# Partial response maximum likelihood

storage

(PRML) A method for converting the weak analog signal from the head of a magnetic disk drive into a digital signal. PRML attempts to correctly interpret even small changes in the analog signal, whereas peak detection relies on fixed thresholds. Because PRML can correctly decode a weaker signal it allows higher density recording.

For example, PRML would read the magnetic flux density pattern 70, 60, 55, 60, 70 as binary “101”, and the same for 45, 40, 30, 40, 45. A peak detector would decode everything above, say, 50 as high, and below 50 as low, so the first pattern would read “111” and the second as “000”.

(1996-12-27)

Tagged: p

Read Also:

- Partial-score
noun, Bridge. 1. . [pahrt-skawr, -skohr] /ˈpɑrtˈskɔr, -ˈskoʊr/ noun, Bridge. 1. a contract to make less than the number of tricks required for game: to bid a part-score of three diamonds. 2. the number of points gained by making such a contract: a part-score of 60 points.

- Partial seizure
partial seizure n. Focal epilepsy.

- Partial-sum
noun, Mathematics. 1. one of a series of sums of elements of a given sequence, the first sum being the first element, the second sum being the first element added to the second element, the third sum being equal to the sum of the first three elements, and so on.

- Partial-thickness flap
partial-thickness flap n. See split-thickness flap.