US4358766A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Jamming signal reduction system
Assignee: Lockheed Martin Corp
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Filing: 1974-07-01
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Granted: 1982-11-09
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Expires: 1994-07-01
Abstract
Abstract Improved radar system performance in a jamming environment is achieved by making a complete frequency analysis of the jamming power entering the radar receiver during each range sweep (once per transmitted pulse) and then setting the frequency of the next transmitted pulse to the value which corresponds to the minimum jamming power measured.
Inventors
- 👤 Martin E. Mehron
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:17
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/36
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
88 words
In a frequency agile radar, apparatus for transmitting a frequency which corresponds to a low jamming frequency, comprising: means for sampling a portion of the input to the radar during the dead time of the radar receiver; means for measuring said sampled portion of the input to determine the frequency of the minimum received total jamming power; and means for controlling the frequency of the signal to be transmitted by the radar on the next pulse to correspond to the frequency of the minimum received total jamming power.
Claim 2
Dependent Claim
88 words
In a frequency agile radar, apparatus for transmitting a frequency which corresponds to a low jamming frequency, comprising: means for sampling a portion of the input to the radar during the dead time of the radar receiver; means for measuring said sampled portion of the input to determine the frequency of the minimum received total jamming power; and means for controlling the frequency of the signal to be transmitted by the radar on the next pulse to correspond to the frequency of the minimum received total jamming power.
Claim 3
Dependent Claim
44 words
Apparatus as defined in claim 1, wherein said measuring means includes: means for measuring the power level versus frequency of the sampled input; and means for analyzing the measured power level versus frequency to determine the frequency of the minimum received total jamming power.
Claim 4
Dependent Claim
56 words
Apparatus as defined in claim 2, wherein said means for measuring the power level versus frequency of the sampled input includes: means for generating a swept frequency; means for mixing the output of said swept frequency generating means with the sampled input to generate an IF signal; and an AM detector coupled to said mixing means.
Claim 5
Dependent Claim
19 words
Apparatus as defined in claim 3, further including an I.F. amplifier coupling said mixing means and said AM detector.
Claim 6
Dependent Claim
66 words
Apparatus as defined in claim 2 wherein said analyzing means includes: a peak detector coupled to said power level versus frequency measuring means for storing the lowest value of power of the sampled input; and a sample and hold circuit coupled to said peak detector for enabling thereof for storing a voltage corresponding to the frequency of the lowest value of power of the sampled input.
Claim 7
Dependent Claim
25 words
Apparatus as defined in claim 5, further including means for applying the stored voltage in said sample and hold circuit to said frequency controlling means.
Claim 8
Dependent Claim
35 words
Apparatus as defined in claim 4, wherein said means for generating a swept frequency includes; means for generating a voltage ramp; and a voltage controlled oscillator coupled to said means for generating a voltage ramp.
Claim 9
Dependent Claim
66 words
Apparatus as defined in claim 7, wherein said analyzing means includes: a peak detector coupled to said AM detector; and a sample and hold circuit enabled by said peak detector and having as an input thereto an output from said means for generating a ramp voltage whereby said sample and hold circuit stores a voltage proportional to the frequency at which jamming power is a minimum.
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) | 1985-11-08 | 1986-05-10 | 1986-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-11-08 | 1990-05-10 | 1990-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-11-08 | 1994-05-10 | 1994-11-09 | $7700.00 | Window Closed / Lapsed |