DC-balanced, transition-controlled, scalable encoding method and apparatus for multi-level signaling

An encoding method for multi-level signaling, wherein the encoding method is executed in a transmitter, the encoding method comprising:

• generating, at a first step, a set of candidate patterns from input data by using symbol-based inversion;
• determining, at a second step, a transmission control code by using a cumulated disparity value previously stored and a set of disparity values that is a result of calculating disparity indicating a degree to which each of the candidate patterns deviates from DC balance;
• and
• selecting, at a third step, one candidate pattern from the set of the candidate patterns as data to be transmitted, according to the determined transmission control code,
• wherein the cumulated disparity value is a result of accumulating disparity indicating a degree to which transmission data up to previous transmission deviates from DC balance.

An encoding method for multi-level signaling, wherein the encoding method is executed in a transmitter, the encoding method comprising:

• generating, from input data, a set of candidate patterns including a first pattern obtained by not inverting the input data at all, a second pattern obtained by partially inverting the input data, a third pattern obtained by partially inverting the input data, the third pattern being in a complementary relationship with the second pattern, and a fourth pattern obtained by inverting all the input data;
• and
• selecting one pattern among the first pattern to the fourth pattern as data to be transmitted, by using a cumulated disparity value previously stored and a set of disparity values that is a result of calculating disparity indicating a degree to which each of the first pattern to the fourth pattern deviates from DC balance,
• wherein the cumulated disparity value is a result of accumulating disparity indicating a degree to which transmission data up to previous transmission deviates from DC balance.