Patent Document ID: 8738675
Application ID: 12375017
Patent Flag: 1

Claim One:
1. A method for generating binary random bits (S (xor)i ) regionally according to distribution based on a non-autonomous, continuous-time chaotic oscillator, comprising the step of: generating non-invertible random binary bits regionally according to distribution of one state which corresponds to a waveform of the continuous-time chaotic oscillator, the generating further comprising steps of: a. determining non-invertible appropriate sections where the distribution of samples has two regions, by considering only the samples belonging to a state x 1 by way of: i. determining appropriate parameters set of normalized quantities, where the samples of the state x from a one dimensional section obtained at a status transition of another state (x 2 , x 3 ,. .. , or x n ) defined as x 2. .. n (t)=x 2. .. n (0) with dx 2. .. n /dt>0 or dx 2. .. n /dt<0, has two regions or, ii. adjusting appropriate x 2. .. n (0) values which corresponds to v 2. .. n (0), where the samples of the state x 1 from the one dimensional section obtained at the status transition of another state (x 2 , x 3 ,. .. , or x n ) defined as x 2. .. n (t)=x 2. .. n (0) with dx 2. .. n /dt>0 or dx 2. .. n /dt<0, has two regions or, iii. determining appropriate parameters set of normalized quantities, where periodic samples of the state x 1 obtained at rising or falling edges of an external periodical pulse signal, that is at times t satisfying ωtmod2π=t o (ω is the frequency of the pulse signal), has two regions or, iv. adjusting appropriate t o , where the periodic samples of the state x 1 obtained at the rising or falling edges of an external periodical pulse signal that is at times t satisfying ωtmod2π=t o (ω is the frequency of the pulse signal), has two regions or, v. determining appropriate parameters set of normalized quantities, where the samples of the states x 1 from the one dimensional section obtained at the rising or falling edges of a periodical pulse signal used to drive the non-autonomous chaotic oscillator (at times t satisfying ωtmod2π=t o where ω is the frequency of the pulse signal and 0<t o <1 has two regions or, vi. adjusting appropriate t o , where samples of the states x 1 from the one dimensional section obtained at the rising or falling edges of a periodical pulse signal used to drive the non-autonomous chaotic oscillator (at times t satisfying ωtmod2π=t o where ω is the frequency of the pulse signal and 0<t o <1) has two regions; b. generating binary S (top)i and S (bottom)i from regional x 1i values obtained from the appropriate section defined in step a above for regional thresholds according to the following equation: 
 S (top)i =sgn ( x 1i −q top ) when x 1i ≧q middle 
 S (bottom)i =sgn ( x 1i −q bottom ) when x 1i <q middle where sgn(.) is the signum function, q top and q bottom are the thresholds for top and bottom distributions respectively and wherein q top and q bottom are chosen as thresholds because they are determined to be the medians of the top and bottom distributions, and q middle is the boundary between the distributions; c. realizing offset compensations for q top and q bottom thresholds defined in step b above by implementing a Monobit Test; d. realizing frequency compensation for the sampling frequency of x 1 by implementing a Runs Test to avoid oversampling of x 1 ; e. generating random binary data S (xor)i using the binary sequences S (top)i and S (bottom)i defined in step b above according to the following equation: 
 S (xor)i =S (top)i (XOR) S (bottom)i where exclusive-or (XOR) operation is exploited to eliminate the bias in order not to decrease the throughput.