Patent US4379996A successfully refreshed from Google Patents.
US4379996A
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Enhancement of class C operation of bipolar junction transistor
Assignee: Boeing North American Inc
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Filing: 1981-02-13
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Granted: 1983-04-12
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Expires: 2001-02-13
Abstract
Abstract Pulsed RF operation of a class C biased BJT is enhanced using a three element system to control the BJT emitter current. The three element system includes a transformer having a secondary connected in the emitter current path. Connected to the transformer primary are the other two elements, namely, an impedance and a pulse source. The three elements cooperate to cause the emitter current to substantially conform to a desired or predetermined pulse waveform.
Inventors
- 👤 Robert J. Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:00
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/20; H03F3/21; H03F3/189; H03F3/19
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
133 words
A circuit comprising a class C biased BJT which is for outputting RF bursts, and means for controlling the shape of the envelope of said RF burst, said shape controlling means comprising: first means comprising a transformer having a primary winding with M p turns and a secondary winding with M S turns where M p :M S >1, said secondary winding being connected in the BJT emitter current path, pulse source second means, connected to the primary winding, for providing pulses having predetermined parameters, impedance third means connected to the primary winding, said first, second, and third means cooperating to control the BJT emitter current and cause the BJT emitter current envelope to substantially conform to a predetermined function of time I e (t), where I e (t) is a pulse waveform.
Claim 2
Dependent Claim
133 words
A circuit comprising a class C biased BJT which is for outputting RF bursts, and means for controlling the shape of the envelope of said RF burst, said shape controlling means comprising: first means comprising a transformer having a primary winding with M p turns and a secondary winding with M S turns where M p :M S >1, said secondary winding being connected in the BJT emitter current path, pulse source second means, connected to the primary winding, for providing pulses having predetermined parameters, impedance third means connected to the primary winding, said first, second, and third means cooperating to control the BJT emitter current and cause the BJT emitter current envelope to substantially conform to a predetermined function of time I e (t), where I e (t) is a pulse waveform.
Claim 3
Dependent Claim
31 words
Apparatus as defined in claim 1 wherein the polarity of the second means pulses, and the phase of the secondary winding, are appropriate to aid, rather than oppose, emitter current flow.
Claim 4
Dependent Claim
16 words
Apparatus as defined in claim 2 wherein the second means pulses are substantially rectangular in shape.
Claim 5
Dependent Claim
16 words
Apparatus as defined in claim 3 wherein the impedance third means has substantially no reactance component.
Claim 6
Dependent Claim
25 words
Apparatus as defined in claims 1, 2, or 3 wherein the impedance third means has substantially no reactance component and has substantially no resistance component.
Claim 7
Dependent Claim
27 words
Apparatus as defined in claims 1, 2, 3, or 4 wherein said impedance third means includes a temperature variable resistance for reducing emitter current dependency on temperature.
Claim 8
Dependent Claim
27 words
Apparatus as defined in claims 1 or 2 wherein (i) said third means comprises a capacitor and (ii) said second means pulses are substantially rectangular in shape.
Claim 9
Dependent Claim
27 words
Apparatus as defined in claims 1 or 2 wherein (i) said third means comprises a capacitor and (ii) said second means pulses are substantially pseudo-Gaussian in shape.
Claim 10
Dependent Claim
21 words
Apparatus as defined in claim 1, 2, or 3 wherein the pulse waveform I e (t) is substantially rectangular in shape.
Claim 11
Dependent Claim
21 words
Apparatus as defined in claims 1, 2, or 3 wherein the pulse waveform I e (t) is substantially pseudo-Gaussian in shape.
Claim 12
Dependent Claim
102 words
Apparatus comprising: a class C biased BJT for outputting RF bursts, a transformer having (i) a primary winding with a first number of turns and (ii) a secondary winding with a second number of turns, said first number being greater than said second number, and said secondary winding being connected in the BJT emitter current path, means for providing pulses having predetermined parameters, and being connected to said primary winding for delivering pulses thereto, whereby, said pulses cause the BJT emitter current envelope to substantially conform to a predetermined function of time where said predetermined function of time is a pulse waveform.
Claim 13
Dependent Claim
102 words
Apparatus comprising: a class C biased BJT for outputting RF bursts, a transformer having (i) a primary winding with a first number of turns and (ii) a secondary winding with a second number of turns, said first number being greater than said second number, and said secondary winding being connected in the BJT emitter current path, means for providing pulses having predetermined parameters, and being connected to said primary winding for delivering pulses thereto, whereby, said pulses cause the BJT emitter current envelope to substantially conform to a predetermined function of time where said predetermined function of time is a pulse waveform.
Claim 14
Dependent Claim
24 words
Apparatus as defined in claim 11 wherein said pulse providing means includes a resistance means for having a predetermined effect on the pulse parameters.
Claim 15
Dependent Claim
22 words
Apparatus as defined in claim 12 wherein said resistance means includes a temperature variable resistance for reducing emitter current dependency on temperature.
Claim 16
Dependent Claim
24 words
Apparatus as defined in claim 11 wherein said pulse providing means includes a capacitance means for having a predetermined effect on said pulse parameters.
Claim 17
Dependent Claim
30 words
Apparatus as defined in claims 11, 12, 13, or 14 wherein the pulse providing means pulses have a shape which is a predetermined one of substantially rectangular or substantially pseudo-Gaussian.
References Cited (Backward Citations)
US4322689A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-04-11 | 1986-10-11 | 1987-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-11 | 1990-10-11 | 1991-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-11 | 1994-10-11 | 1995-04-12 | $7700.00 | Window Closed / Lapsed |