| 摘要 |
An adaptive filter unit 103 outputs a send-mid signal obtained by eliminating echo from a send-in signal, and a power comparing unit 107 calculates a power ratio between received signal power and send-mid signal power. When a receiver ST detecting unit 104 detects a single talk state at a receiving side, an acoustic coupling amount estimating unit 108 estimates and updates the estimated amount of acoustic coupling from the power ratio. A residual echo power estimating unit 109 estimates estimated residual echo power from the received signal power and the estimated amount of acoustic coupling, and a signal-to-echo ratio estimating unit 110 estimates a ratio between the send-mid signal power and the estimated residual echo power. An amplitude suppression coefficient determining unit 111 determines the amplitude suppression coefficient corresponding to the ratio, and an amplitude suppression unit 112 amplitude suppresses the send-mid signal. |
