| 摘要 |
PROBLEM TO BE SOLVED: To obtain a means by which stable equalization can be performed in an asymmetric signal by connecting a symmetric FIR filter in which left and right values of a tap coefficient are symmetric and an asymmetric FIR filter in which left and right values of a tap coefficient are not symmetric in parallel to sampler output, adjusting a phase by an output of the symmetric FIR filter, and equalizing a waveform by an output of the asymmetric FIR filter. SOLUTION: A symmetric FIR filter 2 and an asymmetric FIR filter 3 are connected in parallel to an output of a sampler 1, phase adjustment is performed by a PLL circuit 4 using an output of the symmetric FIR filter 2, and an output of the asymmetric FIR filter 3 is used for input of a detector 5. As the asymmetric FIR filter 3 and the PLL circuit 4 do not interfere each other, stable equalization can be performed for an asymmetric signal. It can be incorporated in a disk storage device represented by a magnetic disk device, and a device which can perform stable reading of a signal can be realized.
|
