JP2001117757A - Probability generator and random number generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate a correct probability value even when the average number of pulses per unit time is changed in a probability generator utilizing the random generation of radiant rays from a radioactive substance or white noise from a diode. SOLUTION: A memory 9 sequentially stores the average number of pulses per unit time measured by a measuring circuit 3. A clock correction circuit 6 changes the clock period of a clock pulse generator 11 so as to cancel the increment/decrement of the average number of pulses when the average number is changed. Consequently the same probability value is obtained even when the average number of pulses per unit time in a random pulse source 10 is changed. A pulse evaluation circuit 7 defines plural sections by dividing a time interval and judges whether the number of pulses included in each section is based on prescribed exponential distribution or not. Consequently whether pulses are generated from the random pulse source 10 always at random or not, i.e., whether an appropriate probability value is obtained or not, can be easily judged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probability generator and a random number generator manufactured by utilizing the fact that radiation of radioactive materials and white noise of a diode are randomly generated.

[0002]

2. Description of the Related Art Conventionally, as a probability generator of this type, as disclosed in Japanese Patent No. 2880636, for example, radiation or white noise randomly emitted from a radioactive substance or a diode is pulsed to reduce the number of pulses. One that counts and generates a probability value based on the number of pulses is known.

[0003] Some probability generators using radioactive materials have increased security by preventing human tampering. The method measures the total number of pulses over a certain period of time,
The deviation of the total number of pulses from a normal average value is determined to determine whether or not an illegal operation has been performed.

[0004]

However, this has the following disadvantages.

First, the pulse frequency of a random pulse source may change due to a change in its properties (deterioration), a change in its structure, or an unauthorized operation by a third party. May continue to be generated.

For example, when a diode is used as a random pulse source, the white noise from the diode has a temperature dependency, so that if there is a difference in temperature, the average number of pulses per unit time also changes. Then, when the average number of pulses per unit time deviates from the already set value, the probability generator generates an erroneous probability value.

In a probability generator using a radioactive substance, the average number of pulses per unit time used in calculating a probability value is measured before shipment, and the value is continuously used. Radiation exponentially decreases with time, and the average number of pulses per unit time decreases accordingly, so that the probability value deviates from the factory setting. If the deviation of the probability values cannot be ignored, the probability generator must be discarded, and the life of the probability generator is shortened.

Second, the fraud detection method cannot detect fraud unless the total number of pulses for a certain period of time deviates from a normal average value. If it is designed so that it can send a proper pulse, fraud detection becomes impossible.

[0009] The same applies to the random number generator as well as the probability generator.

[0010] In view of such circumstances, the present invention can avoid various inconveniences due to a change in the pulse frequency of a random pulse source, and can detect the presence or absence of fraud to apply an artificial pulse. It is an object of the present invention to provide a probability generator and a random number generator capable of performing the following.

[0011]

That is, the invention relating to the probability generator of the present invention comprises a random pulse source (10) for emitting a random pulse, and a predetermined clock period (τ).
Clock pulse generator (1)
And 1) counting the total number of random pulses emitted from the random pulse source based on the clock pulse sent from the clock pulse generator at regular intervals, and calculating the average number of pulses per unit time ( Probability generating means provided with measuring means (2, 3) for calculating n) and probability generating means (5) for generating a probability value (P) based on the average number of pulses per unit time calculated by the measuring means. In the device (1), a memory (9) for sequentially storing the average number of pulses per unit time calculated by the measuring means is provided, and when the average number of pulses per unit time stored in this memory increases or decreases, Clock correction means (6) for changing the clock cycle of the clock pulse generator so as to cancel the increase / decrease is provided. By employing such a configuration, a correct probability value can be obtained even if the average number of pulses per unit time of the random pulse source changes.

Further, a pulse evaluation means (7) for determining a plurality of sections by dividing the time interval (t) and determining whether or not the number of pulses (S) included in each section follows a predetermined exponential distribution. Is provided. With such a configuration, it is possible to easily determine whether or not the pulse from the random pulse source (10) is always random. Therefore, it is possible to determine whether or not the pulse has a reasonable probability value (P), and it is also possible to determine whether the pulse has a random artificial value. If there is an irregularity that can cause a pulse, it can be detected.

