Close loop method for measuring head SNR and media SNR
US8634157B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 12, 2011 |
| Grant date | Jan 21, 2014 |
| Priority date | — |
| Expiry date | Jul 23, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B19/048
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A close loop method for measuring head SNR, for a storage device comprising a storage media and a head, comprising steps of: (a) loading the head on the media with a dynamic fly height; (b) measuring an initial environmental temperature value T1 and measuring the head signal signalload; (c) unloading the head; (d) adjusting a power which controls the dynamic fly height until a real-time environmental temperature value T2 is equal to the initial environmental temperature T1; (e) measuring the head noise value noiseunload, (f) calculating the head SNR with the follow equation:The method of the present invention can obtain a fair condition between the signal and noise measurement, thereby a reliable and accurate head SNR can be obtain. The present invention also provides a close loop method for measuring media SNR.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.