| 摘要 |
<p>A wide band echo canceller (EC2) comprising:
- means (SP1) for splitting a signal (TXi) transmitted from a near end terminal to a far end terminal, into a sub-sampled signal (TH) corresponding to a higher frequency sub-band of the signal (TXi) transmitted to the far end terminal, and a sub-sampled signal (TL) corresponding to a lower frequency sub-band of the signal (TXi) transmitted to the far end terminal,
- means (SP2) for splitting a signal (RXi) received from a far end terminal into a sub-sampled signal (RH) corresponding to a higher frequency sub-band of the signal (RXi) received from the far end terminal, and a sub-sampled signal (RL) corresponding to a lower frequency sub-band of the signal (RXi) received from the far end terminal,
- a first adaptive filter (AL) for filtering the sub-sampled signal (TL) corresponding to the lower frequency sub-band,
- a second adaptive filter (AH) for filtering the sub-sampled signal (TH) corresponding to the higher frequency sub-band,
- subtracting means (SL, SH) controlling the adaptive filters (AL, AH),
- means (MX) for mixing two process corrected signals (CRL', CRH') and up-sampling the resulting signal,
- control means (CTR, STL, STH) that control the adaptation of the first adaptive filter (AL) and the adaptation of the second adaptive filter (HL) so that these two adaptations are never simultaneous.</p> |
