IEC 60268-16:2011 specifies objective methods for rating the transmission quality of speech with respect to intelligibility. It provides a comprehensive manual for all types of users of the STI method in the fields of audio, communications and acoustics. Three methods are presented, which are closely related and are referred to as STI, STIPA, and STITEL. The first two methods are intended for rating speech transmission performance with or without sound systems. The STITEL method has more restricted uses.

可依据 ISO 3382(室内声学)、ISO 18233(分析方法)和 IEC 60268-16(语音清晰度)相关标准,在现场或实验室测量室内声学参数

STI 概念基于完全根据经验的发现,语音信号的波动带有涉及语音清晰度的相关的信息。语音的波动是由于句子、单词和音素(这些都是语音的基本要素)的声学间隔而产生的。这种波动的专**词是调制,可以通过产生调制频谱的调制频率 fm的函数来进行量化。对于清晰的语音,典型的调制频率从 0.5 Hz延伸到 16 Hz,调制在大约 3 Hz处。
调制频谱通过传输通道的任何降低通常被认为是会导致语音清晰度的降低。调制频谱的这种降低对应于在一个或多个调制频率处的调制深度的降低,并且作为每个倍频带在语音频谱范围上的调制传输数值来计算。

-/gjieib/-
http://nytesting.b2b168.com