Patent EA-003160-B1 (EA)
Title: A RANDOM NUMBER GENERATOR BASED ON THE SPONTANEOUS alpha-DECAY
Inventor: FIGOTIN ALEXANDR
IPC: G06F7/58
Filed: 1999-12-14
Abstract: 1. An apparatus for generation of random numbers comprising: a source of alpha decay particles; a detector of said alpha decay particles, said detector disposed in a position relative to said source to detect said alpha decay particles and generating an electric pulse in response to detection of said alpha decay particles a selective discriminator coupled to said detector to identify detection signals corresponding to an actual detection of said alpha decay particles from said source; and an binary generator coupled to said discriminator to generate a binary signal in response to positive identification by said discriminator of said detection signals corresponding to an actual detection of said alpha decay particles from said source wherein said binary generator is a clocked time comparator circuit which measures successive time intervals between successive positively identified detection signals corresponding to actual detections of said alpha decay particles from said source and which assigns a binary value to said successive time intervals depending on comparative time lengths of said successive time intervals. 2. The apparatus of claim 1 wherein said source has a half-life equal to or longer than 100 years, and decay products which do not produce alpha-radiation. 3. The apparatus of claim 1 wherein said source is Am 241. 4. The apparatus of claim 1 wherein said detector selectively detects only alpha decay products only from said source. 5. The apparatus of claim 1 wherein the shape of the electric pulse produced by said detector in response to every alpha-particle emitted from said source and having reached the detector is unique and distinctive from that produced by any other ionizing particles or radiation that can reach said detector. 6. The apparatus of claim 5 wherein said detector is shielded from nuclear, electromagnetic and optical radiation external to said source. 7. The apparatus of claim 1 wherein said selective discriminator comprises a differential discriminator to determine if said detection signal has an amplitude characteristic of said detection of said alpha decay particles. 8. The apparatus of claim 1 wherein said selective discriminator comprises a logical selector to determine if said detection signal has a shape characteristic of said detection of said alpha decay particles. 9. The apparatus of claim 7 wherein said selective discriminator comprises a logical selector to determine if said detection signal has a shape of said detection of said alpha decay particles. 10. The apparatus of claim 1 wherein said binary generator is a clocked trigger circuit which toggles with each positively identified detection signal corresponding to an actual detection of said alpha decay particles from said source. 11. The apparatus of claim 1 further comprising a host device and an interface circuit coupled to said host device, said interface circuit also coupled to said binary generator. 12. The apparatus of claim 11 wherein said host device is a data system which uses random numbers, said binary generator providing random binary numbers to said host device through said interface circuit. 13. The apparatus of claim 1 wherein said detector comprising a detection device, and an amplifier coupled to said detection device. 14. The apparatus of claim 13 wherein said detection device comprises a silicon semiconductor detector and a detector bias supply circuit. 15. The apparatus of claim 13 wherein said amplifier comprises a charge preamplifier and a linear amplifier coupled to said charge preamplifier. 16. A method for generation of random numbers comprising: randomly producing only alpha decay particles in time from a given source of said alpha particles; selectively detecting at least said alpha decay particles from said given source while avoiding detection of any events other than said alpha decay particles from said given source; generating a detection signal corresponding to positive detection of only said alpha decay particles from said given source; and generating a binary signal in response to positive detection of only said alpha decay particles from said given source which measures successive time intervals between successive positively identified detection signals corresponding to actual detections of said alpha decay particles from said source and which assigns a binary value to said successive time intervals depending on comparative time lengths of said successive time intervals. 17. The method of claim 16 where producing alpha decay particles produces alpha decay particles which have a half-life equal to or longer than 100 years, and which do not produce substantial amounts of alpha-radiation. 18. The method of claim 16 where producing alpha decay particles is performed by providing Am 241 as a source. 19. The method of claim 16 where generating a detection signal corresponding to positive detection of only said alpha decay particles from said given source comprises pattern matching said detection signal to known detection signal profiles of actual alpha decay particles produced by said given source. 20. The method of claim 16 where said detection signal has an output level and where generating a detection signal corresponding to positive detection of only said alpha decay particles from said given source comprises comparing said output level of said detection signal with an output level of a detection signal to known to correspond to actual alpha decay particles.