Method for characterizing a magnetic-recording system for the presence of adjacent-track interference and far-track interference
View Patent ↗A method for characterizing a magnetic-recording system for the presence of adjacent-track interference and far-track interference. The method includes writing a plurality of repeating pulse-waveforms on a data track of a magnetic-recording disk at a write element of a magnetic-recording head. The method further includes reading a plurality of read-back signals from the magnetic-recording disk over a band of pseudo-data tracks offset from the data track by corresponding pseudo-data-track offsets in a radial direction of the magnetic-recording disk at a read element of the magnetic-recording head. In addition, the method includes displaying a magnetic-recording-signature map synthesized from the read-back signals from the magnetic-recording disk.
1. A method for characterizing a magnetic-recording system for the presence of adjacent-track interference and far-track interference, said method comprising:
writing a plurality of repeating pulse-waveforms on a data track of a magnetic-recording disk at a write element of a magnetic-recording head;
reading a plurality of read-back signals from said magnetic-recording disk over a band of pseudo-data tracks offset from said data track by corresponding pseudo-data-track offsets in a radial direction of said magnetic-recording disk at a read element of said magnetic-recording head; and
displaying a magnetic-recording-signature map synthesized from said read-back signals from said magnetic-recording disk, wherein said displaying said magnetic-recording-signature map comprises:
repeating said reading said plurality of read-back signals from said magnetic-recording disk over said band of pseudo-data tracks offset from said data track to produce an iteratively read plurality of read-back signals corresponding to said repeating of said reading;
signal averaging iteratively read pluralities of read-back signals to produce a plurality of signal-averaged, read-back signals; and
displaying a magnetic-recording-signature map synthesized from said signal-averaged, read-back signals from said magnetic-recording disk.
2. The method recited in claim 1 , wherein said plurality of repeating pulse-waveforms has a low-frequency, said low frequency defined by a distance between portions of said magnetic-recording disk written by pulse portions of said pulse-waveforms being greater than 100 nm.
3. The method recited in claim 1 , wherein a pulse-waveform of said plurality of repeating pulse-waveforms further comprises a positive pulse portion, a positive plateau portion, a negative pulse portion and a negative plateau portion.
4. The method recited in claim 3 , wherein said positive plateau portion is set at a level below a level sufficient to write said magnetic-recording disk; and
said negative plateau portion is set at a level above a level sufficient to write said magnetic-recording disk.
5. The method recited in claim 1 , wherein an outer bound of said band straddling either side of said data track lies outside of 70 nm on either side of a track center of said data track.
6. The method recited in claim 1 , further comprising:
erasing a plurality of pseudo-data tracks over a band of pseudo-data tracks offset from said data track by said corresponding pseudo-data-track offsets in said radial direction of said magnetic-recording disk at said write element of said magnetic-recording head;
wherein said erasing is a DC erasing.
7. The method recited in claim 1 , further comprising:
repeating said writing said data track on said magnetic-recording disk with said plurality of repeating pulse-waveforms.