Using Hrtf 3d Sound Field Alarm System

Virtual Reality technology has been developed in a variety of fields for the past few years thanks to the development of computer science and information technology.As an important compensation of vision, auditory information can play a good role in many applications. For example, in pilot training people get most of information by watching radar and television aid, but if they can"hear"the target movement then they can make good use of their ears rather than depending only on their eyes.Using just two receivers (ears), humans are able to localize sound with amazing precision. As a matter of fact, the wavelength of audible sound (2cm-20m) is comparable to the dimensions of the human body, and the external ear is for high audible frequencies. As a result, human body and the external ear essentially form a specially-shaped"antenna"that causes a direction-of-arrival dependent"filtering"of the sound reaching the eardrums. The effect of this scattering can be described by a frequency response function called the head-related transfer function (HRTF).This paper tries to build a virtual 3-dimension sound alarm system using HRTF for potential use in cockpit for pilots. The problem is that HRTF data is individualized or personal, so when non-individual HRTF is used, sound localization may be worse, especially front-back sound localization. A raw database of HRTF released by U.C. Davis CIPIC Interface Laboratory is used for research on improvement of front-back sound location characteristics of HRTF database. Experiments are carried out in MATLAB and a new algorithm for effect enhancement based on SRS is proposed.This paper designed the 3D sound alarm system which includes three subsystems, and finally built the system in VC++. The system is a real-time audio processing system and can provide three different alarm modes.