AN EMBEDDED SERVO SYSTEM WITH REDUCED AGC OVERHEAD

摘要

The prerecorded embedded servo field (300) of this invention provides an enhanced level of functionality without increasing the servo field overhead. A prerecorded embedded servo field (300) includes a first sub-field (302) of prerecorded information that simultaneously provides (i) automatic gain control data for a third sub-field (306) and (ii) data for a first servo function, and a second sub-field (302) of prerecorded information that simultaneously provides (i) automatic gain control (AGC) data for the third sub-field (306) and (ii) data for a second servo function. Since the first and the second sub-fields (302, 303) in the servo field (300) of this invention are used for AGC and another servo function, the sub-fields are arranged within the servo field (300) so that the sub-field (302) that requires the least precise AGC control is first and the sub-field (306) that requires the most precise AGC control is last.