| 摘要 |
PURPOSE:To obtain an echo canceller giving an excellent converging characteristic to a reception side input signal having a strong correlativity such as a voice signal by providing a means to reduce the correlativity by a linear forecast model. CONSTITUTION:When a reception side input signal is inputted at first, a PARCOR coefficient calculator 3 regards the said reception side input signal as an output signal of the M order linear forecast model to obtain the PARCOR coefficient ki (i=1, 2,...,M). In the modified grating method, the PARCOR coefficient is calculated, the input signal and the PARCOR coefficient are used to eliminate the correlation included in the input signal, a linear forecast inverting filtering generating a residual signal of the input signal is applied at the same time. Thus, the PARCOR coefficient calculator 5 calculates the PARCOR coefficient of the reception side input signal, the 1st linear forecast inverse filter 6 uses the reception side input signal and the said PARCOR coefficient so as to eliminate the correlation included in the reception side input signal thereby generating the residual signal of the reception side input signal. |
