paper, a general description of the acoustical array is formulated and the characteristic features of microphones and piezoelectric devices in an acoustical array are given. An acoustical array combining microphones and piezoelectric devices is also described with some experimental results.
本文描述了一种结合麦克风和压电装置的声学阵列。传统的麦克风阵列已被广泛用于实现降噪、声音分离和到达方向估计系统。然而，当将传统麦克风阵列安装在实际系统上，如机器、车辆或机器人时，麦克风被设置得极其靠近系统的实际主体。在这种情况下，来自系统本身的噪声，如电机、齿轮和发动机产生的噪声，即内部噪声，常常成为一个棘手的问题。利用传统麦克风阵列很难降低内部噪声，因为内部噪声源离麦克风非常近。由于内部噪声并非总是平稳的、统计独立的或稀疏的，大多数有用的盲源分离方法，如独立分量分析和稀疏方法，都无法采用。我们的目标是利用附着在内部噪声源上的麦克风和压电装置来降低内部噪声。本文对声学阵列进行了一般性描述，并给出了声学阵列中麦克风和压电装置的特征。还描述了一种结合麦克风和压电装置的声学阵列，并给出了一些实验结果。
