Coder and a method of coding for codes having a Repeated Maximum Transition Run constraint of 2
AssigneeKoninklijke Philips Electronics N.V.
InventorWillem Marie Julia Marcel Coene
Life of this patent
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Abstract
Presently known codes have long trains consisting of 2T runs that reduce the performance of the bit detector. By using a code with an RMTR constraint of 2 an improvement in the bit detection is achieved. A code constructed is a systematic way that provides an RMTR constraint of 2 is presented. Several variations of such a code are disclosed where one or more sub-codes are used, where coding states are divided into coding classes and where code words are divided into code word types. Then, for a given sub-code, a code word type t can be concatenated with a code word of the next sub-code if the subsequent code word of the next sub-code belongs to one of coding states of the coding class with index Tmax+1−t.
Claims64
A method of converting a user bitstream into a coded bitstream by means of an overall channel code comprising the steps of
- converting M-bit information words into N-bit code words,
- realizing said overall channel code by concatenating a number S of sub-codes in a cyclically repeated order with a predetermined repeat period, wherein each of the sub-codes receives mi-bit information words, wherein mi is an integer characteristic for each of the sub-codes, that are converted into ni-bit code words, wherein ni is an integer characteristic for each of the sub-codes, and wherein for each sub-code, said characteristic integer number ni is greater than said characteristic integer number mi, such that a sum of the mi-numbers of all sub-codes within said repeat period equals M, and that a sum of the ni-numbers of all sub-codes within said repeat period equals N, and:
- dividing for each sub-code, its ni-bit code words into a number of Tmax different code-word types and arranging its ni-bit code words into Tmax coding classes of coding states such that, for a given sub-code, an ni-bit code word of type t, wherein t is an integer number between 1 and Tmax, can be concatenated into a concatenated set of code words, realizing said N-bit code-words of said overall channel code that generates said coded bitstream, with an ni+1-bit code word of the next sub-code if a subsequent code word of said next sub-code belongs to one of coding states of the coding class with index Tmax+1−t.
A coder for of converting a user bitstream into a coded bitstream by means of an overall channel code by converting M-bit information words into N-bit code words, the coder comprising sub-coders repeated in a cyclical order with a predetermined repeat period, each sub-coder using a sub-code, wherein each sub-coder is arranged to receive mi-bit information words, wherein mi is an integer characteristic for each of the sub-codes, and is arranged to convert the received mi-bit information words into ni-bit code words, wherein ni is an integer characteristic for each of the sub-codes, and wherein for each sub-code, said characteristic integer number ni is greater than said characteristic integer number mi, such that the sum of the mi-numbers of all sub-codes within said repeat period equals M, and that the sum of the ni-numbers of all sub-codes within said repeat period equals N, wherein for each sub-code, its ni-bit code words are divided into a number of Tmax different code-word types and arranging its ni-bit code words into Tmax coding classes of coding states such that, for a given sub-code, an ni-bit code word of type t, wherein t is an integer number between 1 and Tmax, can be concatenated into a concatenated set of code words thus generating said coded bitstream and realizing said N-bit code-words of said overall channel code, with an ni+1-bit code word of the next sub-code if said subsequent code word of said next sub-code belongs to one of coding states of the coding class with index Tmax+1−t.
Dependencies are inferred from the claim text.