US3811038A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pseudo-random number generators
Assignee: Fujitsu Services Ltd
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Filing: 1972-09-13
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Granted: 1974-05-14
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Expires: 1992-09-13
Abstract
Abstract A pseudo-random number generator produces a substantially Gaussian distribution of output numbers from a succession of uniform random numbers. In each cycle uniform random numbers are produced and applied to an adder operative to form cumulative sums. A counter is responsive to carry signals from the adder and the outputs of the adder and counter are combined to form an output pseudo-random number. The number of permitted adding operations is preset.
Inventors
- 👤 S Reddaway
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:10
CPC Classifications
G; G06; G06F; G06F7/00; G06F7/58; G06F7/582; G06F7/584; G06F2207/00; G06F2207/58; G06F2207/581; G06F2207/583
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
86 words
A pseudo-random number generator including an adder; means operative to apply a predetermined number of multi-digit uniform random numbers in succession to the adder; an accumulator for storing a cumulative sum; the adder being effective to add each multi-digit random number in turn to the cumulative sum stored in the accumulator to produce a sum signal and carry signal; a counter operative in response to the carry signals to generate output signals; the output signals and the sum signals constituting portions of an output pseudo-random number.
Claim 2
Dependent Claim
86 words
A pseudo-random number generator including an adder; means operative to apply a predetermined number of multi-digit uniform random numbers in succession to the adder; an accumulator for storing a cumulative sum; the adder being effective to add each multi-digit random number in turn to the cumulative sum stored in the accumulator to produce a sum signal and carry signal; a counter operative in response to the carry signals to generate output signals; the output signals and the sum signals constituting portions of an output pseudo-random number.
Claim 3
Dependent Claim
72 words
A generator according to claim 1 wherein the adder includes a plurality of stages and a carry-in terminal, the number of stages being one less than the number of digits in each of said multi-digit uniform random numbers; and said means operative to apply random numbers to the adder includes a line connected to said carry-in terminal for applying the least significant digit of each said uniform random number to the adder.
Claim 4
Dependent Claim
42 words
A generator according to claim 1 wherein said means operative to apply random numbers to the adder includes a plurality of lines, for applying respective digits of each said uniform random number to the adder, one of said lines inCluding an inverter.
Claim 5
Dependent Claim
49 words
A generator according to claim 3 wherein the digital significance of the digit of the uniform random number applied by the line which includes the inverter is equal to the sum of the digital significances of all the other digits of that uniform random number applied to the adder.
Claim 6
Dependent Claim
34 words
A generator according to claim 1 comprising a register for presetting the counter in accordance with the contents of the register to effect offsetting the mean of the resulting distribution of pseudo random numbers.
Claim 7
Dependent Claim
35 words
A generator according to claim 1 wherein said means operative to apply random numbers to the adder includes a further counter presettable to determine the number of said uniform random numbers applied to the adder.
Claim 8
Dependent Claim
65 words
A generator according to claim 1 wherein said means operative to apply random numbers to the adder includes two shift registers each with exclusive -OR feedback from selected stages to their input stages, and a plurality of exclusive-OR gates for combining the contents of pairs of shift register stages, each pair consisting of a stage from each shift register, to form said uniform random numbers.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-13 | 1977-11-12 | 1978-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-13 | 1981-11-12 | 1982-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-13 | 1985-11-12 | 1986-05-14 | $7700.00 | Window Closed / Lapsed |