| 摘要 |
PURPOSE:To obtain a feedback type equalizer using a transversal filter having the improved approximate degree at the tail part of an impulse replay, by giving the weighting to the equalizing step. CONSTITUTION:The signals supplied from a terminal OUT are successively delayed by a delaying circuit T, and these delayed signals are delivered through a coefficient unit K with the levels in accordance with the set tap coefficients ao-an and applied to a subtractor SUB to be subtracted from the input signal. In this case, if the first M units of sample values of an impulse reply are less than an amplitude S and over an amplitude kS(k<1) and the rest N units of sample values are less than an amplitude ks, the first M units sample values are quantized with a quantizing step DELTA and the rest N units of sample values are quantized with a quantizing step kDELTA174F(K<1) respectively. Thus the approximate degree is improved at the tail part of the impulse reply by giving the weight (k) to the quantizing step. As a result, the quantizing accuracy is increased. |
