| 摘要 |
<p>This invention relates to adaptive digital filters for echo cancellation in a bi-directional data transmission channel. Substantial hardware savings for a digital adaptive filter are possible, if hardware structures for performing filter operations are shared. In a digital adaptive filter with resource sharing filter operations are performed sequentially with a limited number of hardware structures. This invention discloses a digital adaptive filter with resource sharing with further hardware savings (Fig. 3). Corresponding to a characteristic decrease of the magnitude of the filter coefficients for echo cancellation, a first and second filter computation means (4A,4B) are connected to a coefficient storage means (3) with a different bit width to receive coefficients (c0, c1...cN/2-2, cN/2-1; cN/2, cN/2+1...cN-2, cN-1) having different magnitudes and/or a first and second coefficient adapting means (7A,7B) are connected to the coefficient storage means (3) with a different bit width to receive coefficients (c0, c1...cN/2-2, cN/2-1; cN/2, cN/2+1...cN-2, cN-1) having different magnitudes, allowing a hardware reduction the and reduction of the size of the filter device. <IMAGE></p> |
