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US 2006/0235916 A1Published application
System of converting information words to a signal
AssigneeKoninklijke Philips Electronics N.V.
InventorKornelis Schouhamer Immink
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AssigneeKoninklijke Philips Electronics N.V.
InventorKornelis Schouhamer Immink
Estimating the term…
A method of converting m-bit information words to a runlength constrained modulated signal is described. The available code words are distributed over at least one group (G1) of a first type and at least one group (G2) of a second type. The delivery of a code word belonging to the group of the first or second type establishes a coding state of the first type (S1) or one of a number r of coding states (S2, S3) of the second type depending on the current information word. For each information word a subset of code words is available, which subset has at least one disjunct code word for each of the r coding states. The selection from the subset of the code word to be delivered is based the coding state, on dynamically verifying the runlength constraint for the sequence of code words and on an additional criterion, like the low frequency content of the modulated signal.
Method of converting a series of m-bit information words (1) to a modulated signal (7), with m being an integer, in which method an n-bit code word (4) is delivered for each received information word (1), with n being an integer exceeding m, and the delivered code words (4) are modulated to the modulated signal (7), and in which the series of information words is converted to a series of code words so that the corresponding modulated signal (7) satisfies a predetermined criterion, and in which the code words (4) are spread over at least a group of a first type (G11,G12) and at least a group of a second type (G2), while the delivery of a code word belonging to the group of the first type (G11,G12) establishes a coding state (S1) of a first type determined by the associated group, and the delivery of a code word belonging to the group of the second type (G2) establishes one of r coding states (S2,S3) of a second type determined by the associated group and by the information word (1) associated to the delivered code word (4), in which the group of the second type comprises at least one code word being associated with at most r information words among which the respective information word is distinguishable by evaluating a predetermined parameter of the following code word,
Coding device (140) comprising an m-to-n bit converter (60) for converting the m-bit information words to n-bit code words, and means (66,68) for modulating the n-bit code words to a modulated signal, the modulated signal satisfying a predetermined criterion, and state establishing means (64) for establishing, on the delivery of a code word by the converter, a coding state of a first type (S1) for each of the delivered code words belonging to a group (G11,G12) of a first type determined by the associated group, and one of r coding states (S2,S3) of a second type for each of the delivered code words belonging to a group (G2) of the second type determined by the associated group and by the information word associated to the delivered code word, in which the group of the second type comprises at least one code word being associated with at most r information words among which the respective information word is distinguishable by evaluating a predetermined parameter of the following code word,
Signal comprising a sequence of successive signal portions (8) each corresponding to an information word, the signal satisfying a predetermined criterion, in which signal each of the signal portions (8) comprises n bit cells having a first or second signal value, a signal portion belonging to a group (G11,G12) of a first type of signal portions uniquely representing an information word, and a signal portion belonging to a group (G2) of a second type of signal portions in combination with a successive signal portion representing a unique information word, at least one signal portion of the group of the second type being associated with at most r information words among which the respective information word is distinguishable by evaluating a predetermined parameter of the successive signal portion, characterized in that the signal comprises at least one signal portion selected based on an additional criterion from a subset of signal portions excluding all signal portions not complying with said predetermined criterion and, in the event that the preceding signal portion belongs to the group of the second type, excluding all signal portions having a value of the predetermined parameter not being associated with the respective information word, and
Rendering device comprising means for reading information from a track (9) on a record carrier, which device comprises means for scanning the track and demodulation means for retrieving code words from signal portions (8) of a signal provided in the track, the signal satisfying a predetermined criterion, in which signal each of the signal portions (8) comprises n bit cells having a first or second signal value, a signal portion belonging to a group (G11,G12) of a first type of signal portions uniquely representing an information word, and a signal portion belonging to a group (G2) of a second type of signal portions in combination with a successive signal portion representing a unique information word, and a converter for converting the code words into information words, the converter comprising means for distinguishing the respective information word by evaluating a predetermined parameter of the following code word,
Dependencies are inferred from the claim text.