US3893117A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Marine radar transmission and reception system
Assignee: Tokyo Keiki Inc
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Filing: 1973-05-08
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Granted: 1975-07-01
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Expires: 1993-05-08
Abstract
Abstract A marine radar transmission and reception system in which first and second transmission pulse radar waves are emitted as first and second pulse radar waves from first and second radar antennae or a common radar antenna; reflected waves of the first and second emitted pulse radar waves are received as first and second received pulse radar waves by the first and second radar antennae or the common radar antenna; the modes of the first and second transmission pulse radar waves are selected in cooperation with those of the first and second radar antennae or that of the common radar antenna so that the first and second received pulse radar waves may be received by the first and second radar antennae or the common radar antenna independently of each other; a quotient or difference output corresponding to the quotient or difference of the first and second received pulse radar waves or the first and second received outputs based thereon is obtained; and sea clutter eliminated received pulse radar waves or outputs based thereon that signal components of the period-in which the quotient or difference output exceeds one predetermined threshold value or lies between two threshold values-are eliminated or suppressed, are obtained.
Inventors
- 👤 Tomiji Nirasawa
- 👤 Hiroshi Ota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:06
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/28; G01S7/285; G01S7/292; G01S7/2921; G01S13/00; G01S13/02; G01S13/06; G01S13/08; G01S13/10; G01S13/106; G01S7/024; G01S7/025
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
216 words
A marine radar transmission and reception system comprising: a. means for sequentially generating first and second transmission pulse radar waves of first and second pulse widths, respectively; b. an antenna for sequentially emitting the first and second transmission pulse radar waves in the same direction as first and second emitted pulse radar waves respectively and sequentially receiving first and second reflected pulse radar waves of the first and second emitted pulse radar waves; c. a receiving circuit supplied with the output of the antenna; d. means for producing first and second received pulse waves corresponding to the first and second reflected pulse radar waves from the output of the receiving circuit, respectively; e. a gate circuit for gating the output of the receiving circuit or either one of the first and second received pulse waves; and f. control means having a quotient circuit for producing the quotient output of the first and second received pulse waves, a setting circuit for deriving a predetermined threshold value output and a detector for detecting whether or not the quotient is in excess of the threshold value output; g. in which the gate circuit is controlled with the output of the detector of the control means, whereby sea clutter eliminated received pulse radar waves are obtained from the gate circuit.
Claim 2
Dependent Claim
216 words
A marine radar transmission and reception system comprising: a. means for sequentially generating first and second transmission pulse radar waves of first and second pulse widths, respectively; b. an antenna for sequentially emitting the first and second transmission pulse radar waves in the same direction as first and second emitted pulse radar waves respectively and sequentially receiving first and second reflected pulse radar waves of the first and second emitted pulse radar waves; c. a receiving circuit supplied with the output of the antenna; d. means for producing first and second received pulse waves corresponding to the first and second reflected pulse radar waves from the output of the receiving circuit, respectively; e. a gate circuit for gating the output of the receiving circuit or either one of the first and second received pulse waves; and f. control means having a quotient circuit for producing the quotient output of the first and second received pulse waves, a setting circuit for deriving a predetermined threshold value output and a detector for detecting whether or not the quotient is in excess of the threshold value output; g. in which the gate circuit is controlled with the output of the detector of the control means, whereby sea clutter eliminated received pulse radar waves are obtained from the gate circuit.
Claim 3
Dependent Claim
214 words
A marine radar transmission and reception system comprising: a. means for generating transmission pulse radar waves; b. first and second antennae for sequentially emitting the transmission pulse radar waves in the same direction as first and second emitted pulse radar waves of first and second beam widths respectively and sequentially receiving first and second reflected pulse radar waves of the first and second emitted pulse radar waves respectively; c. a receiving circuit supplied with the outputs of the first and second antennae; d. means for producing first and second received pulse waves corresponding to the first and second reflected pulse radar waves from the output of the receiving circuit, respectively; e. a gate circuit for gating the output of the receiving circuit or either one of the first and second received pulse waves; and f. control means having a quotient circuit for producing the quotient output of the first and second received pulse waves, a setting circuit for deriving a predetermined threshold value output and a detector for detecting whether or not the quotient is in excess of the threshold value output; g. in which the gate circuit is controlled with the output of the detector of the control means, whereby sea clutter eliminated received pulse radar waves are obtained from the gate circuit.
Claim 4
Dependent Claim
214 words
A marine radar transmission and reception system comprising: a. means for generating transmission pulse radar waves; b. first and second antennae for sequentially emitting the transmission pulse radar waves in the same direction as first and second emitted pulse radar waves of first and second beam widths respectively and sequentially receiving first and second reflected pulse radar waves of the first and second emitted pulse radar waves respectively; c. a receiving circuit supplied with the outputs of the first and second antennae; d. means for producing first and second received pulse waves corresponding to the first and second reflected pulse radar waves from the output of the receiving circuit, respectively; e. a gate circuit for gating the output of the receiving circuit or either one of the first and second received pulse waves; and f. control means having a quotient circuit for producing the quotient output of the first and second received pulse waves, a setting circuit for deriving a predetermined threshold value output and a detector for detecting whether or not the quotient is in excess of the threshold value output; g. in which the gate circuit is controlled with the output of the detector of the control means, whereby sea clutter eliminated received pulse radar waves are obtained from the gate circuit.
