发明名称 |
Echo canceller for decreasing a deterioration factor of a speech quality |
摘要 |
An echo canceller which estimates an echo gain from a reception signal level and a transmission signal level; calculates logarithmically converted power of a reception signal level; calculates logarithmically converted power of a transmission signal level; estimates an echo gain based on the reception signal level and the transmission signal level; adds the estimated echo gain to the reception signal level to obtain an estimated echo level, calculates logarithmically converted power of a residual signal level; and compares the estimated echo level with the residual signal level after echo cancellation; wherein the echo of the reception signal contained in the transmission signal is canceled when the estimated echo level exceeds the value obtained by adding a margin to the residual signal level.
|
申请公布号 |
US6445792(B1) |
申请公布日期 |
2002.09.03 |
申请号 |
US19970779128 |
申请日期 |
1997.01.06 |
申请人 |
MITSUBISHI DENKI KABUSHIKI KAISHA |
发明人 |
SHIRAKI KOICHI;KAJIYAMA IKUO |
分类号 |
H04B3/23;(IPC1-7):H04M9/08 |
主分类号 |
H04B3/23 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|