Noise reduction in same-gap servo in frequency-based servo tape systems
US7623318B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 19, 2008 |
| Grant date | Nov 24, 2009 |
| Priority date | — |
| Expiry date | Jun 19, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/440263
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Noise in a same-gap, frequency-based servo tape system is reduced by applying correlated noise factors, generated during calibration, to filtered data write signals. The resulting noise values are subtracted from filtered servo signals, at frequencies F1 and F2, to generate first and second noise-compensated servo signals at frequencies F1 and F2. In one embodiment, the F1 and F2 data signals are filtered through two SOBP filters which output the magnitudes of the signals. The F1 and F2 servo signals are similarly filtered. In another embodiment, the F1 and F2 data signals are filtered through two Goertzel filters which output the real and imaginary components of the signals and the F1 and F2 servo signals are similarly filtered through two other Goertzel filters. Correlated noise factors are applied to the outputs of the write data Goertzel filters and the results subtracted from the corresponding outputs of the servo Goertzel filters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.