Patent US3845481A successfully refreshed from Google Patents.
US3845481A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Target controlled agc for scan radar normalization
Assignee: RTX Corp
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Filing: 1973-04-26
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Granted: 1974-10-29
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Expires: 1993-04-26
Abstract
Abstract In a track-while-scan radar which pinpoints a target location by comparing target return voltage summations in the early half of a range gate (E) with those in the late half of the range gate (L), and with the target return voltage summations in the port half of a multi-pulse azimuth gate (P) with those in the starboard half of the azimuth gate (S) normalization of target return signal strength is eliminated by using an automatic gain control (AGC) level which is chosen as the lowest value of the early, late, port and starboard target return voltage summations, thereby using only the least, track-gated portion of the target return signal within the target window in one scan to establish the level of all of the track-gated target returns (E, L, P, S) for a succeeding scan.
Inventors
- 👤 P Danzer
- 👤 M Greenspan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:36
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/66; G01S13/72
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
98 words
In a scanning pulse radar system having processing means providing tracking gates for automatic cursor tracking of designated targets in response to video levels of target return signals falling in said tracking gates, the improvement comprising: means for selecting in each scan of the radar system the lowest video level from among the video levels respectively corresponding to each of the tracking gates; and means responsive to said last named means for controlling the gain of the receiver of said radar system in a succeeding scan in response to the lowest video level selected during a preceding scan.
Claim 2
Dependent Claim
98 words
In a scanning pulse radar system having processing means providing tracking gates for automatic cursor tracking of designated targets in response to video levels of target return signals falling in said tracking gates, the improvement comprising: means for selecting in each scan of the radar system the lowest video level from among the video levels respectively corresponding to each of the tracking gates; and means responsive to said last named means for controlling the gain of the receiver of said radar system in a succeeding scan in response to the lowest video level selected during a preceding scan.
Claim 3
Dependent Claim
169 words
A tracking radar system comprising: means including a scanning antenna, a pulse transmitter, and a receiver having a controllable gain, for illuminating successive portions of a scanned area with a pulsed radar energy and receiving return signals reflected from targets located in said area and providing at the output of the receiver video signals representative of the target reflections; processing means including cursor means identifying a point within said area for providing tracking gates in range and azimuth centered about said point, said processing means adjusting the position of the point defined by said cursor means in response to video signal levels falling within said tracking gates; means responsive to the video signals falling within said tracking gates for selecting the lowest level video signal within said tracking gates during each scan; means for storing the lowest video signal selected in one scan; and AGC means responsive to the lowest video signal level stored in one scan for controlling the gain of said radar receiver during a succeeding scan.
Claim 4
Dependent Claim
169 words
A tracking radar system comprising: means including a scanning antenna, a pulse transmitter, and a receiver having a controllable gain, for illuminating successive portions of a scanned area with a pulsed radar energy and receiving return signals reflected from targets located in said area and providing at the output of the receiver video signals representative of the target reflections; processing means including cursor means identifying a point within said area for providing tracking gates in range and azimuth centered about said point, said processing means adjusting the position of the point defined by said cursor means in response to video signal levels falling within said tracking gates; means responsive to the video signals falling within said tracking gates for selecting the lowest level video signal within said tracking gates during each scan; means for storing the lowest video signal selected in one scan; and AGC means responsive to the lowest video signal level stored in one scan for controlling the gain of said radar receiver during a succeeding scan.
Claim 5
Dependent Claim
47 words
A tracking radar system according to claim 2 wherein said AGC means comprises means responsive to the tracking gates for controlling the gain of the receiver in response to the lowest video level stored during a preceding scan only during the time coextensive with the tracking gates.
Claim 6
Dependent Claim
35 words
A tracking radar system according to claim 3 wherein said AGC means further comprises means for controlling the gain of said radar receiver to have predetermined gain during time periods exclusive of said tracking gates.
Claim 7
Dependent Claim
59 words
A tracking radar system according to claim 2 wherein said selecting means comprises a plurality of comparison circuits responsive to the video levels within the respective tracking gates for generating related signals indicative of the lowest of said video levels; and means responsive to said related signals for providing the lowest of said video levels to said storage means.
Claim 8
Dependent Claim
66 words
The tracking radar according to claim 2 wherein said storage means comprises a pair of storage devices in series with each other, one actuated at the end of one scan to store the lowest video level selected during said one scan, the second of said storage devices receiving the video level stored in the first of said storage devices at the start of A succeeding scan.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-28 | 1978-04-29 | 1978-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-28 | 1982-04-29 | 1982-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-28 | 1986-04-29 | 1986-10-29 | $7700.00 | Window Closed / Lapsed |