General transform filters in perpendicular recording architectures

Summary form only given. Unlike longitudinal recording, perpendicular recording read-back signals have a significant amount of low frequency content, which constitutes a potential problem in designing a channel architecture. One way of dealing with this problem is to transform perpendicular readback signals to a longitudinal looking one With this kind of transformation we not only get rid of the low frequency content of the perpendicular signal, but we can also use the existing longitudinal channel architectures for perpendicular recording. Up until now, only the differentiator and the Hilbert transform have been analyzed for this purpose. In this paper, we generalize this concept of transform filtering, and introduce general transform filters.