On the other hand, among the present invention, the invention relating to the random number generator is characterized in that a random pulse source (1) for emitting a random pulse is provided.
0), and a clock pulse generator (11) for emitting a clock pulse at a predetermined clock period (τ). The clock pulse generator (11) emits a clock pulse from the random pulse source based on the clock pulse sent from the clock pulse generator. Measuring means (2, 2) for calculating the average number of pulses (n) per unit time by counting the total number of random pulses at predetermined time intervals.
In a random number generator provided with 3) and provided with random number generating means for generating a random number based on the average number of pulses per unit time calculated by the measuring means, the average number of pulses per unit time calculated by the measuring means is A clock correcting means (9) for sequentially storing a clock (9) for changing the clock cycle of the clock pulse generator so as to cancel the increase or decrease when the average number of pulses per unit time stored in the memory increases or decreases. 6) is provided. By adopting such a configuration, a correct random number can be obtained even if the average number of pulses per unit time of the random pulse source changes.

Further, a pulse evaluation means (7) for determining a plurality of sections by dividing the time interval (t) and determining whether the number of pulses (S) included in each section follows a predetermined exponential distribution. Is provided. With such a configuration, it is possible to easily determine whether or not the pulse from the random pulse source (10) is always random. Therefore, it is possible to determine whether or not the pulse is an appropriate random number, and to apply a non-random artificial pulse. If such fraud is found, it can be detected.

It should be noted that reference numerals in parentheses are for convenience of representing corresponding elements in the drawings, and therefore, the present invention is not limited to the description on the drawings. The same applies to the column of “Claims”.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a control block diagram showing an embodiment of a probability generator according to the present invention, FIG. 2 is a schematic diagram showing a probability generation process when a radioactive substance is used as a random pulse source, and FIG. FIG. 4 is a schematic diagram illustrating a probability generation process when a diode is used as a source, FIG. 4 is a schematic diagram illustrating a first method of dividing a time interval, FIG. 5 is a schematic diagram illustrating a second method of dividing a time interval, and FIG. FIG. 6 is a schematic diagram showing a third method of dividing a time interval.

As shown in FIG. 1, the probability generator 1
The main control circuit 2 includes a measurement circuit 3, a probability generation circuit 5, a clock correction circuit 6, a pulse evaluation circuit 7, and a memory 9. Further, a random pulse source 10 and a clock pulse generator 11 are connected to the measuring circuit 3. Here, the random pulse source 10 emits a random pulse, and the distribution of the time interval from the generation of a certain pulse to the generation of the next pulse is an exponential distribution, and specifically, a radioactive substance that emits radiation. And a diode that emits white noise.

Therefore, the probability generator 1 employing a radioactive material as the random pulse source 10 utilizes the radiation randomly emitted from the radioactive material as shown in FIG. Generate.

First, the main control circuit 2 instructs the measuring circuit 3 to count pulses, and the measuring circuit 3
, The total number of random pulses emitted from the radioactive material is counted at regular intervals based on the clock pulses successively transmitted from. Then, the main control circuit 2 calculates the average number of pulses n per unit time, sequentially writes the total number of pulses and the average number of pulses n into the memory 9, and outputs the average number of pulses n to the clock correction circuit 6. In response, the clock correction circuit 6 determines whether or not the clock correction of the clock pulse generator 11 is necessary. If necessary, the clock correction circuit 6 executes the correction. To generate a probability value.

That is, the average number n of pulses emitted per unit time from a radioactive substance, the time interval t from the emission of a certain pulse to the emission of the next pulse, and the emission of pulses at the time interval t The relational expression shown in Equation 1 holds between the number of pulses N and the time interval t of the pulses.
Takes the value (t1 ≦ t ≦ t2) that is equal to or more than t1 and equal to or less than t2 (t1 ≦ t ≦ t2). Therefore, by specifying these t1 and t2, the probability value P can be set. It can be carried out. Note that in the equations shown in Equations 1 and 2, ex
p represents a power of the base e of the natural logarithm.

