US3628154A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low distortion signal band shifting with on-off switches
Assignee: Individual
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Filing: 1968-05-31
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Granted: 1971-12-14
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Expires: 1988-05-31
Abstract
Abstract Simple switches are used for shifting a signal band, fo, to a new location, fo+f1, without distortion. The band is split into two opposed phases, chopped with square waves of frequencies f1 and odd harmonies 3f1, 5f1, etc., which are weighted in amplitude by the factors 1, one-third, one-fifth, etc., and are finally added. Unwanted components 3f1, 5f1, etc., are found to be easily canceled, obviating a difficult filtering problem.
Inventors
- 👤 Lawrence R Weill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:20
CPC Classifications
H; H03; H03D; H03D7/00; H03D2200/00; H03D2200/0001; H03D2200/0021; H03D2200/0025; H03D2200/0027; H03D2200/0041; H03D2200/006
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
155 words
The method of shifting a band of frequencies, having a center frequency fo, from fo to a new wanted spectrum centered at fo + OR - f1, said method comprising the steps of; splitting the phase of said band to produce two phase-opposed replicas of said band in separate circuits, locAlly simultaneously generating harmonically related phase coherent square waves of frequencies f1 and nf1, where n is an odd integral number, alternately feeding said phase-opposed replicas to an output circuit at said frequency f1 to produce modulation products f1 + OR - fo, alternately feeding said phase-opposed replicas to said output circuit at said frequency nf1, to produce modulation products nf1 + OR - fo, weighting the amplitudes of the two modulation products, respectively, by factors of 1 and 1/n, and adding together the weighted signals so that unwanted higherorder spectral components of the mentioned modulation products which overlap the wanted output spectrum are canceled.
Claim 2
Independent Claim
155 words
The method of shifting a band of frequencies, having a center frequency fo, from fo to a new wanted spectrum centered at fo + OR - f1, said method comprising the steps of; splitting the phase of said band to produce two phase-opposed replicas of said band in separate circuits, locAlly simultaneously generating harmonically related phase coherent square waves of frequencies f1 and nf1, where n is an odd integral number, alternately feeding said phase-opposed replicas to an output circuit at said frequency f1 to produce modulation products f1 + OR - fo, alternately feeding said phase-opposed replicas to said output circuit at said frequency nf1, to produce modulation products nf1 + OR - fo, weighting the amplitudes of the two modulation products, respectively, by factors of 1 and 1/n, and adding together the weighted signals so that unwanted higherorder spectral components of the mentioned modulation products which overlap the wanted output spectrum are canceled.
Claim 3
Independent Claim
173 words
A system for shifting a predetermined amount a band of signals having the center frequency, fo, to a new wanted band centered at fo + or - f1 said system comprising; means for locally simultaneously generating a wave containing frequency f1 and a predetermined integral multiple, nf1, thereof, where n is any odd whole number, phase-splitting means for simultaneously producing in separate circuits opposed phases of said band of signal frequencies, an output circuit, means connected to the mentioned local generating means and responsive to said frequency f1 for alternately connecting said opposed phases from said separate circuits to said output circuit at frequency f1, means connected to the mentioned local generating means and responsive to said frequency nf1 for alternately connecting said opposed phases from said separate circuits to said output circuit at frequency nf1, and means for weighting the f1-connected and the nf1-connected phases by factors, respectively, of 1 and 1/n, and for algebraically adding the weighted signals so that unwanted multiplication products appearing in the wanted output band are cancelled.
Claim 4
Independent Claim
173 words
A system for shifting a predetermined amount a band of signals having the center frequency, fo, to a new wanted band centered at fo + or - f1 said system comprising; means for locally simultaneously generating a wave containing frequency f1 and a predetermined integral multiple, nf1, thereof, where n is any odd whole number, phase-splitting means for simultaneously producing in separate circuits opposed phases of said band of signal frequencies, an output circuit, means connected to the mentioned local generating means and responsive to said frequency f1 for alternately connecting said opposed phases from said separate circuits to said output circuit at frequency f1, means connected to the mentioned local generating means and responsive to said frequency nf1 for alternately connecting said opposed phases from said separate circuits to said output circuit at frequency nf1, and means for weighting the f1-connected and the nf1-connected phases by factors, respectively, of 1 and 1/n, and for algebraically adding the weighted signals so that unwanted multiplication products appearing in the wanted output band are cancelled.
Claim 5
Dependent Claim
35 words
In the system defined in claim 2; means for generating a plurality of odd-numbered integral multiples of frequency f1, and means responsive to each multiple for alternately switching said opposed phases to said output circuit.
Claim 6
Dependent Claim
27 words
In the system defined in claim 3; means for attenuating each switched signal to an amplitude of 1/n, where n is the number of said odd-numbered multiple.
Claim 7
Dependent Claim
28 words
In the system defined in claim 2, said local generating means comprising; an oscillator for frequency f1, and a multiplier for simultaneously generating a plurality of odd-numbered multiples.
Claim 8
Dependent Claim
47 words
In the system defined in claim 2, said phase-splitting means comprising; two amplifiers with inputs connected in parallel to said source of signals, and outputs connected, respectively, to said separate circuits, and said amplifiers having gains, respectively, of +1 and -1 to produce said opposed phase signals.
Claim 9
Dependent Claim
43 words
In the system defined in claim 2, said adding means comprising; an operational amplifier having an apparent infinite input impedance, and resistors connected between the amplifier input and, respectively, f1-connecting and the nf1-connecting means, said resistors having, substantially, values of R and nR.
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) | 1974-12-13 | 1975-06-14 | 1975-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-13 | 1979-06-14 | 1979-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-13 | 1983-06-14 | 1983-12-14 | $7700.00 | Window Closed / Lapsed |