On the linear complexity of nonlinearly filtered PN-sequences
A method of analysis for the linear complexity of nonlinearly filtered PN-sequences is presented. The procedure provides a general lower bound for the linear complexity and an algorithm to improve it. The results obtained are valid for any nonlinear function with a unique term of maximum order and for any maximal-length LFSR. This work, which has as starting point “the root presence test” by Rueppel, is based on the handling of binary strings instead of determinants in a finite field.
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- E.J. Groth, Generation of binary sequences with controllable complexity, IEEE Trans. Inform. Theory, vol. IT-17, pp. 288–296, May 1971.Google Scholar
- E.L. Key, An analysis of the structure and complexity of nonlinear binary sequence generators, IEEE Trans. Inform. Theory, vol. IT-22, pp. 732–736, Nov. 1976.Google Scholar
- P. V. Kumar and R. A. Scholtz, Bounds on the linear span of bent sequences, IEEE Trans. Inform. Theory, vol. IT-29, pp. 854–862, Nov. 1983.Google Scholar
- J.L. Massey, Shift-Register synthesis and BCH decoding, IEEE Trans. Inform. Theory, vol. IT-15, Jan. 1969.Google Scholar
- J.L. Massey, Seminar Cryptography: Fundamentals and applications, Zurich, 1990.Google Scholar
- W.W. Peterson and E.J. Weldon, Error-Correcting Codes, Cambridge, MA: MIT Press, 1972.Google Scholar
- R.A Rueppel, Analysis and design of stream ciphers, Springer-Verlag, New York, 1986.Google Scholar