US4475107A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circularly polarized microstrip line antenna
Assignee: KEC Electronic Industry Development Center
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Filing: 1981-12-07
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Granted: 1984-10-02
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Expires: 2001-12-07
Abstract
Abstract A circularly polarized microstrip line antenna has a dielectric substrate having a ground plate formed on one surface thereof and at least a pair of stripline conductors on the other surface. Each stripline conductor consists of a plurality of crank type fundamental elements, each element consists of a pair of straight portions each having a length a, and U-shaped portion consisting of a pair of arm pieces, each having a length b, and a single base piece having a length c. The lengths a, b and c are chosen to satisfy the following equations: 0<b≦1/2λg where λg is a guide wavelength, 2a={(-n-m∓T)λg-b}/(1-η cos θm) where m and n are integers, T=1/π Tan.sup.-1 {sin θm/(1-η cos θm)} η=λg/λ.sub.0 where θm is an angle of main beam direction, η is the effective wavelength reduction rate and, λ 0 is free space wavelength and: C=}(m±T)λg-b}/(1-η cos θm) optimally, b=3/8λg.
Inventors
- 👤 Toshio Makimoto
- 👤 Sadahiko Nishimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:58
CPC Classifications
H; H01; H01Q; H01Q21/00; H01Q21/24; H01Q11/00; H01Q11/02; H01Q13/00; H01Q13/20; H01Q13/206; H01Q21/06; H01Q21/061; H01Q21/068
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
188 words
A circularly polarized microstrip line antenna wherein there are provided a dielectric substrate having a ground plate formed on one surface thereof and at least one pair of stripline conductors which are bent periodically on the other surface and which are supplied with a travelling-wave, wherein each stripline conductor consists of a plurality of crank type fundamental elements, each element consists of a pair of straight portions each having a length a, and U-shaped portion consisting of a pair of arm pieces each having a length b, and a single base piece having a length c, the straight portions of each stripline conductor are aligned in an imaginary straight line, the elements are aligned so that the U-shaped portions are in a same orientation, these lengths a, b and c are chosen to satisfy the following equations: b=(3λ.sub.g /8) where λg is a guide wavelength, 2a=[(-n-m∓T)λg-b]/(1-η cos θm) where m and n are integers, T=1/π Tan.sup.-1 [sin θm/(1-η cos θm)] η=λg/λ.sub.0 where θm is an angle of main beam direction, η is an effective wavelength reduction rate, and λ 0 is free space wavelength, and C=[(m±T)λg-b]/(1-η cos θm)
Claim 2
Dependent Claim
188 words
A circularly polarized microstrip line antenna wherein there are provided a dielectric substrate having a ground plate formed on one surface thereof and at least one pair of stripline conductors which are bent periodically on the other surface and which are supplied with a travelling-wave, wherein each stripline conductor consists of a plurality of crank type fundamental elements, each element consists of a pair of straight portions each having a length a, and U-shaped portion consisting of a pair of arm pieces each having a length b, and a single base piece having a length c, the straight portions of each stripline conductor are aligned in an imaginary straight line, the elements are aligned so that the U-shaped portions are in a same orientation, these lengths a, b and c are chosen to satisfy the following equations: b=(3λ.sub.g /8) where λg is a guide wavelength, 2a=[(-n-m∓T)λg-b]/(1-η cos θm) where m and n are integers, T=1/π Tan.sup.-1 [sin θm/(1-η cos θm)] η=λg/λ.sub.0 where θm is an angle of main beam direction, η is an effective wavelength reduction rate, and λ 0 is free space wavelength, and C=[(m±T)λg-b]/(1-η cos θm)
Claim 3
Dependent Claim
68 words
The circularly polarized microstrip line antenna as claimed in claim 1, wherein said at least one pair of stripline conductors are parallel to each other in a plane, the U-shaped portions of the stripline conductors are aligned in parallel to the U-shaped portions of the other stripline conductors and the position of the U-shaped portions deviates from the positions of the U-shaped portions of the other stripline conductor.
Claim 4
Dependent Claim
34 words
The circularly polarized microstrip line antenna as claimed in claim 1, wherein a plurality of sets of pairs of stripline conductors are provided, each pair being parallel to every other pair in a plane.
Claim 5
Dependent Claim
46 words
The circularly polarized microstrip line antenna as claimed in claim 1, wherein said at least one pair of stripline conductors are arranged side by side in a point symmetrical relationship, with the feed point being set as an approximate center for feeding from the central portion.
Claim 6
Dependent Claim
56 words
The circularly polarized microstrip line antenna as claimed in claim 1, wherein a plurality of sets of pairs of stripline conductors are provided in a regular arrangement so that said stripline conductors are arranged in a plurality of rows and in a parallel relationship, with the feed point being set at one end of the substrate.
Claim 7
Dependent Claim
41 words
The circularly polarized microstrip line antenna as claimed in claim 5, wherein a plurality of sets of stripline conductors are provided in a plane so as to form a multiple-array configuration with the feed point being set at central position thereof.
References Cited (Backward Citations)
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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) | 1987-10-02 | 1988-04-02 | 1988-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-02 | 1992-04-02 | 1992-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-02 | 1996-04-02 | 1996-10-02 | $7700.00 | Window Closed / Lapsed |