公开(公告)号：JP2002074842A

公开(公告)日：2002-03-15

申请号：JP2000250679

申请日：2000-08-22

Applicant: IBM

Inventor： BUSH GREGORY SCOTT ,  JOHN JEFFREY STEPHANSON

IPC: G11B20/10

Abstract: PROBLEM TO BE SOLVED: To provide a method which prevents the gain and a timing loop from being relative to an equivalent algorithm and also eliminates restriction to be applied to the FIR tap weight. SOLUTION: The direction is calculated to move every tap weight and the new tap weight is decided in the direction of every tap weight. The gain of an FIR filter of the new tap weight is compared with its prescribed threshold. The gain of the gain loop of a data channel is incrementally controlled in response to the gain value to be compared and the prescribed gain threshold. The phase lag of the FIR filter of the new tap weight is compared with the prescribed phase lag threshold. Then the phase of a timing loop of the data channel is incrementally controlled in response to the phase lag value to be compared and the prescribed phase lag threshold.

公开(公告)号：FR2799085B1

公开(公告)日：2005-02-04

申请号：FR0011030

申请日：2000-08-29

Applicant: IBM

Inventor： BUSH GREGORY SCOTT ,  STEPHENSON JOHN JEFFREY

IPC: G11B20/10 ,  H04L7/02 ,  H04L25/03 ,  H04L27/01 ,  G06F3/06

Abstract: An equalization method and apparatus with gain adjustment are provided for a direct access storage device (DASD) data channel. A direction for moving each of a plurality of tap weights is calculated. New tap weights are determined for each of a plurality of tap weights in the direction. A gain of the FIR filter for the new tap weights is compared with a set threshold gain value. A gain of a gain loop of the data channel is incrementally adjusted responsive to the compared gain and set threshold gain values. A phase lag of the FIR filter for the new tap weights is compared with a set threshold phase lag value. A phase of a timing loop of the data channel is incrementally adjusted responsive to the compared phase lag and set threshold phase lag values.

公开(公告)号：FR2799085A1

公开(公告)日：2001-03-30

申请号：FR0011030

申请日：2000-08-29

Applicant: IBM

Inventor： BUSH GREGORY SCOTT ,  STEPHENSON JOHN JEFFREY

IPC: G11B20/10 ,  H04L7/02 ,  H04L25/03 ,  H04L27/01 ,  G06F3/06

Abstract: The equalization method determines the sense to adjust the value of each of the finite impulse response filter (FIR) coefficients, and calculates new values for each coefficient and adjusts them. The gain of the FIR under the new coefficients is compared with a predetermined gain threshold, and the gain of the gain loop of the data channel is adjusted in response to the comparison.