| 摘要 |
PURPOSE:To give a sense of direction at outside of a head by arranging sound sources for measurement in a prescribed direction in a real sound field and at a prescribed distance, approximating a head impulse response at that time with a digital filter and correcting the characteristic at receiver listening with an inverse filter the same at space listening. CONSTITUTION:A reception signal from a communication line is converted in to an ADPCM (adaptive differential PCM)/linear PCM converter 1, becomes a linear PCM signal at 16kHz sampling, the linear PCM signal is branched and inputted to digital filters 2, 3 and corrected by the prescribed impulse response characteristic and the resulting signal is sent. The head impulse response by sound sources arranged in a real sound field in a prescribed direction and at a prescribed distance is approximated and the characteristic at the listening by receivers 9a, 9b is corrected the same as that at spatial listening in the sound band. Thus, a talker in a telephone conference system receives a sense of direction with respect to ground and an utterance party is clearly identified. |
