| 摘要 |
A far end signal from a far end user and broadcasting the far end signal at a loudspeaker is received. A signal for use in an echo transfer function is determined, and the signal selected from between: the far end signal or an echo reference signal received from a near field microphone disposed in close proximity to the speaker. The near field microphone sensing the far end signal that is broadcast from the speaker while sensing the near-end speech and ambient noise at insignificant energy levels compared to the speaker signal. An echo transfer function is determined based at least in part upon the selected signal, and the echo transfer function represents characteristics of an acoustic path between the loudspeaker and a far field microphone that is disposed at a greater distance from the speaker than the near field microphone. An estimated echo is determined based at least in part upon the echo transfer function. The estimated echo is subtracted from a signal received from the far field microphone, the subtracting effective to cancel an echo present in the signal received from the far end microphone. |
