Invention Grant
- Patent Title: Systems and methods for variable fly height measurement
- Patent Title (中): 可变飞行高度测量的系统和方法
-
Application No.: US12669483Application Date: 2008-07-28
-
Publication No.: US08098451B2Publication Date: 2012-01-17
- Inventor: Nils Graef
- Applicant: Nils Graef
- Applicant Address: US PA Allentown
- Assignee: Agere Systems Inc.
- Current Assignee: Agere Systems Inc.
- Current Assignee Address: US PA Allentown
- Agency: Hamilton DeSanctis & Cha
- International Application: PCT/US2008/071367 WO 20080728
- International Announcement: WO2010/014078 WO 20100204
- Main IPC: G11B21/02
- IPC: G11B21/02

Abstract:
Various embodiments of the present invention provide systems and methods for determining fly height. For example, a system for fly height determination is disclosed that includes a head assembly disposed in relation to a storage medium, a write channel, and a read circuit. The read circuit is operable to receive information from both the head assembly and the write channel. A frequency determination circuit is included that is operable to receive a first signal from the read circuit corresponding to information received from the write channel and to provide a first fundamental frequency and a first higher order frequency based on the first signal, and the frequency determination circuit is operable to receive a second signal from the read circuit corresponding to information received from the head assembly channel and to provide a second fundamental frequency and a second higher order frequency based on the second signal. A compensation variable calculation module is included that is operable to divide the first fundamental frequency by the first higher order harmonic to yield a compensation variable. A fly height calculation module is included that is operable to divide the second fundamental frequency by the second higher order harmonic and the compensation variable to yield an indication of a distance between the head assembly and the storage medium.
Public/Granted literature
- US20100202082A1 Systems and Methods for Variable Fly Height Measurement Public/Granted day:2010-08-12
Information query