Leaky-wave antenna

• US 10,367,268 B2
• Filed: 02/19/2015
• Issued: 07/30/2019
• Est. Priority Date: 02/19/2015
• Status: Active Grant

• Current Assignee: Denki Kogyo Company Limited
• Original Assignee: Denki Kogyo Company Limited
• Inventors: Oshima, Ichiro, Seki, Takuya
• Primary Examiner(s): Tran, Hai V
• Application Number:
  US15/551,794
• Publication Number:
  US 20180040961A1
• Time in Patent Office: 1,622 Days
• Field of Search: 343777
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 13/20 Non-resonant leaky-waveguide or transmission-line antennas; Equivalent structures causing radiation along the transmission path of a guided wave
• CPC Class Codes: H01Q 15/0086 said selective devices having materials with a synthesized negative refractive index, e.g. metamaterials or left-handed materials
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 21/245 provided with means for varying the polarisation polarising devices H01Q15/24; tracking by comparing linear polarisation compounds G01S3/146; reducing depolarisation effects H04B7/00; polarisation diversity H04B7/10
• CPC Class Codes: H01Q 21/26 Turnstile or like antennas comprising arrangements of three or more elongated elements disposed radially and symmetrically in a horizontal plane about a common centre
• CPC Class Codes: H01Q 25/001 Crossed polarisation dual antennas orthomode horns H01Q13/0258; cross-polarised rear feeds H01Q19/136; orthomode transducers H01P1/161

Abstract

To provide a leaky-wave antenna that allows dual-polarization without limiting an emission range to either side. The antenna includes as an element unit (AE) a CRLH transmission line configured by multiply connecting CRLH unit cells (UC) in a periodic fashion between one ends and the other ends of two parallel lines (La, Lb). The respective unit cells (UC) have a left-handed series capacitor (C1, C2) on each of the two parallel lines (La, Lb) and have a left-handed parallel inductor (L1) between the two parallel lines (La, Lb). When power is fed between the two parallel lines (La, Lb), the two parallel lines (La, Lb) and the series capacitor (C1, C2) serve to emit a vertical polarization component, and the parallel inductor (L1) and a conductor between the two parallel lines (La, Lb) serve to emit a horizontal polarization component.

Claims

1. A leaky-wave antenna comprising as an element unit, a CRLH transmission line configured by multiply connecting CRLH unit cells in a periodic fashion between one ends and the opposite ends of two parallel lines,

wherein the unit cells each has a left-handed series capacitor on each of the two parallel lines and has a left-handed parallel inductor between the two parallel lines, and

when power is fed to the two parallel lines, the two parallel lines and the series capacitor serve to emit a vertical polarization component and also, the parallel inductor and a conductor between the two parallel lines serve to emit a horizontal polarization component.

2. The leaky-wave antenna according to claim 1, wherein the element unit is configured so that the vertical polarization component and the horizontal polarization component are emitted in equal amounts.

3. The leaky-wave antenna according to claim 1, wherein the element unit is configured to show a directivity, in a vertical plane, of an end-fire pattern.

4. A leaky-wave antenna comprising leaky-wave antennas according to claim 1 as first and second antennas, wherein the first and second antennas have element units that are combined orthogonal to each other with their longitudinal axial lines being aligned.

5. The leaky-wave antenna according to claim 4, wherein the element units of the first and second antennas are displaced from each other along the longitudinal axial line by half a length of the respective unit cells arrayed periodically.

6. The leaky-wave antenna according to claim 4, wherein the element units of the first and second antennas are configured so that their directivity in a vertical plane is of an end-fire pattern.

7. The leaky-wave antenna according to claim 4, further comprising a reflector for narrowing a beam width in a horizontal plane.

8. The leaky-wave antenna according to claim 4, wherein an interdigital capacitor or a parallel plate capacitor is used as the series capacitor.

9. The leaky-wave antenna according to claim 4, wherein a straight thin line or a meandering line is used as the parallel inductor.

10. The leaky-wave antenna according to claim 4, wherein a chipped element is used as the series capacitor and the parallel inductor.

11. The leaky-wave antenna according to claim 1, further comprising a reflector for narrowing a beam width in a horizontal plane.

12. The leaky-wave antenna according to claim 1, wherein an interdigital capacitor or a parallel plate capacitor is used as the series capacitor.

13. The leaky-wave antenna according to claim 1, wherein a straight thin line or a meandering line is used as the parallel inductor.

14. The leaky-wave antenna according to claim 1, wherein a chipped element is used as the series capacitor and the parallel inductor.