ECHO CANCELLING METHOD, ECHO CANCELLING DEVICE, AND ECHO CANCELLING PROGRAM

摘要

PROBLEM TO BE SOLVED: To cancel an echo signal, with a simple structure and a small operation amount, from a sound collection signal collected in a sampling period which does not necessarily accord with the sampling period of a reception signal.

SOLUTION: There is provided an echo cancelling device that comprises: a correlation value calculation unit 310 which calculates a correlation value between a reception signal and a sound collection signal at certain time intervals; an expansion/contraction coefficient calculation unit 320 which detects a variation in a peak position of the correlation value over time to estimate the size of a sampling period differential between a reception signal and a sound collection signal, and calculates an expansion/contraction coefficient α from the sampling period differential; a reception signal interpolation unit 330 which, by using the reception signal, the expansion/contraction coefficient α, and an interpolation formula, estimates an interpolation reception signal obtained when multiplying the sampling period of the reception signal by α; an echo simulation unit 110 which calculates a pseudo echo signal from the interpolation reception signal and a transmission signal; and a differential signal generation unit 120 which calculates the transmission signal as a differential between the sound collection signal and the pseudo echo signal.

COPYRIGHT: (C)2012,JPO&INPIT