| 摘要 |
PROBLEM TO BE SOLVED: To obtain a highly reliable data retrieval method by continuing reading at the beginning of drop-out with a sample filter device, and continuing recovering data to be lost at an early period. SOLUTION: A signal which passes through an AGC block is added to a FFE(feed forward equalizer) 24. The FFE has a limited impulse response filter 66, a bank 68 of coefficient condensers 69, and a circuit 70. The circuit 70 makes the coefficients adaptive to reduce an error between an output on a line 72 and a reference value generated by a reference generator 74. Namely, when a coefficient monitored exceeds a specified threshold value, one of the coefficients is reset to each default value by monitoring at least one of the coefficients. Since this processing is repeated until a stable set of the coefficients are re-established, it is possible to restart a recovery of data before a signal drop-out has completely passed through. |
