Methods and devices for two-dimensional iterative multi-track based map detection
US8582223B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 2012 |
| Grant date | Nov 12, 2013 |
| Priority date | — |
| Expiry date | Jul 13, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2516
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Decoding data written over a plurality of tracks includes selecting a mask that accounts for Inter-Symbol-Interference, the mask including channel coefficients and defining a trellis defining a plurality of states; receiving a signal corresponding to an input pixel from each of the plurality of tracks and generating equalized samples therefrom; computing transition branch probabilities for each input vector based on a Gaussian noise distribution using the equalized samples, ideal samples and a priori probabilities of the input vector; computing forward and backward probabilities via recursions using the computed transition branch probabilities; combining the forward, backward and transition branch probabilities to generate a-posteriori probabilities for the input vector; marginalizing the a-posteriori probabilities over values of neighboring pixels to generate an a-posteriori probability for a pixel of the input vector in a given state, and decoding the pixel as a first or second logical state from the marginalized a-posteriori probabilities.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.