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Quality Analog Scramblers Using Frequency-Response Masking Filter Banks

  • Low Power Digital Filter Design Techniques and Their Applications
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Abstract

A very low complexity frequency-domain analog speech scrambler having high-quality speech reconstruction is proposed. The scrambler uses frequency-response masking filter banks which have low computational complexity and narrow transition widths. The proposed system does not require bandwidth expansion, and is robust for transmission channels with distortion characteristics. Preliminary investigations showed that speech scrambled using this method is nearly unintelligible to the casual eavesdropper.

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Authors and Affiliations

  1. Temasek Laboratories, Nanyang Technological University, Singapore, Singapore

    Y. C. Lim & J. W. Lee

  2. School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, Singapore

    Y. C. Lim & S. W. Foo

Authors
  1. Y. C. Lim
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  2. J. W. Lee
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  3. S. W. Foo
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Correspondence to J. W. Lee.

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Lim, Y.C., Lee, J.W. & Foo, S.W. Quality Analog Scramblers Using Frequency-Response Masking Filter Banks. Circuits Syst Signal Process 29, 135–154 (2010). https://doi.org/10.1007/s00034-009-9113-8

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  • DOI: https://doi.org/10.1007/s00034-009-9113-8

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