METHOD AND APPARATUS FOR CODING INFORMATION METHOD AND APPARATUS FOR DECODING CODED INFORMATION METHOD OF FABRICATING A RECORDING MEDIUM THE RECORDING MEDIUM AND MODULATED SIGNAL

摘要

PURPOSE: A method and an apparatus for coding information are provided to convert m-bit information words into n-bit code words at a rate greater than 2/3, whereby the same amount of information is recorded in less space, and information density increased. CONSTITUTION: An apparatus for coding information includes a converter(50), a buffer memory(54), a parallel-to-serial converter(56) and a modulator circuit(58). In operation, the converter(50) receives m-bit information words and an s-bit state word from the first bus(51) and the third bus(53), respectively. The s-bit state word indicates the state in the translation table to use in converting the m-bit information word. Accordingly, based on the value of the m-bit information word, the n-bit code word is determined from the code words in the state identified by the s-bit state word. Also, the state direction associated with the n-bit code word is determined. The state direction, namely, the value thereof is converted into an s-bit binary word or alternatively, the state directions are stored in the translation table as s-bit binary words. The converter(50) outputs the n-bit code word on the second bus(52) and outputs the s-bit state direction on fourth bus(55). The buffer memory(54) stores the s-bit state direction as a state word and supplies the s-bit state word to the converter(50) over the third bus(53) in synchronization with the receipt of the next m-bit information word by the converter(50).