Patent ID: 6982660
Filing Date: 2006-01-03
Classification: G11B,H03M

Abstract:
1. A modulation method of a modulation apparatus for generating a channel-bit sequence from an input bit sequence and generating an output code sequence from the channel-bit sequence, the modulation method comprising: a digital sum value (DSV) control bit generating step of generating a DSV control bit inserted in the input bit sequence in order to control a DSV of the output code sequence; a DSV-control-bit inserting step of inserting the DSV control bit generated in the DSV-control-bit generating step at a predetermined position of the input bit sequence; a modulating step of modulating a post-insertion bit sequence obtained by inserting the DSV control bit into the input bit sequence, into the channel-bit sequence based on a conversion rule of a variable-length code (d, k; m, n; r); and a synchronization-signal inserting step of inserting a predetermined synchronization signal at a predetermined position of the channel-bit sequence supplied from the modulating step, wherein the DSV-control-bit generating step comprises: a modulation-delimiter detecting step of detecting a modulation delimiter that serves as a delimiter for conversion of the variable-length code; and a valid-delimiter detecting step of detecting a valid delimiter for controlling timing for determining a value of the DSV control bit, based on the modulation delimiter detected in the modulation-delimiter detecting step.