| 摘要 |
The invention provides methods and apparatus for encoding binary data (a) by which an improved sequence of encoded binary digits (d) suitable for NRZI modulation to produce a recording signal (e) is obtained. The sequence of encoded binary digits (d) obtained consists of a plurality of binary digit blocks (Bn), each of which is formed with a predetermined number (n) of the encoded binary digits (b) obtained from the binary data (a) and redundant codes (J), each of which is inserted between each successive two of the binary digit blocks (Bn), and can produce the recording signal (e) forming a rectangular pulse train with a waveform which has a long minimum run length and does not contain a DC component or contains a reduced DC component when it is NRZI modulated. |
