A method of reading servo wedge data from a rotating constant-density magnetic storage medium having a plurality of tracks, where each track is written at a track pattern frequency, the respective track pattern frequencies varying from a lowest frequency at an innermost one of the tracks to a highest frequency at an outermost one of the tracks, includes, for each respective track, determining, based on the pattern frequency of the respective track, a desired sampling position, sampling actual samples of servo wedge data based on a sampling clock used for all tracks, having a sampling frequency at least equal to the track pattern frequency of the outermost track, determining a phase relationship of the desired sampling position to the sampling clock, and, depending on the phase relationship between the sampling position and the sampling clock, interpolating a sample, or omitting interpolation of a sample and squelching the interpolation clock.

An apparatus may comprise a circuit configured to receive first underlying data corresponding to a first signal and receive a second signal corresponding to second underlying data. The circuit may determine an interference component signal based on the first underlying data corresponding to the first signal and a first channel pulse response shape for the first signal, determine estimated decisions corresponding to the second signal based on the second signal, and determine an estimated signal based on the estimated decisions corresponding to the second signal and a second channel pulse response shape for the second signal. The circuit may then generate a remaining signal based on the estimated signal and the second signal, generate an error signal based on the interference component signal and the remaining signal, and adapt one or more parameters of the first channel pulse response shape based on the error signal.

Storage device self-servo-write includes generating a time base frequency signal, generating a sampled frequency signal by sampling the time base frequency signal at a sample rate to obtain a first set of samples, decimating those samples at a decimation rate to obtain a second set of samples at a spiral frequency of which the time base frequency is a first integer multiple, detecting a spiral track based on the spiral frequency, and writing a servo pattern based on the spiral track and the time base frequency. A generated sampled frequency obtained by sampling the time base frequency signal at the sample rate is used as the servo write frequency, of which the time base frequency is a second integer multiple. Alternatively, the time base frequency is multiplied by a first rational multiple so that the time base frequency is a second rational multiple of the servo write frequency.

A method of reading servo wedge data from a rotating constant-density magnetic storage medium having a plurality of tracks, where each track is written at a track pattern frequency, the respective track pattern frequencies varying from a lowest frequency at an innermost one of the tracks to a highest frequency at an outermost one of the tracks, includes, for each respective track, determining, based on the pattern frequency of the respective track, a desired sampling position, sampling actual samples of servo wedge data based on a sampling clock used for all tracks, having a sampling frequency at least equal to the track pattern frequency of the outermost track, determining a phase relationship of the desired sampling position to the sampling clock, and, depending on the phase relationship between the sampling position and the sampling clock, interpolating a sample, or omitting interpolation of a sample and squelching the interpolation clock.

An apparatus may comprise a circuit configured to receive first underlying data corresponding to a first signal and receive a second signal corresponding to second underlying data. The circuit may determine an interference component signal based on the first underlying data corresponding to the first signal and a first channel pulse response shape for the first signal, determine estimated decisions corresponding to the second signal based on the second signal, and determine an estimated signal based on the estimated decisions corresponding to the second signal and a second channel pulse response shape for the second signal. The circuit may then generate a remaining signal based on the estimated signal and the second signal, generate an error signal based on the interference component signal and the remaining signal, and adapt one or more parameters of the first channel pulse response shape based on the error signal.

In some implementations, a system includes a magnetic media disk and a read/write unit. The read/write unit includes a plurality of phase-locked loops (PLLs), an interpolator unit, a delay-locked loop, and a precompensation unit. The PLLs are configured to generate, using a reference clock signal, a first plurality of clock signals having different frequencies phases. The interpolator unit is configured to interpolate the first plurality of clock signals in accordance with a frequency offset signal to generate a single-phase clock signal. The delay-locked loop is configured to delay the single-phase clock signal in accordance with a PLL data clock signal to generate a second plurality of clock signals having different phases. The precompensation unit is configured to apply precompensation to the second plurality of clock signals to generate a timing signal for writing data to the magnetic media disk.

In one general embodiment, a method includes determining a sampling interval for an interpolator using at least one parameter. The method further includes applying the sampling interval to the interpolator in response to determining the sampling interval. In another general embodiment, an apparatus includes an interpolator and a controller. The controller is configured to determine a sampling interval for the interpolator using at least one parameter. The controller is also configured to apply the sampling interval to the interpolator in response to determining the sampling interval.

In one general embodiment, a method includes determining a sampling interval for an interpolator using at least one parameter. The method further includes applying the sampling interval to the interpolator in response to determining the sampling interval. In another general embodiment, an apparatus includes an interpolator and a controller. The controller is configured to determine a sampling interval for the interpolator using at least one parameter. The controller is also configured to apply the sampling interval to the interpolator in response to determining the sampling interval.

In one general embodiment, a method includes determining a sampling interval for an interpolator using at least one of: predefined data stored in memory, and a standard deviation of a position error signal. The method further includes applying the sampling interval to the interpolator in response to determining the sampling interval. In another general embodiment, an apparatus includes an interpolator and a controller. The controller is configured to determine a sampling interval for the interpolator using at least one of: predefined data stored in memory, and a standard deviation of a position error signal. The controller is also configured to apply the sampling interval to the interpolator in response to determining the sampling interval.