N = A exp (−nt) (where A is a constant independent of t)

P = exp (-nt1) -exp (-nt2)

At this time, as is apparent from Equation 2, since the probability value P depends on the average number of pulses n per unit time, the average number of pulses n per unit time is read from the memory 9 and It is determined whether or not the average number of pulses n has changed. If the average number of pulses n per unit time has changed, the time interval t is changed to the clock period τ in order to execute the clock correction of the clock pulse generator 11. The clock period τ is converted in inverse proportion to the average number of pulses n per unit time, based on the fact that it can be expressed by the product of the number of clocks ε (t = τε). That is, when the average pulse number n per unit time changes to n ′, the clock cycle τ is converted to τ ′ = (n / n ′) τ. Then, even if the average number of pulses n per unit time (therefore, the pulse frequency) changes, the same probability value P is maintained without changing the number of clocks ε.
Can be obtained. Of course, when the average number of pulses n per unit time does not change, there is no need to perform clock correction of the clock pulse generator 11.

On the other hand, the pulse evaluation circuit 7 determines whether or not the probability value thus generated is appropriate. To do this, as shown in FIGS. 4 and 5, a time interval t is appropriately divided to determine a plurality of sections, and the number of pulses S included in each section is calculated using a probability density function. Determine whether the value matches. As a result, if both match, the probability value is determined to be valid. Conversely, if both do not match, the probability value is determined to be invalid. The time interval t can be divided in various ways. For example, as shown in FIG. 4, the time interval t may be divided so that the expected number of pulses S in each section becomes uniform. , The time interval t may be equally divided. At this time, in the section where the time interval t is small, the counting of the pulses is apt to occur, and the pulse coming at the large time interval t exceeding the measurement time cannot be measured. Since the measured values are smaller, as shown in FIG.
It is preferable that the determination is made by deleting the hatched portion in FIG.

The probability generator 1 employing a radioactive material as the random pulse source 10 has been described above.
As shown in (1), it is also possible to employ a diode as the random pulse source 10 and configure a similar probability generator using the white noise of this diode.

Although the probability generator 1 has been described in the above-described embodiment, the present invention is modified by adopting a random number generation circuit for generating a random number instead of the probability generation circuit 5 for generating the probability value P. It can also be applied to a generator (not shown).

[0026]

As described above, according to the probability generator of the present invention, the random pulse source 10 for emitting a random pulse and the clock pulse for emitting a clock pulse at a predetermined clock period τ are provided. An average pulse per unit time by counting the total number of random pulses emitted from the random pulse source 10 based on a clock pulse transmitted from the clock pulse generator 11 at regular intervals. A measuring means (main control circuit 2, measuring circuit 3, etc.) for calculating the number n is provided, and a probability generating means (probability generating means) for generating a probability value P based on the average number of pulses per unit time n calculated by the measuring means. In the probability generator 1 provided with the circuit 5), the memory 9 for sequentially storing the average number n of pulses per unit time calculated by the measuring means is provided. When the average number of pulses n per unit time stored in the memory 9 increases or decreases, the clock correction means (clock correction circuit 6) changes the clock period τ of the clock pulse generator 11 so as to cancel the increase or decrease. ), The same probability value P can be obtained even if the average number of pulses per unit time n of the random pulse source 10 changes. Can be provided.

Further, a pulse evaluation means (such as a pulse evaluation circuit 7) for determining a plurality of sections by dividing the time interval t and determining whether or not the number S of pulses included in each section follows a predetermined exponential distribution. Is provided, it is possible to easily determine whether or not the pulse from the random pulse source 10 is always random, and thus it is possible to determine whether or not the pulse has an appropriate probability value P. In the case where there is a fraud that can be applied, a highly reliable probability generator 1 that can detect the presence or absence of a fraud that can be applied with an artificial pulse can be detected. Can be provided.

On the other hand, according to the invention relating to the random number generator of the present invention, there is provided a random pulse source 10 for emitting a random pulse and a clock pulse generator 11 for emitting a clock pulse at a predetermined clock period τ. A measurement of counting the total number of random pulses emitted from the random pulse source 10 based on the clock pulse transmitted from the clock pulse generator 11 at regular intervals, and calculating the average number n of pulses per unit time. Means (main control circuit 2, measuring circuit 3, etc.) and random number generating means (random number generating circuit, etc.) for generating random numbers based on the average number of pulses per unit time n calculated by the measuring means. A memory 9 for sequentially storing the average number n of pulses per unit time calculated by the measuring means. When the average number of pulses n per unit time increases or decreases, clock correction means (clock correction circuit 6 or the like) for changing the clock cycle τ of the clock pulse generator 11 is provided so as to cancel the increase or decrease. Therefore, even if the average number of pulses n per unit time of the random pulse source 10 changes, a correct random number can be obtained, so that various inconveniences caused by a change in the pulse frequency of the random pulse source 10 can be avoided. A random number generator can be provided.

