| 摘要 |
PURPOSE:To provide a speaker selective unit for an audio conferece terminal which enables selecting specific speaker with no additional circuits. CONSTITUTION:Nondirectional microphones L and R, 103 and 104, are provided at both ends and a speaker 105 which radiates received voice sound is provided at the central part. Further, a delay time setting part 108 which decides the delay time of transmitted voice from the microphones L and R, 103 and 104, variable time delaying equipment L and R, 106 and 107, which delays transmitted voice signal by using the delay time setting part 108, a common-mode voice extracting part 109 which takes out common-mode component out of the variable time delaying equipment L and R, 106 and 107, a pseudo echo generating part 111 which anticipates sneak path signal from the received voice signal and a subtractor 110 which removes pseudo echo out of the common-mode voice signal are provided. |
