METHOD AND APPARATUS FOR DISCRIMINATING ARRIVAL BEARING OF SOUND

PURPOSE:To discriminate the arrival bearing of sound in three dimensions all around a sound pickup point by arranging bidirectional microphones and a nondirectional microphone so that the directing axes of the microphones are aligned in the close proximity, and synthesizing and operating the vectors of three signals containing sound pressure data and positive and negative direction data on the axes. CONSTITUTION:The outputs of four microphones 1 - 4 are inputted into A/D converters 9 through preamplifiers 7 and filters 8. The signals are sampled in synchronization with each output and converted into digital signals. The digital outputs of the microphones are inputted into a multiplier part 11 of an operating means through buffer memories 10. In the multiplying part 11, the outputs of the bidirectional microphones 2, 3 and 4 on the axes of X, Y and Z are multiplied by the output of the nondirectional microphone 1 on the same time axis, respectively. Thus, 3 one- dimensional vector signals containing the sound pressure data and the positive and negative data on the axes of X, Y and Z are formed. The results of the multiplications of the axes of X, Y and Z are inputted into a display processor 12a of a display means 12. In the processor 12a, 3 one-dimensional vector signals are synthesized and operated, and the vector of arrival bearing of the sound is specified.