Development of a dual-stage tracking servo using oversample technique

The sample rate is one of the main factors limiting the servo bandwidth in HDDs. This paper presents a servo design method using an oversample technique. With this method, the sample rate needed is reduced to half of the normal requirement. The performance of the oversample system remains similar to the single-rate design with twice the sample rate. The technique has been successfully applied to a dual-stage servo design and the implementation results show the applicability of the proposed technique.