US5202651A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Band-stop filter circuit suitably made into monolithic microwave integrated circuits
Assignee: Sharp Corp
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Filing: 1991-12-24
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Granted: 1993-04-13
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Expires: 2011-12-24
Abstract
Abstract An image band-stop filter circuit includes a transmission line formed on a substrate of GaAs and a T circuit connected in parallel to the transmission line and having a high pass filter characteristic. The T circuit includes series-connected first and second capacitances connected in parallel to the transmission line and a stub having one end connected to a node between the first and second capacitances and the other end short-circuited. The stub has a line length which becomes inductive in an image signal band to be removed. As a result, the lengths of the transmission line and the stub can be reduced to enable the band-stop filter circuit to be made into a MMIC with ease while achieving an excellent signal transmission characteristic.
Inventors
- 👤 Toshihiko Yoshimasu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:19
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/01; H03H7/0123; H03H7/17; H03H7/1708
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
91 words
A band-stop filter circuit comprising: input and output terminals, a transmission line connecting said input and output terminals, and a T circuit connected in parallel to said transmission line, said T circuit including: series-connected first and second capacitance means connected in parallel to said transmission line, and a stub having one end connected to a node between said first and second capacitance means and the other end short-circuited, said stub having a line length which becomes inductive in an undesired signal band so as to filter out said undesired signal band.
Claim 2
Dependent Claim
91 words
A band-stop filter circuit comprising: input and output terminals, a transmission line connecting said input and output terminals, and a T circuit connected in parallel to said transmission line, said T circuit including: series-connected first and second capacitance means connected in parallel to said transmission line, and a stub having one end connected to a node between said first and second capacitance means and the other end short-circuited, said stub having a line length which becomes inductive in an undesired signal band so as to filter out said undesired signal band.
Claim 3
Dependent Claim
22 words
The band-stop filter circuit according to claim 1, wherein said transmission line and said stub have characteristic impedances equal to each other.
Claim 4
Dependent Claim
23 words
The band-stop filter circuit according to claim 1, wherein the characteristic impedance of said stub is larger than that of said transmission line.
Claim 5
Dependent Claim
25 words
The band-stop filter circuit according to claim 1, wherein said transmission line and said T circuit are formed on a semiconductor substrate of GaAs material.
Claim 6
Dependent Claim
25 words
The band-stop filter circuit according to claim 1, wherein said transmission line and said T circuit are formed on a semiconductor substrate of InP material.
Claim 7
Dependent Claim
22 words
The band-stop filter circuit according to claim 1, wherein said transmission line and said T circuit are formed on a dielectric substrate.
Claim 8
Dependent Claim
22 words
The band-stop filter circuit according to claim 1, wherein said first and second capacitance means have capacitance values equal to each other.
Claim 9
Dependent Claim
125 words
A band-stop filter circuit comprising: input and output terminals, a first transmission line connecting said input and output terminals, and a T circuit connected in parallel to said first transmission line, said T circuit comprising; series-connected first and second capacitance means connected in parallel to said first transmission line, a second transmission line-connected in series between said input terminal and said first capacitance means, a third transmission line connected in series between said output terminal and said second capacitance means, and a stub having one end connected to a node between said first and second capacitance means and the other end short-circuited, said stub having a line length which becomes inductive in an undesired signal band so as to filter out said undesired signal band.
Claim 10
Dependent Claim
125 words
A band-stop filter circuit comprising: input and output terminals, a first transmission line connecting said input and output terminals, and a T circuit connected in parallel to said first transmission line, said T circuit comprising; series-connected first and second capacitance means connected in parallel to said first transmission line, a second transmission line-connected in series between said input terminal and said first capacitance means, a third transmission line connected in series between said output terminal and said second capacitance means, and a stub having one end connected to a node between said first and second capacitance means and the other end short-circuited, said stub having a line length which becomes inductive in an undesired signal band so as to filter out said undesired signal band.
Claim 11
Dependent Claim
29 words
The band-stop filter circuit according to claim 8, wherein the characteristic impedance of said stub is larger than the characteristic impedances of said first, second and third transmission lines.
Claim 12
Dependent Claim
25 words
The band-stop filter circuit according to claim 8, wherein said transmission line and said T circuit are formed on a semiconductor substrate of GaAs material.
Claim 13
Dependent Claim
25 words
The band-stop filter circuit according to claim 8, wherein said transmission line and said T circuit are formed on a semiconductor substrate of InP material.
Claim 14
Dependent Claim
22 words
The band-stop filter circuit according to claim 8, wherein said transmission line and said T circuit are formed on a dielectric substrate.
Claim 15
Dependent Claim
22 words
The band-stop filter circuit according to claim 8, wherein said first and second capacitance means have capacitance values equal to each other.
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) | 1996-04-12 | 1996-10-12 | 1997-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-04-12 | 2000-10-12 | 2001-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-04-12 | 2004-10-12 | 2005-04-13 | $7700.00 | Window Closed / Lapsed |