On the Effectivity of Different Pseudo-Noise and Orthogonal Sequences for Speech Encryption from Correlation Properties
We analyze the effectivity of different pseudo noise (PN) and orthogonal sequences for encrypting speech signals in terms of perceptual intelligence. Speech signal can be viewed as sequence of correlated samples and each sample as sequence of bits. The residual intelligibility of the speech signal can be reduced by removing the correlation among the speech samples. PN sequences have random like properties that help in reducing the correlation among speech samples. The mean square aperiodic auto-correlation (MSAAC) and the mean square aperiodic cross-correlation (MSACC) measures are used to test the randomness of the PN sequences. Results of the investigation show the effectivity of large Kasami sequences for this purpose among many PN sequences.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1062680Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1762
 H. J. Beker and F. C. Piper, Secure Speech Communications, London: Academic Press, 1985.
 W. Stallings, Cryptography and Network Security, Englewoods Cliffs, NJ: Prentice Hall, 2003.
 W. Diffe and M. E. Hellman, "New directions in cryptography," IEEE Trans. Inform. Theory, vol. 22, pp. 644-654, Nov. 1976.
 N. S. Jayant, B. J. McDermott, S. W. Christensen and A. M. Quinn, "A comparison of four methods for analog speech privacy," IEEE Trans. Commun., vol. COM-29, pp. 18-23, Jan. 1981.
 B. Goldburg, S. Sridharan and E. Dawson, "Design and cryptanalysis of transform based speech scramblers," IEEE J. Selected Areas Commun., vol. 11, no. 5, pp. 735-744, June 1993.
 R. L. Pickholtz, D. L. Schilling and L. B. Milstein, "Theory of spread spectrum communications ÔÇö A tutorial," IEEE Trans. Commun., vol. COM-30, no. 5, May 1982.
 E. H. Dinan and B. Jabbari, "Spreading codes for direct sequence CDMA and wideband CDMA cellular networks," IEEE Commun. Magazine, vol. 36, no. 4, pp. 48-54, Sep. 1998.
 B. Sklar, Digital Communications: Fundamentals and Applications, 2nd Ed., NJ: Prentice Hall, 2001.
 J. H. Lindholm, "An analysis of the pseudo randomness properties of the subsequences of long m-sequences," IEEE Trans. Inform. Theory, vol. IT-14, pp. 569-576, July 1968.
 I. Oppermann and B. S. Vucetic, "Complex spreading sequences with a wide range of correlation properties," IEEE Trans. Commun., vol. COM- 45, pp. 365-375, March 1997.
 L. T. Wang and E. J. McCluskey, "Linear feedback shift register design using cyclic codes," IEEE Trans. Comput., vol. 37, pp. 1302-1306, Oct. 1988.
 A. Fuster and L. J. Garcia, "An efficient algorithm to generate binary sequences for cryptographic purposes," Theoretical Computer Science, vol. 259, pp. 679-688, May 2001.
 D. V. Sarwate and M. B. Pursley, "Correlation properties of pseudo random and related sequences," Proc. IEEE, vol. 68, no. 5, pp. 593- 619, May 1980.
 S. W. Golomb and R. A. Scholtz, "Generalized Barker sequences," IEEE Trans. Inform. Theory, vol. IT-11, no. 4, pp. 533-537, Oct. 1965.
 D. G. Luenberger, "On Barker codes of even length," Proc. IEEE, vol. 51, pp. 230-231, Jan. 1963.
 C. K. Chan and W. H. Lam, "Generalised Barker-like PN sequences for quasisynchronous spread spectrum multiple access communication systems," IEE Proc. Commun., vol. 142, no. 2, pp. 91-98, April 1995.
 X. Wang, Y. Wu and B. Caron, "Transmitter identification using embedded pseudo random sequences," IEEE Trans. Broadcasting, vol. 50, no. 3, pp. 244-252, Sep. 2004.
 V. Milosevic, V. Delic and V. Senk, "Hadamard transform application in speech scrambling," Proc. IEEE, vol. 1, pp. 361-364, July 1997.
 Tai-Kuo Woo, "Orthogonal variable spreading codes for wideband CDMA," IEEE Trans. Vehicular Tech., vol. 51, no. 4, pp. 700-709, July 2002.
 B. Wysocki and T. A. Wysocki, "Modified Walsh Hadamard sequences for DS-CDMA wireless systems," School of Electrical, Computer and Telecommunications Engineering, University of Wollongong, Australia. (Online) Available: www.elec.uow.edu.au/staff/wysocki/publications/J1.pdf.
 A. Mitra, "On Pseudo-Random and Orthogonal Binary Spreading Sequences", to appear in Int. J. Info. Tech., 2007.