| 摘要 |
An echo cancellation device includes: a full-band echo canceller that generates a pseudo-echo signal; a downsample processor that downsamples a received signal and extracts a low-band component delayed by a delay amount D1; a delay controller that delays the low-band component by a delay amount D2; a delay controller that delays an output signal of the delay controller by a delay amount D3; a low-band echo canceller that generates a pseudo-echo signal delayed by a delay amount D1+D2; and an upsample processor that upsamples the low-band pseudo-echo signal to generate a full-band pseudo-echo signal delayed by the delay amount 2D1+D2. The delay controllers control the delay amounts D2 and D3 such that a tap length LA satisfies a condition of LA ≧2D1+D2=D2+D3, the tap length LA indicating a response time of the adaptive filter in the full-band echo canceller. |
