Recording medium, digital modulation / demodulation device and digital modulation / demodulation method

摘要

The information to be recorded is divided into 8-bit long data words. Next, each data word is converted into a 14-bit long code word. This codeword is sequentially connected to a 1-bit marginal bit interposed between codewords to form a codeword sequence. The runlength of 0 in the code bit sequence is limited between 2 and 11. The 1-bit margining bit has a bit value of 0, but is changed when either the Tmin control or the Tmax control is applied to achieve run-time constraints. When the adjacent bit on both sides of the margining bit is 1, the Tmin control is applied. The Tmax control is applied when the leading P bits of the preceding codeword and the leading Q bits of the codeword following the margining bit are all 0 if P + Q = 11, in which case one of the P bit and Q bit is The bit sequence is (00000), and this bit sequence (00000) is changed to (00100).