| 摘要 |
PROBLEM TO BE SOLVED: To provide a howling preventing apparatus which estimates a loop gain and accurately prevents the occurrence of howling. SOLUTION: A superimposing section 15 superimposes pseudo noise (M sequence) on sound collected by a microphone 11 and outputs a result to an amplification system. A correlation arithmetic operating section 20 calculates a correlation between the sound collected by the microphone 11 and the pseudo noise. The correlation arithmetic operating section 20 estimates a loop gain on the basis of a correlation value and suppresses a gain of an audio signal in accordance with the estimated loop gain. Furthermore, a howling detecting section 22 inputs an audio signal collected by the microphone 11 and detects whether howling occurs. When howling occurs, a gain of a post-stage volume 14 is suppressed. COPYRIGHT: (C)2011,JPO&INPIT |
