公开(公告)号：JPH10233060A

公开(公告)日：1998-09-02

申请号：JP5998

申请日：1998-01-05

Applicant: IBM

Inventor： ERIC ROLPH CHRISTENSEN ,  ROBERT ALLEN HUTCHINS ,  ARA SARUKIS PATAPOUTIAN

IPC: G11B5/09 ,  G11B7/005 ,  G11B20/10

Abstract: PROBLEM TO BE SOLVED: To obtain the threshold tracking method to be adaptable to easy updating, altering and modifying by attenuating a new envelope follower value by a programable threshold attenuating factor and providing a programable threshold generator for generating a threshold signal. SOLUTION: A discriminated positive peak signal on a line 28 is compared with a positive threshold tracking signal on a line 29 by a comparator 30. A gate signal for gating the discriminating positive peak signal from the line 28 to a register 32 is generated by the comparator 30. A digital amplitude of the last recognized peak is stored by the register 32. The peak is given to an error generating block 36 for the purpose of comparison with a value in a positive envelope follower. A generated error is given to a register 46. This positive or negative error is multiplied by a programable gain coefft. given on a line 50, and is then added to the stored value in the envelope follower, so as to update the envelope follower.