Further, a pulse evaluation means (such as a pulse evaluation circuit 7) for determining a plurality of sections by dividing the time interval t and determining whether the number S of pulses included in each section follows a predetermined exponential distribution. , It is possible to easily determine whether or not the pulse from the random pulse source 10 is always random. Therefore, it is possible to determine whether or not the pulse is an appropriate random number, and to apply a non-random artificial pulse. Provide a highly reliable random number generator that can detect the presence or absence of fraud that can be applied with artificial pulses because it can detect such fraud. Can be.

[Brief description of the drawings]

FIG. 1 is a control block diagram showing one embodiment of a probability generator according to the present invention.

FIG. 2 is a schematic diagram showing a probability generation process when a radioactive substance is used as a random pulse source.

FIG. 3 is a schematic diagram showing a probability generation process when a diode is used as a random pulse source.

FIG. 4 is a schematic diagram showing a first method of dividing a time interval.

FIG. 5 is a schematic diagram showing a second method of dividing a time interval.

FIG. 6 is a schematic diagram showing a third method of dividing a time interval.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Probability generator 2 ... Measurement means (main control circuit) 3 ... Measurement means (measurement circuit) 5 ... Probability generation means (probability generation circuit) 6 ... Clock correction means (clock correction circuit) 7 ... Pulse evaluation means (pulse evaluation circuit) 9 Memory 10 Random pulse source 11 Clock pulse generator n Average pulse number per unit time P Probability value S Number of pulses in each section t …… Time interval ε… Number of clocks τ …… Clock period

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // G06F 101: 14 H04L 9/00 655 (72) Inventor Takakuni Shimizu 5-36 Shimbashi, Minato-ku, Tokyo No. 11 Iwaki Electronics Co., Ltd. F-term (reference) 5B079 BA01 BC10 5J104 FA10 GA01 NA04

Claims (4)

[Claims] 1. A clock signal generator comprising: a random pulse source (10) for emitting a random pulse; and a clock pulse generator (11) for emitting a clock pulse at a predetermined clock cycle (τ). Measuring means (2, 3) for calculating the average number of pulses per unit time (n) by counting the total number of random pulses emitted from the random pulse source at regular intervals based on the clock pulse to be generated; A probability generating means (5) for generating a probability value (P) based on the average number of pulses per unit time calculated by the measuring means;
In the probability generator (1), a memory (9) for sequentially storing the average number of pulses per unit time calculated by the measuring means is provided, and the average number of pulses per unit time stored in the memory increases or decreases. A probability generator characterized by comprising clock correction means (6) for changing the clock cycle of the clock pulse generator so as to cancel the increase / decrease of the increase / decrease. 2. A pulse evaluation means for determining a plurality of sections by dividing a time interval (t) and determining whether the number of pulses (S) included in each section follows a predetermined exponential distribution. The probability generator according to claim 1, further comprising: And a clock pulse generator (11) for emitting a clock pulse at a predetermined clock period (τ). The clock pulse generator sends out the clock pulse from the clock pulse generator. Measuring means (2, 3) for calculating the average number of pulses per unit time (n) by counting the total number of random pulses emitted from the random pulse source at regular intervals based on the clock pulse to be generated; A random number generator provided with random number generating means for generating a random number based on the average number of pulses per unit time calculated by the measuring means, a memory for sequentially storing the average number of pulses per unit time calculated by the measuring means; (9) is provided so that when the average number of pulses per unit time stored in the memory increases or decreases, the increase or decrease cancels the increase or decrease. A random number generator provided with clock correction means (6) for changing a clock cycle of a lock pulse generator. 4. A pulse evaluation means (7) for dividing a time interval (t) to determine a plurality of sections and determining whether the number of pulses (S) included in each section follows a predetermined exponential distribution. The random number generator according to claim 3, further comprising: