Parallel shift register generators: theory and applications to parallel scrambling in multibit-interleaved multiplexing environments

A theory is developed on parallel shift register generators (PSRG) and its parallel scrambling applications are discussed in the multibit-interleaved multiplexing environments. The PSRG is a shift register generator (SRG) which generates multiple sequences in such a way that when these multiple sequences are multibit-interleaved the resulting sequence becomes identical to some prespecified sequence. The properties of PSRGs are discussed and efficient realizations of PSRGs are examined with stress put on a special class of PSRGs for which the generating polynomials are irreducible. Finally demonstrations are given on the application of the PSRG theory to parallel scrambling of the SDH-based lightwave transmission signals STM-4 and STM-16.<>