Circularly polarized antenna and rectenna using this antenna

• US 7,079,080 B2
• Filed: 10/25/2004
• Issued: 07/18/2006
• Est. Priority Date: 05/24/2004
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Mizuno, Tomohiro, Satoh, Hiroyuki, Okegawa, Hirokatsu
• Primary Examiner(s): Nguyen, Hoang V.
• Application Number:
  US10/971,141
• Publication Number:
  US 20050259030A1
• Time in Patent Office: 631 Days
• Field of Search: 343/700.MS, 343/866, 343/867, 343/850, 343/865, 343/741
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 1/248 provided with an AC/DC converting device, e.g. rectennas
• 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 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Abstract

A loop antenna unit (2), a balanced line (3), and two perturbation elements (4) are formed on a dielectric board (1) by using manufacturing methods, such as printing and etching. The loop antenna unit (2) is formed along the circumference of a circle, and is connected to the balanced line (3). Each of the two perturbation elements (4) is a member in the shape of a tooth which is inclined 45 degrees against a direction of feeding of power via the balanced line (3) and which is projecting from the loop antenna unit (2) in an inward direction toward the center of the loop antenna unit (2). The two perturbation elements (4) are arranged at two opposite points in the loop antenna unit (2) so that they are opposite to each other.

Claims

1. A circularly polarized antenna comprising:

a dielectric board having first and second opposite surfaces;

a balanced line formed on a first surface of said dielectric board;

a loop antenna unit disposed on the first surface of said dielectric board, formed in a shape of a loop, and connected to said balanced line; and

two perturbation elements each of which is formed in a shape of a tooth and is projecting from said loop antenna unit in an inward direction toward a center of said loop antenna unit, said two perturbation elements being arranged opposite to each other,

wherein no ground plate is formed on the second surface of the dielectric board.

2. The circularly polarized antenna according to claim 1, wherein each of said two perturbation elements is shaped like a crank.

3. The circularly polarized antenna according to claim 1, wherein said dielectric board is a thin-film board.

4. The circularly polarized antenna according to claim 1, further comprising two other perturbation elements each of which is formed in a shape of a crank and is projecting from said loop antenna unit in an outward direction, said two other perturbation elements being arranged opposite to each other.

5. A circularly polarized antenna comprising:

a dielectric board having first and second opposite surfaces;

a balanced line formed on a first surface of said dielectric board;

a loop antenna unit disposed on the first surface of said dielectric board, formed in a shape of a loop, and connected to said balanced line; and

two perturbation elements each of which is formed in a shape of a crank and is projecting from said loop antenna unit in an outward direction, said two perturbation elements being arranged opposite to each others,

wherein no ground plate is formed on the second surface of the dielectric board.

6. A rectenna element comprising:

a dielectric board;

a loop antenna unit disposed on said dielectric board and formed in a shape of a loop;

two perturbation elements disposed in said loop antenna unit so that they are opposite to each other; and

a rectifier circuit disposed on said dielectric board, for rectifying RF electric power received by said loop antenna unit.

7. The rectenna element according to claim 6, wherein said dielectric board is a thin-film board.

8. A rectenna comprising:

a dielectric board;

a plurality of rectenna elements each including a loop antenna unit disposed on said dielectric board and formed in a shape of a loop, two perturbation elements disposed in said loop antenna unit so that they are opposite to each other, and a rectifier circuit disposed on said dielectric board, for rectifying RF electric power received by said loop antenna unit; and

a combining circuit having a strip line that connects positive inputs of the rectifier circuits of said plurality of rectenna elements with one another, and another strip line that connects negative inputs of the rectifier circuits of said plurality of rectenna elements with one another, for connecting said plurality of rectenna elements in parallel with one another.

9. A rectenna comprising:

a dielectric board;

a plurality of rectenna elements each including a loop antenna unit disposed on said dielectric board and formed in a shape of a loop, two perturbation elements disposed in said loop antenna unit so that they are opposite to each other, and a rectifier circuit disposed on said dielectric board, for rectifying RF electric power received by said loop antenna unit; and

a combining circuit for connecting the rectifier circuits of said plurality of rectenna elements in series.

10. A circularly polarized antenna comprising:

a dielectric board;

a balanced line formed on a surface of said dielectric board;

a loop antenna unit disposed on the surface of said dielectric board, formed in a shape of a loop, and connected to said balanced line;

two perturbation elements each of which is formed in a shape of a tooth and is projecting from said loop antenna unit in an inward direction toward a center of said loop antenna unit, said two perturbation elements being arranged opposite to each other; and

two other perturbation elements each of which is formed in a shape of a crank and is projecting from said loop antenna unit in an outward direction, said two other perturbation elements being arranged opposite to each other.

11. The circularly polarized antenna according to claim 10, wherein each of said two perturbation elements is shaped like a crank.

12. The circularly polarized antenna according to claim 10, wherein said dielectric board is a thin-film board.