Auditory System Property About Speech Signal Process

With the rapid development of computer science, computer has great improvement in information processing and judgment, but computer information exchange with human has smaller progress, which makes the information bottleneck problem increasingly serious. Speech technology as one of the most important technologies in man-machine interface, experienced more than half a century of development, has made many major breakthroughs. In speech recognition, speaker recognition and speech synthesis fields, a lot of commercial products have entered the practical application stage, which brought great changes to the society. However, the existing technology in practical application environment still has some problems. So, the research of human auditory system properties is of extremely significance and value.The research on auditory system's robustness could be classified into two basic topics: bottom-up process and up-bottom process. Bottom-up process is the basic functional part of human auditory system, is used to analysis the physical character of sounds and classify them into different sound streams. But in up-bottom process, human auditory system reconstructs the sound scene based on consciousness, attention and experiences. The latter is the most remarkable difference between artificial system and human auditory system, is also the focus in auditory research field.In our research we studied these two processes' property of human auditory system from three different aspects. From the first experiment and analysis, we can find that in speaker recognition process, human auditory system takes the method similar with the information theory method, is also influenced by native language environment. In the second study, we find that in speaker recognition process, people use word-length or longer information, which is different with modern modals such as GMM. In third research, we found auditory system maybe takes not only the sound clues that existing theory explored, but also high level characteristic such as the kurtosis of spectral envelope, which could improve the system ability in some special conditions, e.g. whisper environment.