An echo canceler which can perform the training of echo path estimation without causing any hindrance to calls. The echo canceler is equipped with a pseudo-noise generating section which generates specific training signals (pseudo-noise) which is forcedly supplied to a transmission line for transmitting the voice of a far-end talker. When the transmission level of the far-end talker is very low or when no voice is transmitted, a certain correlation is established between the pseudo-noise and the signal of the transmission line. Based on such a correlation, coefficients for generating a pseudo-echo are calculated. Therefore, the training of echo path estimation is performed based on the pseudo-noise without using the voice of the far-end talker, and an adequate pseudo-echo is produced.
申请公布号
WO9531052(A1)
申请公布日期
1995.11.16
申请号
WO1995JP00866
申请日期
1995.05.02
申请人
NTT MOBILE COMMUNICATIONS NETWORK INC.;KAWAHARA, TOSHIRO;MIKI, TOSHIO;SUDA, HIROHITO;OHYA, TOMOYUKI;TAKAGI, HIROFUMI