US4721924A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for tuning a VCO to the carrier frequency of each radar pulse
Assignee: Leonardo SpA
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Filing: 1985-07-03
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Granted: 1988-01-26
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Expires: 2005-07-03
Abstract
Abstract An electronic device for rapidly tuning a voltage controlled oscillator to the radar carrier frequency of each of the individual radar pulses. A frequency discriminator (1) of the quadricorrelator type is supplied with the incoming pulses and with the output of the VCO (5) to provide the control voltage to the VCO (5) via amplifying stages (2), (4) and a sample-and-hold circuit (3) that maintains the tuned frequency for time durations greater than 100 usec. The operating frequency range of the device is between 6GHz-18GHz.
Inventors
- 👤 Arturo Masdea
- 👤 Pietro Bartolini
- 👤 Gianfranco Colavito
- 👤 Filippo Neri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:39
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/28; H; H03; H03L; H03L7/00; H03L7/06; H03L7/08; H03L7/085; H03L7/087; H03L7/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
107 words
A device for rapidly tuning the frequency of a voltage controlled oscillator to the carrier frequency of each pulse of a radar, comprising: a frequency discriminator having two inputs and adapted to receive radar pulses directly to one of the two inputs; a first amplifier coupled to the output of the frequency discriminator; a sample-and-hold circuit coupled to the output of the first amplifier; a second amplifier coupled to the output of the sample-and-hold circuit; and a voltage controlled oscillator coupled to the output of the second amplifier, the output of which voltage controlled oscillator is in turn coupled to the second input of the frequency discriminator.
Claim 2
Independent Claim
107 words
A device for rapidly tuning the frequency of a voltage controlled oscillator to the carrier frequency of each pulse of a radar, comprising: a frequency discriminator having two inputs and adapted to receive radar pulses directly to one of the two inputs; a first amplifier coupled to the output of the frequency discriminator; a sample-and-hold circuit coupled to the output of the first amplifier; a second amplifier coupled to the output of the sample-and-hold circuit; and a voltage controlled oscillator coupled to the output of the second amplifier, the output of which voltage controlled oscillator is in turn coupled to the second input of the frequency discriminator.
Claim 3
Dependent Claim
93 words
The device of claim 1 in which the frequency discriminator is comprised of at least two input mixers, a 90° hybrid coupled to one input of each of the input mixers, a differentiator coupled to the output of one of the mixers, at least two amplifiers, and an output mixer, such that a direct current term is generated at the output of the output mixer which is proportional to the difference frequency in sign and to a frequency term which is twice the frequency difference and varies as the cosine of the input.
Claim 4
Dependent Claim
19 words
The device of claim 2 in which the frequency discriminator operates as a quadricorrelator in an R.F. tuning loop.
Claim 5
Dependent Claim
12 words
The device of claim 3 having an operating frequency range of 6GHZ-18GHz.
Claim 6
Dependent Claim
22 words
The device of claim 4 which maintains the tuned frequency of the voltage controlled oscillator for time durations greater than 100 microseconds.
References Cited (Backward Citations)
FR1257554A
Cited
US3794771A
Cited
US4061979A
Cited
US4101844A
Cited
WO1981001616A1
Cited
US4651104A
Cited
US4600889A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-01-25 | 1991-07-27 | 1992-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-25 | 1995-07-27 | 1996-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-25 | 1999-07-27 | 2000-01-26 | $7700.00 | Window Closed / Lapsed |