三维运动声音在机载告警系统中的应用

【作者】 杨小冬；

【导师】 李晓峰；

【作者基本信息】 电子科技大学 ， 通信与信息系统， 2006， 硕士

【摘要】 本文主要研究了三维运动声音在机载告警系统中应用的相关问题。三维声音告警技术具有简单、信息量大的特点,可以充分利用听觉及时地为飞行员提供大量具有空间感的告警信息,从而提高飞行安全。用声音表现三维运动是以运动学、声学、人类生理声学、心理声学等研究成果为理论基础,以数字信号分析、处理、合成为实现手段,以耳机或扬声器为输出工具,实时合成能够反映等同三维真实空间中运动物体特性的声音信号。对人类生理声学和心理声学的了解是研究三维声音技术的基础。因此,介绍了人耳听觉模型和听觉效应,分析了哈斯效应、耳廓效应、反射与混响等因素对听觉的影响。由于定位是三维声音技术的重点,所以,介绍了传统定位理论,并在分析其不足后引入了头部关联传递函数(Head-Related Transfer Function,HRTF)的定位理论。详细介绍了HRTF的获取方法,分析了HRTF的基本特性,从而进一步研究定位原理。不过,HRTF还是存在不足:数据不准确、不全面,无法提供足够的距离信息等。三维运动声音的特性主要包括:距离、速度、方位。因此,在研究这三种特性的仿真原理的基础上提出相应的仿真算法。为了得到真实感的声音引入混响的概念,通过分析混响原理提出混响生成方法。加入混响的声音解决了距离判断的模糊问题,减小了“头中定位”效应,使处理后的声音更自然。经过实验验证了各仿真算法的可行性,在分析存在的问题之后提出了改进后的系统仿真方案。更多还原

【Abstract】 The application of 3D moving sound in the warning system in fighter is studied in this dissertation. 3D sound warning technology is simple and can supply a lot of information, so the pilot can obtain enough warning information with spatial sense to improve the safety of flying.Representing 3D movement by sound is on the basis of kinematics, acoustics, physiological acoustics, psychological acoustics and etc. By the means of analysis, processing and synthesis of digital signal, 3D sound is achieved and output by earphone or speaker. The goal of research is reflecting the moving characteristics of the object in the real world by processed sound in real time.The knowledge of physiological acoustics and psychological acoustics is the basis of the research of 3D sound technology. Therefore, the model of human ear and the hearing effect are introduced, and the influence of Hass effect, pinnae effect, reflection and reverberation to the hearing is analyzed too. Since localization is the emphasis of 3D sound technology, traditional localization theory is discussed, after analyzing its shortage Head-Related Transfer Function (HRTF) localization theory is presented. The acquirement and characteristics of HRTF is discussed in detail, thereby, the localization theory is studied further. However, HRTF has shortage too, for instance, it is not accurate and full-scale, and it can not supply sufficient information of distance.The characteristics of 3D moving sound are distance, velocity and localization. Hence, on the bases of investigating the simulation principles, the corresponding simulation algorithms are proposed. For the sake of acquiring sound with third dimension, the concept of reverberation is presented. By analyzing the principle the method of creating reverberation is put forward. The faintness of judging distance is resolved, and Inside-the-Head Location effect is eased by adding reverberation. The feasibility of the simulation algorithms is validated through the experiment, and the improved simulation scheme is brought forward after analyzing existent problems.更多还原