CHARGE-CONSTRAINED (0,G I,C) SEQUENCES

A (0, G/I) code is a modulation code used in the PRML recording system in which G and I represent the maximum number of zeros between two co nsecutive ones in the global sequence and the interleaved subsequences , respectively. For some magnetic recording systems such as the one wi th a helical scanning rotary head, a dc-balanced write waveform is req uired to meet channel requirements. In this study, charge-constrained (0, G/I; C) sequences which can generate a dc-balanced write waveform are investigated, where C represents the upper bound of charge. Based upon the runlength subgraphs and the transition matrices, capacities a nd power spectra of (0, G/I; C) sequences are derived and computed.