The invention relates to a method of multi-dimensionally encoding a user
data stream of user words into a channel data stream of channel words
evolving in a one-dimensional direction of infinite extent. The invention
relates further to a corresponding method of decoding. In order to
implement certain two- or multi-dimensional coding constraints and coding
geometries which lead to higher storage densities and improve the coding
efficiency, a method of encoding is proposed wherein:--a user word is
encoded into an NRZ channel word by selecting said NRZ channel word from
a code table depending on said user word and the current state of an
underlying finite-state-machine, wherein an NRZ channel word comprises a
sequence of NRZ channel symbols of NRZ channel bits having a
one-dimensional interpretation along said one-dimensional direction and
wherein states of an underlying finite-state-machine describing the
characteristics of the multi-dimensional code are defined by NRZI channel
bits of the previous channel word and by NRZ channel symbols of the
current channel word,--the NRZ channel symbols are transcoded into NRZI
channel symbols by a one-dimensional 1T-precoding operation including an
integration modulo 2, said 1T-precoding operation being carried out along
said one-dimensional direction of infinite extent, and--said
finite-state-machine is put into a new state selected from said code
table depending on said user word and the current state of said
finite-state-machine together with encoding a user word into a channel
word.
