Patent ID: 7453663
Filing Date: 2008-11-18
Classification: G11B

Abstract:
1. A disk drive comprising: a rotatable disk, wherein the disk comprises a first type of servo burst pattern in a first radial spoke of the disk, and a second type of servo burst pattern in a second radial spoke of the disk, the first and second types of servo burst patterns are radially offset from each other and are associated with a plurality of data tracks extending through the first and second radial spokes, the first type of servo burst pattern comprises a first preamble and a plurality of servo bursts occupying defined servo burst positions relative to one another, the first preamble and a particular one of the first servo bursts at a particular one of the servo burst positions have a first relative phase therebetween, and the second type of servo burst pattern comprises a second preamble and a second plurality of servo bursts occupying the same defined servo burst positions relative to one another as defined for the first type of servo burst pattern, the second preamble and a particular one of the second servo bursts at the particular one of the servo burst positions have a second relative phase therebetween, wherein the first relative phase is different than the second relative phase; and a controller that is configured to control positioning of a transducer relative to the tracks on the disk based on a sensed one of the first and second servo burst patterns, wherein the controller is configured to vary a contribution of the sensed servo burst pattern to positioning of the transducer based on identifying the sensed servo burst pattern as one or the other of the first and second types of servo burst patterns in response to the difference between the first and second relative phases.