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US4398199A Expired / Lapsed US ⏱️ 0.0 years remaining

Circularly polarized microstrip line antenna

Assignee: KEC Electronic Industry Development Center
•
Filing: 1981-03-05
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Granted: 1983-08-09
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Expires: 2001-03-05
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Abstract

Abstract A circularly polarized microstrip line antenna for receiving or transmitting a signal of a particular wavelength includes a dielectric substrate having a ground plate provided on one surface thereof and having a microstrip line formed on another surface thereof. The microstrip line has an omega shaped fundamental portion composed of a loop portion and a pair of straight portions. The loop portion is one of either a regular polygon or a continuous closed curve having a length equal to the particular wavelength. The loop portion is symmetric about an axis which is on one of the surfaces of the substrate and is at right angles to the straight portions of the microstrip line.

Inventors

  • 👤 Toshio Makimoto
  • 👤 Sadahiko Nishimura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 21:57
CPC Classifications
H; H01; H01Q; H01Q21/00; H01Q21/24; H01Q11/00; H01Q11/02; H01Q13/00; H01Q13/20; H01Q13/206; H01Q21/06; H01Q21/061; H01Q21/065; H01Q21/068

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 188 words
A circularly polarized microstrip line antenna for receiving or transmitting a signal of a particular wavelength comprising: a dielectric substrate having a ground plate provided on one surface thereof and having a microstrip line formed on another surface thereof; wherein said microstrip line has an omega shaped fundamental portion composed of a loop portion and a pair of straight portions; and wherein said loop portion is a regular polygon having a length λg equal to said particular wavelength; and wherein said loop portion is symmetrical about an axis which is on one of said surfaces of said substrate and is at right angles to said straight portions of said microstrip line; and wherein an angle α is defined by one of said pair of straight portions and a side of the polygon connected to said straight portion, said angle α being obtained by the equation: ##EQU5## where θ m is the direction of a main beam of said antenna and η is an effective wavelength reduction rate thereof; and wherein a total length of said pair of straight portions d is obtained by the equation: d=λg/(1-η cos θ.sub.m).
Claim 2
Dependent Claim 188 words
A circularly polarized microstrip line antenna for receiving or transmitting a signal of a particular wavelength comprising: a dielectric substrate having a ground plate provided on one surface thereof and having a microstrip line formed on another surface thereof; wherein said microstrip line has an omega shaped fundamental portion composed of a loop portion and a pair of straight portions; and wherein said loop portion is a regular polygon having a length λg equal to said particular wavelength; and wherein said loop portion is symmetrical about an axis which is on one of said surfaces of said substrate and is at right angles to said straight portions of said microstrip line; and wherein an angle α is defined by one of said pair of straight portions and a side of the polygon connected to said straight portion, said angle α being obtained by the equation: ##EQU5## where θ m is the direction of a main beam of said antenna and η is an effective wavelength reduction rate thereof; and wherein a total length of said pair of straight portions d is obtained by the equation: d=λg/(1-η cos θ.sub.m).
Claim 3
Dependent Claim 17 words
A circularly polarized microstrip line antenna according to claim 1, wherein said loop portion is a square.
Claim 4
Dependent Claim 17 words
A circularly polarized microstrip line antenna according to claim 1, wherein said loop portion is a hexagon.

References Cited (Backward Citations)

US4160976A Cited
US4335385A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-08-08 1987-02-07 1987-08-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-08-08 1991-02-07 1991-08-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-08-08 1995-02-07 1995-08-09 $7700.00 Window Closed / Lapsed

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