Method and apparatus for generating random numbers
US6480072B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 18, 2000 |
| Grant date | Nov 12, 2002 |
| Priority date | — |
| Expiry date | Apr 18, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F7/588
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A random number generator generates high quality random numbers by sampling the output of a voltage controlled oscillator (VCO) at a frequency much lower than the frequency of the oscillator output. The output frequency of the oscillator is changed significantly during each sampling interval to help ensure the phase relationship of the VCO output and the sampling frequency is unpredictable. That may be accomplished by logically combing the sampling clock and an output from a linear feedback shift register in an exclusive OR gate and supplying that output as the most significant bit used to generate the voltage to control the oscillator. Additional outputs from the linear feedback shift register are also used to generate the control input to the VCO. A distilling circuit such as a CRC circuit or a linear feedback shift register shifts in successive output samples and generates a number therefrom to further increase the randomness of the generated random number.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.