A secure analog speech scrambler using the discrete cosine transform

  • B. Goldburg
  • E. Dawson
  • S. Sridharan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 739)


A secure technique for analog speech encryption is described which uses the Discrete Cosine Transform (DCT). The paper shows how the proposed technique overcomes weaknesses identified in other analog scramblers by using transform domain permutation and the insertion of dummy transform components. It is shown that the DCT scrambler with dummy spectrum insertion offers a similar level of security to a digital scrambler on a bandlimited channel while providing better quality of recovered speech.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • B. Goldburg
    • 1
  • E. Dawson
    • 2
  • S. Sridharan
    • 3
  1. 1.School of Electrical and Electronic Systems EngineeringQueensland University of TechnologyBrisbaneAustralia
  2. 2.School of Mathematics and Information Security Research CentreQueensland University of TechnologyBrisbaneAustralia
  3. 3.School of Electrical EngineeringUniversity of Technology SydneySydneyAustralia

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