Patent US4225866A successfully refreshed from Google Patents.
US4225866A
Expired / Lapsed
US
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Automatic failure-resistant radar transmitter
Assignee: ITT Inc
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Filing: 1978-10-27
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Granted: 1980-09-30
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Expires: 1998-10-27
Abstract
Abstract Apparatus is shown for controlling pulse width in pulsed, step-wise frequency modulated transmitters employing relatively long pulse widths and receiving pulse compression. Also disclosed is a pulsed pseudo-random coded radar system having fixed code word duration. Individual solid-state, RF power amplifier modules are paralleled, all spares included, and the full parallel group is operated at a power level such that individual units operate substantially below maximum power rating. RF solid-state device life is thereby increased. Failures of individual solid-state modules are recognized by a power monitor which operates to lengthen the pulse width in the FM staircase embodiment and to increase power supply input and, therefore, peak pulse power in the pseudo-random coded embodiment, thereby restoring average nominal transmitter power, notwithstanding one or more failed solid-state RF amplifiers.
Inventors
- 👤 Arnold M. Levine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:35
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/28; G01S7/282
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
171 words
A failure resistant pulsed radar system transmitter of the FM chirp type comprising: first means having a radio frequency input and radio frequency power output and N substantially identical solid-state radio frequency amplifier units operating in parallel electrically and each contributing 1/N of the predetermined level of the total output power of said transmitter, said units each operating at a power level below its maximum rating; second means comprising apparatus for providing successive pulses of radio frequency energy for driving said first means, said second means varying the transmitted frequency throughout each of said successive pulses; third means responsive to said first means power output for developing a control signal as a function of said total output power, and for applying said control signal in a manner to maintain said total output power substantially at said predetermined level by modifying the duration of each of said successive pulses; and fourth means within said first means for substantially isolating failed ones of said modules for limiting interaction with the remaining operative modules.
Claim 2
Dependent Claim
171 words
A failure resistant pulsed radar system transmitter of the FM chirp type comprising: first means having a radio frequency input and radio frequency power output and N substantially identical solid-state radio frequency amplifier units operating in parallel electrically and each contributing 1/N of the predetermined level of the total output power of said transmitter, said units each operating at a power level below its maximum rating; second means comprising apparatus for providing successive pulses of radio frequency energy for driving said first means, said second means varying the transmitted frequency throughout each of said successive pulses; third means responsive to said first means power output for developing a control signal as a function of said total output power, and for applying said control signal in a manner to maintain said total output power substantially at said predetermined level by modifying the duration of each of said successive pulses; and fourth means within said first means for substantially isolating failed ones of said modules for limiting interaction with the remaining operative modules.
Claim 3
Dependent Claim
33 words
Apparatus according to claim 1 in which said means for varying the transmitted frequency within each of said pulses includes means for effecting said frequency variation in discrete steps approximating a linear variation.
Claim 4
Dependent Claim
55 words
Apparatus according to claim 2 in which said third means comprises circuits for monitoring said power output to develop an analog thereof and for developing said control signal by comparison of said analog to a reference, said control signal being applied to determine the duration of said transmitted pulses in integral numbers of said steps.
Claim 5
Dependent Claim
49 words
Apparatus according to claim 1 which a temperature transducer in included for sensing the operating temperature of said solid-state units to develop and apply a temperature derived signal to said third means to limit the duration of said transmitted pulses and therefore the power dissipation of said solid-state units.
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) | 1983-09-30 | 1984-03-31 | 1984-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-30 | 1988-03-31 | 1988-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-30 | 1992-03-31 | 1992-09-30 | $7700.00 | Window Closed / Lapsed |