Patent ID: 6987633
Filing Date: 2006-01-17
Classification: G11B

Abstract:
1. A method to read calibration information from a tape information storage medium while acquiring a plurality of valid calibration signals, wherein said tape medium includes a calibration region comprising the steps of: providing (N) read/detect channels, wherein each of said (N) read/detect channels comprises a PLL circuit having a first PLL component interconnected with a second PLL component, wherein said first PLL component comprises a phase detector, a first loop filter having a first gain, and a first phase integrator; setting a valid calibration signal threshold; detecting at a first time the (i)th valid calibration signal, wherein (i) is greater than or equal to 1 and less than or equal to (N); determining at said first time the frequency and phase of said (i)th valid calibration signal using the first PLL component disposed in the (i)th read/detect channel; determining if said valid calibration signal threshold is exceeded; operative if said valid calibration signal threshold is exceeded, providing said frequency and phase to said second PLL component; reading information encoded on said tape medium using said second PLL component.