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Counterfeit Deterrent Features for the Next-Generation Currency Design (1993) / Chapter Skim
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Appendix E: Methods for Authentication of Unique Random Patterns
Pages 117-120

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From page 117...
... Similarly, when a large number of unlike patterns are read and correlated, they will generate a different distribution with a peak at a lower value. If there is a complete separation between these curves, a threshold correlation value between the peaks can be selected such that all correlation numbers below that value result from correlation of unlike pattern descriptions and all correlation values above the threshold number result from correlation of like pattern descriptions.
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From page 118...
... In the application for arms control verification mentioned above, substantial effort was devoted to adversary analysis to ensure that the random patterns could not be counterfeited successfully and that both the false negatives and false positives resulting from correlations of pattern readings taken in the field would be less than one in a million. A simple method for minimizing concerns regarding misalignment of the reader with the pattern on successive readings is to desensitize the special resolution of the pattern reading.
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From page 119...
... .OCatlOnS IS NNR =np 2 Thus, the expected ratio R of matching transparencies in the registered position to the matching transparencies in the unregistered position is _ Nr _ up _ 1 R- - _ NNR Up p If damage to the pattern causes a loss of transparencies equal to k times the original number of transparencies, the expected number of matching patterns in the registered position of the patterns is NR=n (P-kp) The expected number of matching transparencies in the unregistered position is NNR =n ~ p kp ~ p The expected ratio of matching transparencies in the registered position to the matching transparencies in the unregistered position then is R NR _ n ~ p-kP)
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From page 120...
... University of New Mexico memo to Don Bauder, Sandia National Laboratories. August.
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Key Terms

  • pattern descriptions
  • random patterns
  • sandia national
  • registered position
  • reading errors

  • unregistered position
  • false decisions
  • arms control
  • correlation value
  • expected ratio

  • pattern reading
  • regarding misalignment
  • complete separation
  • errors employs
  • unregistered orientations

  • identified methods
  • decision correlation
  • true pattern
  • unlike patterns
  • transform coefficients

  • orientations exceeding
  • correct alignment
  • correlation values
  • label counterfeit
  • control verification

  • errors mentioned
  • entire pattern
  • using transforms
  • pattern readings
  • acceptable probability


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