Multi-objective Use Of Three-dimensional Sound Alarm System

With the rapid development of computer, multimedia and information processing technology, video and audio information applications are making great progress. Besides the visible information, speech and rich audio expression is the hot research topic for long. Simulation of audio location and movement with 3D effect is a virtual reality (VR) technique, which is based on the kinematics, acoustics, physiological and psychological acoustics, modern digital signal processing and multimedia technology.As the interactive technology on multi-dimensional information for man-machine–environment, 3D audio effect is gradually applied in various multimedia systems and VR systems, which are found in the fields of computer games, scientific researches and entertainment. Interaction on multi-dimensional information increases the efficiency of the communication and will be a direction of future development. In defense application, many nations and armies train their soldiers with both simulator and real equipments. Simulation of audible scene could be used as an auxiliary measurement of navigation and alarming, instead of visible approach, which helps pilots on obtaining targets'distances, movements, locations and etc.With the target alarming for pilots as the potential background of this thesis, audible location theory, HRTF (Head related transfer function) and its experiment database have been researched. Analysis on characteristics of HRTF and HRIR, exploration on the effects of multiple audio elements are carried out. With the nature of personal data, HRTF is different among peoples. When an unmatched data used as the HRTF, the location results will decrease. Research on this problem is also done and improvement is obtained.For alarming of multiple targets, supposition of multi-sound is discussed in the thesis. An alarming scheme for multiple targets is also proposed to effectively integrate various information for using in the 3D sounds.Finally, based on the CIPIC's test HRTF database, an experimental 3D-sound alarming system for multiple targets is designed and installed. The system includes a simple target simulation unit to provide the amplitude, location and other target parameters, and a collection and analysis unit for multiple targets'parameters. Experiments and perceptive tests of the system verified the techniques and schemes proposed in the thesis.