Patent ID: 7839590
Filing Date: 2010-11-23
Classification: G11B

Abstract:
1. A perpendicular magnetic recording system, comprising: a magnetic head for recording and reproducing information; and a perpendicular magnetic recording medium having a perpendicular recording layer including a servo area with a magnetic head positioning signal recorded therein and a user data area with user data recorded therein, wherein the servo area includes a burst area having a hound's tooth check pattern including a first area with a burst signal recorded therein and a second area with a dummy signal recorded therein, said second area surrounds the first area in a track direction and in a track width direction in the burst area, the burst signal provides radial direction positional information, and the dummy signal reduces a demagnetization field, wherein a frequency of the dummy signal is higher than a frequency of the burst signal, and the dummy signal is not used for positioning, and wherein the frequency of said dummy signal is twice as high as the frequency of the burst signal.