US3831094A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Means to prevent coincidental phase modulation in an amplitude modulation transmitter
Assignee: Collins Radio Co
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Filing: 1973-08-30
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Granted: 1974-08-20
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Expires: 1993-08-30
Abstract
Abstract Means, including a voltage controlled oscillator in a phaselocked loop, whereby the transmitted carrier frequency is locked to a source of carrier frequency generation. The loop loop includes AM modulator AM modulator such that coincidental phase modulation is removed from AM transmitted AM modulated carrier.
Inventors
- 👤 H Stover
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:52
CPC Classifications
H; H03; H03L; H03L7/00; H03L7/06; H03C; H03C1/00; H03C1/02; H03C1/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
103 words
An amplitude modulation transmitter comprising transmitter frequency generator means providing an output signal the frequency of which defines that of a carrier signal to be transmitted, amplitude modulation means, a voltage controlled oscillator, a modulating input signal, said amplitude modulation means receiving said modulating input signal and the output of said voltage controlled oscillator as respective inputs thereto and developing an amplitude modulated carrier output signal, and means for controlling the phase of the output from said voltage controlled oscillator in accordance with the relative phase between said amplitude modulated carrier output signal and the output signal from said transmitter frequency generator means.
Claim 2
Dependent Claim
103 words
An amplitude modulation transmitter comprising transmitter frequency generator means providing an output signal the frequency of which defines that of a carrier signal to be transmitted, amplitude modulation means, a voltage controlled oscillator, a modulating input signal, said amplitude modulation means receiving said modulating input signal and the output of said voltage controlled oscillator as respective inputs thereto and developing an amplitude modulated carrier output signal, and means for controlling the phase of the output from said voltage controlled oscillator in accordance with the relative phase between said amplitude modulated carrier output signal and the output signal from said transmitter frequency generator means.
Claim 3
Dependent Claim
18 words
An amplitude modulation transmitter as defined in claim 1 wherein said means for controlling comprises a phase-locked loop.
Claim 4
Dependent Claim
88 words
An amplitude modulation transmitter as defined in claim 2 wherein said phase-locked loop comprises a phase detector to which the output of said transmitter frequency generator means and said amplitude modulated output signal are applied as respective first and second inputs, and loop filtering means receiving the output of said phase detector and providing an output control signal for application to said voltage controlled oscillator, whereby said amplitude modulated output signal carrier component is locked in phase quadrature with the output signal from said transmitter frequency generating means.
Claim 5
Dependent Claim
38 words
An amplitude modulation transmitter as defined in claim 3 comprising signal coupling means receiving said amplitude modulated output signal and providing a predetermined low level sample of said output signal as said second input to said phase detector.
References Cited (Backward Citations)
US3509462A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-19 | 1978-02-18 | 1978-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-19 | 1982-02-18 | 1982-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-19 | 1986-02-18 | 1986-08-20 | $7700.00 | Window Closed / Lapsed |