RANDOM NUMBER GENERATOR AND METHOD FOR GENERATING RANDOM NUMBER

PROBLEM TO BE SOLVED: To provide a random number generator and a method for generating random numbers without requiring a deterministic post processing. SOLUTION: In the method, oscillation digital output signals A1, A2, ..., ALof a nonuniform or uniform cycle are generated by at least two ring oscillators 32, 33, 34. An external parity signal PS representing logic state '1' or '2' is generated when the odd number of the output signals A1, A2, ..., ALattain the specified logic state '1'. The external parity signal PS is fed back to the external parity inputs 36, 37, 38 of the respective ring oscillators. The cooperation with chaos theory (the feedback of the parity signal) and a true random nature (jitter caused by thermal noise) in a digital circuit derives an efficient and practical solution as a new theoretical principle which generates the random numbers. COPYRIGHT: (C)2006,JPO&NCIPI