Multidimensional modulation codes and error correction for page-oriented optical data storage

As with any other data storage technology, page-oriented optical data storage (PODS) systems require signal coding techniques to overcome the effects of spatial intersymbol interference (ISI), system noise and storage material defects. We describe a novel two-dimensional (2-D) modulation coding scheme for mapping digital data to the recorded patterns in the optical storage medium. This modulation coding technique overcomes the effects of spatial ISI while maximizing the useful information capacity in PODS systems. We also present 3-D interleaved error correcting coding (ECC) schemes based on Reed-Solomon (RS) codes. The ECC helps to overcome material defects and other errors, including any remaining ISI, to further improve the overall PODS system performance. We present simulation results and demonstrate how these coding methods significantly improve system performance.