US4298942A
Expired / Lapsed
US
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Nonlinear amplitude detector
Assignee: United States Department of the Air Force
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Filing: 1979-12-19
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Granted: 1981-11-03
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Expires: 1999-12-19
Abstract
Abstract A nonlinear amplitude detector generates signal amplitude from the signal's inphase and quadrature components based on a Binomial series expansion. The amplitude detector significantly reduces the processing requirement from an ideal square root operation and yet provides much improved error performance over a conventionally used linear amplitude detector. In operation, the inphase and quadrature signal components are compared for relative magnitude and the smaller magnitude signal component is squared and divided by the large magnitude signal component. The quotient from this operation is multiplied by a coefficient that is selected to provide desired amplitude error deviation characteristics. Signal amplitude is then determined by summing this product with the larger magnitude signal component.
Inventors
- 👤 Henry E. Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:17
CPC Classifications
G; G06; G06F; G06F17/00; G06F17/10
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
74 words
A nonlinear amplitude detector comprising comparator means receiving the inphase and quadrature components of a signal and determining the relative magnitude thereof, signal component squaring means squaring the smaller magnitude signal component, means for dividing the squared smaller magnitude signal component by the larger magnitude signal component, first multiplier means multiplying the quotient thereof by a coefficient α, and means for summing the output of said multiplier means with the larger magnitude signal component.
Claim 2
Dependent Claim
74 words
A nonlinear amplitude detector comprising comparator means receiving the inphase and quadrature components of a signal and determining the relative magnitude thereof, signal component squaring means squaring the smaller magnitude signal component, means for dividing the squared smaller magnitude signal component by the larger magnitude signal component, first multiplier means multiplying the quotient thereof by a coefficient α, and means for summing the output of said multiplier means with the larger magnitude signal component.
Claim 3
Dependent Claim
80 words
A nonlinear amplitude detector as defined in claim 1 wherein said means for dividing the squared smaller magnitude signal component by the larger magnitude signal component comprises a a second multiplier means and an inverse function look-up table, said inverse function look-up table being accessed by and having an output responsive to the larger magnitude signal component, said second multiplier means receiving the outputs of said signal component squaring means and said look-up table and feeding said first multiplier means.
Claim 4
Dependent Claim
24 words
A nonlinear amplitude detector as defined in claim 2 wherein said coefficient α is a value selected from a range between 0.35 and 0.50.
Claim 5
Dependent Claim
25 words
A nonlinear amplitude detector as defined in claim 3 including a third multiplier means multiplying the output of said summing means by a constant k.
Claim 6
Dependent Claim
15 words
A nonlinear amplitude detector as defined in claim 4 wherein said constant k is unity.
Claim 7
Dependent Claim
15 words
A nonlinear amplitude detector as defined in claim 2 wherein said coefficient α is 0.449.
Claim 8
Dependent Claim
15 words
A nonlinear amplitude detector as defined in claim 2 wherein said coefficient α is 0.428.
Claim 9
Dependent Claim
15 words
A nonlinear amplitude detector as defined in claim 2 wherein said coefficient α is 0.430.
References Cited (Backward Citations)
US3281846A
Cited
US3699463A
Cited
US3757214A
Cited
US3761829A
Cited
US3792364A
Cited
US3838350A
Cited
US3829671A
Cited
US3858036A
Cited
US4079329A
Cited
US4173017A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-02 | 1985-05-04 | 1985-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-02 | 1989-05-04 | 1989-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-02 | 1993-05-04 | 1993-11-03 | $7700.00 | Window Closed / Lapsed |