US3746891A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digitally controlled sine wave generator
Assignee: LINK TACTICAL MILITARY SIMULATION Corp EXISTING UNDER LAWS OF DELAWARE
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Filing: 1971-12-27
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Granted: 1973-07-17
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Expires: 1991-12-27
Abstract
Abstract Shown is a sine wave generator provide a highly stable output frequency which may be selected by an input signal from a digital computer. A crystal controlled oscillator provides its output to a digital counter, the output of which is compared with a register loaded by the computer. Each time the count equals the loaded value a flipflop is triggered and the counter reset causing the flipflop to provide a square wave output of a predetermined frequency. The square wave is then filtered by a digitally controlled filter to provide a final output which is a sine wave of the desired frequency.
Inventors
- 👤 J Rowe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:52
CPC Classifications
H; H03; H03B; H03B21/00; H03B21/01; H03B21/02; H03B21/025
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
158 words
A stable sine wave generator comprising a stable accurate source of clock pulses, a counter, means for connecting the outupt of said source to the count input of said counter to cause said counter to count said clock pulses, a register, means for inserting into said register values representative of the period of the sine wave to be generated, a comparator, means for applying the contents of the register to one input of said comparator and for applying the changing contents of the counter to another input of said comparator, said comparator generating an output signal when it detects coincidence between its two inputs, a triggered square wave generator connected to the output from said comparator and responding to said signal as a trigger to generate a full square wave in response thereto, and means connected to the output of said square wave generator for converting said full square wave into a sine wave of the same frequency.
Claim 2
Dependent Claim
158 words
A stable sine wave generator comprising a stable accurate source of clock pulses, a counter, means for connecting the outupt of said source to the count input of said counter to cause said counter to count said clock pulses, a register, means for inserting into said register values representative of the period of the sine wave to be generated, a comparator, means for applying the contents of the register to one input of said comparator and for applying the changing contents of the counter to another input of said comparator, said comparator generating an output signal when it detects coincidence between its two inputs, a triggered square wave generator connected to the output from said comparator and responding to said signal as a trigger to generate a full square wave in response thereto, and means connected to the output of said square wave generator for converting said full square wave into a sine wave of the same frequency.
Claim 3
Dependent Claim
17 words
The invention according to claim 1 wherein said counter, said register and said comparator are binary devices.
Claim 4
Dependent Claim
13 words
The invention according to claim 2 wherein said binary devices comprise micro circuits.
Claim 5
Dependent Claim
20 words
The invention according to claim 2 wherein said means to insert values comprises a plurality of switches assigned binary values.
Claim 6
Dependent Claim
16 words
The invention according to claim 2 wherein said means to insert values comprises a digital computer.
Claim 7
Dependent Claim
15 words
The invention according to claim 1 wherein said square wave generator is a flip-flop. Pg,6
Claim 8
Dependent Claim
67 words
The invention according to claim 1 wherein said means for converting comprises a digitally controlled filter connected to the output of said square wave generator and wherein said means to insert values further includes means to provide a binary signal to control said filter whereby the square wave output of said square wave generator after passing through said filter will be converted to substantially a sine wave.
Claim 9
Dependent Claim
15 words
The invention according to claim 7 wherein said oscillator is a crystal controlled oscillator source.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-16 | 1977-01-15 | 1977-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-16 | 1981-01-15 | 1981-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-16 | 1985-01-15 | 1985-07-17 | $7700.00 | Window Closed / Lapsed |