B. Vizvari et G. Kolumban, QUALITY EVALUATION OF RANDOM NUMBERS GENERATED BY CHAOTIC SAMPLING PHASE-LOCKED LOOPS, IEEE transactions on circuits and systems. 1, Fundamental theory andapplications, 45(3), 1998, pp. 216-224
The quality of generated random numbers is determined by the independe
nce of consecutive numbers from one another, If the random numbers are
used for enciphering plain text then correlation or periodicity destr
oys the security of the transmission, Chaotic signals are claimed to b
e suitable for secure communications; however, the quality of the gene
rated sequences has not yet been studied, Physical changes in the para
meters of the chaotic circuits used to generate random numbers may alt
er the parameters determining the chaotic behavior, i.e., the quality
of the generated random numbers, This paper evaluates the quality of r
andom sequences generated by chaotic sampling phase-locked loops (PLL'
s). It shows that micro-Feigenbaum diagrams, i.e., small periodic wind
ows, can be observed in the chaotic PLL's proposed for random number g
eneration, The run test, a much more sensitive tool than the autocorre
lation function, is used to evaluate the quality of the random numbers
, Because the results have shown that the quality of the generated num
bers does not meet the requirements, a simple method is proposed to im
prove the performance of the chaotic PLL's.