Applications of a new simulation model for media noise limited magnetic recording channels

Abstract

A new model for the signal dependent transition noise and partial erasure which occurs in the readback signal from thin film recording media is reviewed. This model, which is referred to as the microtrack model, has its basis in physics and can be entirely specified by three parameters of the media. It is used both as a simulation tool and for analytical calculation. Through simulation, the effect of various amounts media noise on a PR4 channel is shown. Analytically, the amount of jitter and widening effects of the noise produced by the model are examined. Also, the autocorrelation of this noise and the effect of partial erasure on it is examined.

Multidimensional signal processing and detection for storage systems with data-dependent transition noise

“…According to [2] and [29], taking an th-order Taylor series expansion of the read back impulse, the signal at the channel output can be approximated as a linear sum of the noise-free response and residual responses due to deviations around the nominal position and width of the pulse. Limiting the series expansion to the first order, the read back impulse associated to this (first-order) channel model can be approximated as (3) Defining the impulse response of the filters modeling the position jitter and width variation noise process as 1 and using this first-order approximation (3) in (1), the continuous waveform at the output of the channel can be approximated as , where we have defined as (4) A block diagram descriptive of the first-order channel model is shown in Fig. 1.…”

“…With respect to the algorithms proposed in the literature [6], [12], which deal with colored Gaussian thermal noise and transition noise, respectively, and are based on the observation of only, we can now operate on an augmented set of useful observations, allowing the described detector to outperform the previously proposed detection schemes. 3 The first matched filter in the front end in Fig. 2.…”

“…In the literature, a few channel models have been proposed to enable the analysis and design of optimum detectors, among which the microtrack model [3], the signal-dependent autoregressive channel model [4], and the position jitter and width variation model [2], [5]. The latter is used in this paper.…”

Reconfigurable Readback-Signal Generator Based on a Field-Programmable Gate Array

“…Moon [1] uses Taylor series to approximate transition jitter and width variation. Caroselli and Wolf [2] simplify the structure of recorded tracks by using a micro-track model. In our implementation, we mimic the physical reality by actually shifting the pulse position and changing the pulse shape in runtime.…”

Oversampled Detector for Transition-Noise-Limited Digital Storage Systems

“…In the literature, a few channel models have been proposed to enable the analysis and design of optimum detectors [1], [2]. In this paper the position jitter and width variation model [3], [4] is used.…”