US4754259A
Expired / Lapsed
US
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Angle digitizer with enhanced harmonic rejection
Assignee: Honeywell Inc
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Filing: 1987-03-11
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Granted: 1988-06-28
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Expires: 2007-03-11
Abstract
Abstract A device for converting time varying signals which represent sin θ and cos θ of an angle θ, where can take on values over a range, to an n bit digital signal. The range is typically 2π radians and is segmented into 2 n+1 -4 segments. The segments are mapped into 2 n -1 amplitudes, and are encoded as the n bit digital signal. The invention is particularly useful as an angle digitizer where θ represents the phase difference between an input signal and a reference signal. As an angle digitizer, harmonic rejection is enhanced by the efficient use of the n bits to distinguish amplitude states as opposed to distinguishing merely phase states.
Inventors
- 👤 James D. Joseph
- 👤 Dennis D. Ferguson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:02
CPC Classifications
H; H03; H03M; H03M1/00; H03M1/12; H03M1/34
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
136 words
A device for converting time varying electronic singnals which represent sin and cos of an angle θ, where θ can take on values over a range, to an n bit digital signal, said device comprising: means for segmenting said range into 2 n+1 -4 segments in response to said sin θ and said cos θ signals; means for providing, at selected times, a segment digital signal for each of said segments, wherein each of said segment digital signals represent the state of θ in the corresponding one of said segments and wherein the amplitude of each of said segment digital signals is one of 2 n -1 possible amplitudes; and means for encoding said segment digital signals, based on the amplitude of said segment digital signal, as said n bits, to provide said n bit signal.
Claim 2
Independent Claim
136 words
A device for converting time varying electronic singnals which represent sin and cos of an angle θ, where θ can take on values over a range, to an n bit digital signal, said device comprising: means for segmenting said range into 2 n+1 -4 segments in response to said sin θ and said cos θ signals; means for providing, at selected times, a segment digital signal for each of said segments, wherein each of said segment digital signals represent the state of θ in the corresponding one of said segments and wherein the amplitude of each of said segment digital signals is one of 2 n -1 possible amplitudes; and means for encoding said segment digital signals, based on the amplitude of said segment digital signal, as said n bits, to provide said n bit signal.
Claim 3
Dependent Claim
11 words
The device of claim 1 wherein said range is 2π radians.
Claim 4
Dependent Claim
13 words
The device of claim 1 wherein n is either 3, 4 or 5.
Claim 5
Dependent Claim
43 words
The device of claim 1 wherein said means for providing said segment digital signals includes a plurality of comparators wherein pairs of signals are input to each comparator with said inputs each being proportional to said sin θ or to said cos θ.
Claim 6
Dependent Claim
45 words
The device of claim 1 wherein said means for segmenting includes: a plurality of voltage dividers, wherein signals proportional to either sin θ or cos θ are input to said voltage dividers and the outputs from said voltage dividers represent weighted functions of said inputs.
Claim 7
Dependent Claim
40 words
The device of claim 5 wherein there are s of said outputs and s/2 of said outputs are each weighted by a unique kj according to: k.sub.j =tan (π/s+2jπ/s) where s=2.sup.n+1 -4 and j=0, 1, 2 . . . (s/2-1).
Claim 8
Dependent Claim
44 words
The device of claim 6 wherein said means for providing said segment digital signals includes s/2 comparators, wherein a pair of said outputs is applied to each of said comparators, with one of said outputs in each pair being one of said weighted outputs.
Claim 9
Independent Claim
94 words
A method of converting time varying electronic signals which represent sin θ and cos θ of an angle θ, where θ can take on values over a range, to an n bit digital signal, said method comprising: segmenting said range into 2 n+1 -4 segments in response to said sin θ and cos θ signals; mapping, at selected times, each of said segments onto an amplitude state, wherein there are 2 n -1 amplitude states; and encoding said mapped segments, based on the amplitude state of said segments, as said n bit digital signal.
Claim 10
Independent Claim
94 words
A method of converting time varying electronic signals which represent sin θ and cos θ of an angle θ, where θ can take on values over a range, to an n bit digital signal, said method comprising: segmenting said range into 2 n+1 -4 segments in response to said sin θ and cos θ signals; mapping, at selected times, each of said segments onto an amplitude state, wherein there are 2 n -1 amplitude states; and encoding said mapped segments, based on the amplitude state of said segments, as said n bit digital signal.
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) | 1991-06-28 | 1991-12-28 | 1992-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-28 | 1995-12-28 | 1996-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-28 | 1999-12-28 | 2000-06-28 | $7700.00 | Window Closed / Lapsed |