Development of sound source for remote conference and remote education using focused parametric array sound field

研究了一种用于远程会议和远程教育的音响系统，该系统使用了参数阵列效应的高方向性声场。传统的远程会议系统使用普通的扬声器进行会议，使用传统的耳机进行教学，存在会议信息泄露、噪声污染、声音反馈等问题。我们试图利用参数阵效应产生的高方向性声场来解决这些问题。首先，制作了一个聚焦和集成的参数阵声源，并考察了其可调整性。结果表明，声音属性对语音声音是自适应的。然后，将音响系统与屏幕相结合，实现了远程会议系统，并在实际的远程会议和远程教育领域进行了测试。然而，我们也发现了一些问题。一个问题是，该系统不适应音乐来源。另一个问题是由于监听器的头部散射了接收到的声音，所以对周围区域产生了额外的声压。总之，该系统适用于远程会议和教育，在正常声源的情况下，如人声和相对较低的频率声音。

A sound system for remote conferences and remote education using a high directional sound field that uses an effect of parametric array was examined. The conventional remote systems through the Internet use a normal speaker for a conference and conventional head phones for education, and there are many problems such as leak of information of conference, noise pollution and acoustic feedback. We tried to delete these problems by use of high directional sound field, made by parametric array effect.First a focused and integrated parametric array sound source was made and adjustability for the purpose was examined. As a result, the sound properties were shown to be adaptive to voice sound. And then, the sound system was combined with a screen to realize a remote conference system.This system was evaluated at the real field of remote conference and remote education. However, We found out some problems. One problem is that the system is not adaptive to music source. And another problem is an additional sound pressure to surrounding area because the head of the listner scatters the received sound.In conclusion, The system is useful for remote conferences and education in the case of a normal sound source such as human voice and comparably low frequency sound.