Claim 5
Dependent Claim
236 words
A marine radar transmission and reception system comprising: a. means for sequentially generating first and second transmission pulse radar waves of first and second pulse widths, respectively; b. an antenna for sequentially emitting the first and second transmission pulse radar waves in the same direction as first and second emitted pulse radar waves respectively and sequentially receiving first and second reflected pulse radar waves of the first and second emitted pulse radar waves; c. a receiving circuit supplied with the output of the antenna; d. means for producing first and second received pulse waves corresponding to the first and second reflected pulse radar waves from the output of the receiving circuit, respectively; e. a parallel circuit of first and second gate circuits gating the output of the receiving circuit or either one of the first and second received pulse waves; and f. control means having a quotient circuit for producing the quotient of the first and second received pulse waves, first and second setting circuits for deriving first and second predetermined threshold value outputs respectively, and first and second detectors for detecting whether or not the quotient is in excess of the first and second threshold value outputs respectively; g. in which the first and second gate circuits are controlled with outputs of the first and second detectors of the control means, respectively, whereby sea clutter eliminated received pulse waves are obtained from the parallel circuit.
Claim 6
Dependent Claim
236 words
A marine radar transmission and reception system comprising: a. means for sequentially generating first and second transmission pulse radar waves of first and second pulse widths, respectively; b. an antenna for sequentially emitting the first and second transmission pulse radar waves in the same direction as first and second emitted pulse radar waves respectively and sequentially receiving first and second reflected pulse radar waves of the first and second emitted pulse radar waves; c. a receiving circuit supplied with the output of the antenna; d. means for producing first and second received pulse waves corresponding to the first and second reflected pulse radar waves from the output of the receiving circuit, respectively; e. a parallel circuit of first and second gate circuits gating the output of the receiving circuit or either one of the first and second received pulse waves; and f. control means having a quotient circuit for producing the quotient of the first and second received pulse waves, first and second setting circuits for deriving first and second predetermined threshold value outputs respectively, and first and second detectors for detecting whether or not the quotient is in excess of the first and second threshold value outputs respectively; g. in which the first and second gate circuits are controlled with outputs of the first and second detectors of the control means, respectively, whereby sea clutter eliminated received pulse waves are obtained from the parallel circuit.
Claim 7
Dependent Claim
233 words
A marine radar transmission and reception system comprising: a. means for generating transmission pulse radar waves; b. first and second antennae for sequentially emitting the transmission pulse radar waves in tHe same direction as first and second emitted pulse radar waves of first and second beam widths respectively and sequentially receiving first and second reflected pulse radar waves of the first and second emitted pulse radar waves respectively; c. a receiving circuit supplied with the outputs of the first and second antennae; d. means for producing first and second received pulse corresponding to the first and second reflected pulse radar waves from the output of the receiving circuit, respectively; e. a parallel circuit of first and second gate circuits gating the output of the receiving circuit or either one of the first and second received pulse waves; and f. control means having a quotient circuit for producing the quotient of the first and second received pulse waves, first and second setting circuits for deriving first and second predetermined threshold value outputs respectively, and first and second detectors for detecting whether or not the quotient is in excess of the first and second threshold value outputs respectively; g. in which the first and second gate circuits are controlled with outputs of the first and second detectors of the control means, respectively, whereby sea clutter eliminated received pulse waves are obtained from the parallel circuit.
Claim 8
Dependent Claim
233 words
A marine radar transmission and reception system comprising: a. means for generating transmission pulse radar waves; b. first and second antennae for sequentially emitting the transmission pulse radar waves in tHe same direction as first and second emitted pulse radar waves of first and second beam widths respectively and sequentially receiving first and second reflected pulse radar waves of the first and second emitted pulse radar waves respectively; c. a receiving circuit supplied with the outputs of the first and second antennae; d. means for producing first and second received pulse corresponding to the first and second reflected pulse radar waves from the output of the receiving circuit, respectively; e. a parallel circuit of first and second gate circuits gating the output of the receiving circuit or either one of the first and second received pulse waves; and f. control means having a quotient circuit for producing the quotient of the first and second received pulse waves, first and second setting circuits for deriving first and second predetermined threshold value outputs respectively, and first and second detectors for detecting whether or not the quotient is in excess of the first and second threshold value outputs respectively; g. in which the first and second gate circuits are controlled with outputs of the first and second detectors of the control means, respectively, whereby sea clutter eliminated received pulse waves are obtained from the parallel circuit.
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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) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |