Code-word complementing block modulation code for holographic data storage

Abstract

The holographic digital data storage (HDDS) system has been investigated for next generation digital storage due to its high storage density and high data transfer rates (J.F. Heanue et al., Science, pp. 749-752, 1994). Various modulation codes have been introduced to mitigate noise problems in HDDS systems (H.J. Coufal et al., Holographic Data Storage, Springer 2000). In this paper, a new 2D modulation scheme, or CCBM (code-word complementing block modulation), is proposed. The CCBM yields a pseudo-random array consisting of codewords with multiple weights (K. Kim et al., Proc. Satellite ISOM 2000, pp. 46-47, 2000; E. Hwang et al., Tech. Dig. ISOM 2001, pp. 142-143, 2001), and consequently gives spectral smoothing and constant energy in the modulated pages of data. This paper also covers a novel detection scheme in conjunction with the proposed CCBM. The results of numerical simulations and actual recording experiments are presented to verify the performances of CCBM. In a noisy HDDS channel, the results show that CCBM outperforms the guided scrambling (GS) method in terms of SNR and BER (bit error rate).