Patent US4855944A successfully refreshed from Google Patents.
US4855944A
Expired / Lapsed
US
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Noise generator with shaped spectrum
Assignee: Boeing North American Inc
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Filing: 1987-09-04
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Granted: 1989-08-08
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Expires: 2007-09-04
Abstract
Abstract Pseudorandom noise having a predetermined frequency spectrum is generated by implementing a finite impulse response filter as an integral part of a feedback shift register sequence generator.
Inventors
- 👤 Billy D. Hart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:47
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/84
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
54 words
A pseudorandom noise generator, comprising: a feedback shift register sequence generator, having a multiplicity of stages, each presenting an interstage signal; means for multiplying at least one of said interstage signals by a predetermined factor; and means for summing signals produced by said multiplying means to produce pseudorandom noise having a desired frequency spectrum.
Claim 2
Dependent Claim
54 words
A pseudorandom noise generator, comprising: a feedback shift register sequence generator, having a multiplicity of stages, each presenting an interstage signal; means for multiplying at least one of said interstage signals by a predetermined factor; and means for summing signals produced by said multiplying means to produce pseudorandom noise having a desired frequency spectrum.
Claim 3
Dependent Claim
23 words
A pseudorandom noise generator as described in claim 1 wherein said multiplying means comprises a resistor for receiving each of said interstage signals.
Claim 4
Dependent Claim
27 words
A pseudorandom noise generator as described in claim 2 wherein said multiplying means further comprises an inverter to receive each of selected ones of said interstage signals.
Claim 5
Dependent Claim
47 words
A pseudorandum noise generator, comprising: A FIR filter having a multiplicity of stages 1 . . . n, each of said stages having an input and an output; and An EXCLUSIVE-OR gate for applying output signals from at least one of said stages to the 1st stage.
Claim 6
Dependent Claim
47 words
A pseudorandum noise generator, comprising: A FIR filter having a multiplicity of stages 1 . . . n, each of said stages having an input and an output; and An EXCLUSIVE-OR gate for applying output signals from at least one of said stages to the 1st stage.
Claim 7
Dependent Claim
25 words
A pseudorandom noise generator as described in claim 4 wherein said EXCLUSIVE-OR gate applies an output signal from the n-th stage of the FIR filter.
Claim 8
Dependent Claim
31 words
A pseudorandom noise generator as described in claim 5 wherein said EXCLUSIVE-OR gate further applies an output signal from at least one stage of the FIR filter below the n-th stage.
Claim 9
Dependent Claim
21 words
A pseudorandom noise generator as described in claim 6 wherein said one stage below the n-th stage is the 1st stage.
Claim 10
Dependent Claim
70 words
A pseudorandom noise generator, comprising: a shift register comprising a multiplicity of stages; feedback means for applying the output from at least one of said stages to the first stage thereof; means for deriving signals from at least one of the stages; means for multiplying each of said derived signals by a predetermined factor; and means for summing said multiplied signals to produce pseudorandom noise having a desired frequency spectrum.
Claim 11
Dependent Claim
70 words
A pseudorandom noise generator, comprising: a shift register comprising a multiplicity of stages; feedback means for applying the output from at least one of said stages to the first stage thereof; means for deriving signals from at least one of the stages; means for multiplying each of said derived signals by a predetermined factor; and means for summing said multiplied signals to produce pseudorandom noise having a desired frequency spectrum.
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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) | 1992-08-07 | 1993-02-06 | 1993-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-07 | 1997-02-06 | 1997-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-07 | 2001-02-06 | 2001-08-08 | $7700.00 | Window Closed / Lapsed |