US4990927A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microstrip antenna
Assignee: Aisin Corp
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Filing: 1989-03-27
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Granted: 1991-02-05
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Expires: 2009-03-27
Abstract
Abstract A microstrip antenna has a rectangularly-shaped radiation conductive plate attached to one side of a dielectric plate, with a grounding conductive plate being attached to the other side of the dielectric plate. Rectangular line loads extend from adjacent sides of the radiation conductive plate. With such a configuration, the antenna retains all of the advantages of a microstrip antenna, including light weight, compactness, ease of manufacture, and a low profile, while enabling operation at multiple frequencies (four, on one embodiment), or polarization at multiple frequencies (two, in another embodiment).
Inventors
- 👤 Kiyokazu Ieda
- 👤 Yuichi Murakami
- 👤 Takashi Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:48
CPC Classifications
H; H01; H01Q; H01Q9/00; H01Q9/04; H01Q9/0407; H01Q5/00; H01Q5/30; H01Q5/307; H01Q5/342; H01Q5/357; H01Q5/364
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
144 words
A microstrip antenna comprising: a dielectric plate member having two major surfaces and a thickness which is small compared to a wavelength of electromagnetic radiation, a rectangular radiation conductive plate member connected along one major surface of said dielectric plate member, a grounding conductive plate member connected along the other major surface of said dielectric plate member, an electric power supply point connected to the rectangular radiation conductive plate member through the dielectric plate member, and said rectangular radiation conductive plate member including first and second portions defined as line loads respectively extending from the middle of each of two adjacent sides of said rectangular radiation conductive plate member and in the same plane as said rectangular radiation conductive plate member, said first and second portions being sized so as to be resonant, and such that said microstrip antenna resonates at four different frequencies.
Claim 2
Dependent Claim
144 words
A microstrip antenna comprising: a dielectric plate member having two major surfaces and a thickness which is small compared to a wavelength of electromagnetic radiation, a rectangular radiation conductive plate member connected along one major surface of said dielectric plate member, a grounding conductive plate member connected along the other major surface of said dielectric plate member, an electric power supply point connected to the rectangular radiation conductive plate member through the dielectric plate member, and said rectangular radiation conductive plate member including first and second portions defined as line loads respectively extending from the middle of each of two adjacent sides of said rectangular radiation conductive plate member and in the same plane as said rectangular radiation conductive plate member, said first and second portions being sized so as to be resonant, and such that said microstrip antenna resonates at four different frequencies.
Claim 3
Dependent Claim
40 words
A microstrip antenna as recited in claim 1, wherein said first and second portions each comprise a rectangular conductive plate member which is symmetrical with respect to a center line of one side of said rectangular radiation conductive plate member.
Claim 4
Dependent Claim
159 words
A microstrip antenna comprising: a dielectric plate member having two major surfaces and a thickness which is small compared to a wavelength of electromagnetic radiation, a rectangular radiation conductive plate member connected along one major surface of said dielectric plate member, a grounding conductive plate member connected along the other major surface of said dielectric plate member, a single electric power supply point connected to the rectangular radiation conductive member through the dielectric plate member, and said rectangular radiation conductive plate member including first and second portions defined as line loads respectively extending from the middle of each of two adjacent sides of said rectangular radiation conductive plate member, and in the same plane as said rectangular radiation conductive plate member, said first and second portions further being sized so as to be resonant so as to produce a 90 degree phase difference in input admittance in a parallel exciting mode which is parallel to the two adjacent sides.
Claim 5
Dependent Claim
159 words
A microstrip antenna comprising: a dielectric plate member having two major surfaces and a thickness which is small compared to a wavelength of electromagnetic radiation, a rectangular radiation conductive plate member connected along one major surface of said dielectric plate member, a grounding conductive plate member connected along the other major surface of said dielectric plate member, a single electric power supply point connected to the rectangular radiation conductive member through the dielectric plate member, and said rectangular radiation conductive plate member including first and second portions defined as line loads respectively extending from the middle of each of two adjacent sides of said rectangular radiation conductive plate member, and in the same plane as said rectangular radiation conductive plate member, said first and second portions further being sized so as to be resonant so as to produce a 90 degree phase difference in input admittance in a parallel exciting mode which is parallel to the two adjacent sides.
Claim 6
Dependent Claim
40 words
A microstrip antenna as recited in claim 3, wherein said first and second portions each comprise a rectangular conductive plate member which is symmetrical with respect to the center line of one side of said rectangular radiation conductive plate member.
Claim 7
Dependent Claim
31 words
A microstrip antenna as recited in claim 3, wherein said first and second portions are configured such that said microstrip antenna performs said frequency polarization at at least two different frequencies.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-02-04 | 1994-08-06 | 1995-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-04 | 1998-08-06 | 1999-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-04 | 2002-08-06 | 2003-02-05 | $7700.00 | Window Closed / Lapsed |