Generation of pseudorandom binary sequences by means of linear feedback shift registers (LFSRs) with dynamic feedback

In 2002, Mita et al. proposed a pseudorandom bit generator based on a dynamic linear feedback shift register (DLFSR) for cryptographic application. The particular topology there proposed is now analyzed, allowing us to extend the results to more general cases. Maximum period and linear span values are obtained for the generated sequences, while several estimations for autocorrelation and cross‐correlation of such sequences are also presented. Furthermore, the sequences produced by DLFSRs can be considered as interleaved sequences. This fact allows us to apply the general interleaved sequence model proposed by Gong and consequently simplify their study. Finally, several remarks are stated regarding DLFSR utilization for cryptographic or code division multiple access (CDMA) applications.