Dynamic magnetic information storage or retrieval – General processing of a digital signal – Data clocking
Patent
1997-03-19
2000-02-01
Tokar, Michael
Dynamic magnetic information storage or retrieval
General processing of a digital signal
Data clocking
360 53, 375355, 714814, G11B 509
Patent
active
060210117
ABSTRACT:
A synchronous read channel is disclosed which samples an analog read signal from a magnetic read head positioned over a magnetic disk medium, filters the sample values according to a desired partial response, extracts timing information from the filtered sample values, and detects an estimated data sequence from the filtered sample values using a discrete time sequence detector. Discrete time timing recovery within the read channel comprises a variable frequency oscillator (VFO) for generating a sampling clock. A center operating frequency of the VFO is adjusted through a programmable register which stores a digital center frequency setting. A phase error is computed from the sample values and combined with the center frequency setting to control the frequency and phase of the sampling clock at the output of the VFO.
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Anderson Kent D.
Armstrong Alan J.
Behrens Richard T.
Dudley Trent
Foland Bill R.
Cirrus Logic Inc.
Sheerin Howard H.
Shifrin Dan A.
Tokar Michael
Wamsley Patrick
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