US5012208A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Quadrature modulator having compensation for local oscillator leak
Assignee: Nokia Oyj
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Filing: 1990-04-10
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Granted: 1991-04-30
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Expires: 2010-04-10
Abstract
Abstract The invention relates to a quadrature modulator comprising a circuit for the compensation of a local oscillator leak signal in an output signal of the modulator, which circuit adds different compensation voltages to two modulation signals. To provide an automatic compensation of the local oscillator leak signal, the quadrature modulator of the invention comprises a regulating circuit for the regulation of the intensity of the compensation voltages irrespective of each other on the basis of the correlation between the amplitude variation in the output signal and the corresponding modulation signal.
Inventors
- 👤 Jarmo Makinen
- 👤 Reino Talarmo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:05
CPC Classifications
H; H03; H03C; H03C1/00; H03C1/52
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
67 words
A quadrature modulator comprising means for the compensation of a local oscillator leak signal in an output signal of the modulator, which means add different compensation voltages to two modulation signals, and regulating means for the regulation of the intensity of the compensation voltages irrespective of each other on the basis of a correlation between the amplitude variation in the output signal and the corresponding modulation signal.
Claim 2
Dependent Claim
67 words
A quadrature modulator comprising means for the compensation of a local oscillator leak signal in an output signal of the modulator, which means add different compensation voltages to two modulation signals, and regulating means for the regulation of the intensity of the compensation voltages irrespective of each other on the basis of a correlation between the amplitude variation in the output signal and the corresponding modulation signal.
Claim 3
Dependent Claim
117 words
A quadrature modulator according to claim 1, comprising a detector means connected to the output of the modulator for the production of a feedback signal proportional to the amplitude variations in the output signal, two correlation means, the feedback signal and the first modulation signal being connected to inputs of one correlation means for the production of a first compensation voltage and the feedback signal and the second modulation signal being connected to the inputs of the other correlation means for the production of a second compensation voltage, and first and second adder means for adding the first compensation voltage to the first modulation signal and for adding the second compensation voltage to the second modulation signal.
Claim 4
Dependent Claim
20 words
A quadrature modulator according to claim 2, wherein the compensation voltages are connected to the adder means through integrating means.
Claim 5
Dependent Claim
20 words
A quadrature modulator according to claim 2 or 3, comprising an amplifier before the detector means at the modulator output.
Claim 6
Dependent Claim
33 words
A quadrature modulator according to claim 4, wherein a high pass filter and an amplifier are connected in series between the output of the detector means and the inputs of the correlation means.
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) | 1994-04-29 | 1994-10-29 | 1995-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-04-29 | 1998-10-29 | 1999-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-04-29 | 2002-10-29 | 2003-04-30 | $7700.00 | Window Closed / Lapsed |