Electric field direction conversion structure and planar antenna

Patent metadata

Field	Value
Publication number	US-10158182-B2
Application number	US-201515501316-A
Country	US
Kind code	B2
Filing date	Mar 13, 2015
Priority date	Aug 18, 2014
Publication date	Dec 18, 2018
Grant date	Dec 18, 2018

Abstract

A first waveguide guides a first radio wave whose electric field is vibrated in a first direction along a second direction. A second waveguide guides the first radio wave along the second direction and is cascade connected to the first waveguide. An input and output end multiplexes the first radio waves from the first and second waveguides and outputs the multiplexed radio wave, and outputs the first radio wave branched off from a radio wave from outside to the first and second waveguides. A first waveguide shift portion is shifted from the first waveguide in the first direction. A second waveguide shift portion is shifted from the second waveguide in the first direction. The vibration directions of electric fields of radio waves passing through the end parts of the first and second waveguide shift portions are rotated by 90° about a third direction.

First claim

The invention claimed is:

1. A planar antenna comprising:
first to fourth antenna elements that are arranged in a grid on a plane that is vertical to a first direction, each of the first to fourth antenna elements combining a plurality of polarization waves and transmitting a polarization multiplexed signal or separating a polarization multiplexed signal that has been received into a plurality of polarization waves;
a first waveguide part configured to output a second radio wave to the first to fourth antenna elements or receives the second radio wave that has been separated by the first to fourth antenna elements; and
a second waveguide part configured to output a third radio wave having an electric field whose vibration direction is vertical to the vibration direction of the electric field of the second radio wave to the first to fourth antenna elements or receives the third radio wave separated by the first to fourth antenna elements, wherein
the first waveguide part comprises:
an electric field direction conversion structure comprising:
a first waveguide configured to guide a first radio wave whose electric field is vibrated in the first direction along a second direction that is vertical to the first direction between a first end part and a second end part;
a second waveguide configured to guide the first radio wave along the second direction between a third end part and a fourth end part, the second waveguide being cascade connected to the first waveguide by a connection of the first end part and the third end part;
an input and output end configured to multiplex the first radio wave from the first waveguide and the first radio wave from the second waveguide and outputs the multiplexed radio wave, and outputs the first radio wave branched off from a radio wave from outside to the first and second waveguides at a connection portion between the first end part and the third end part;
a first waveguide shift portion having a fifth end part connected to the second end part of the first waveguide and a sixth end part that is shifted from the fifth end part in the first direction, the second radio wave having an electric field vibrated in the second direction being input or output to or from the sixth end part along the second direction; and
a second waveguide shift portion having a seventh end part connected to the fourth end part of the second waveguide and an eighth end part that is shifted from the seventh end part in the first direction and in a direction opposite to the sixth end part, the second radio wave having an electric field vibrated in the second direction being input or output to or from the eighth end part along the second direction;

a third waveguide having one end connected to the first antenna element and another end connected to the second antenna element, the center of the third waveguide being connected to the sixth end part, and the third waveguide extending in a third direction that is vertical to the first and second directions; and
a fourth waveguide having one end connected to the third antenna element and another end connected to the fourth antenna element, the center of the fourth waveguide being connected to the eighth end part, and the fourth waveguide extending in the third direction,

a vibration direction of an electric field of a radio wave passing through the sixth end part of the first waveguide shift portion is rotated by 90° about the third direction,
a vibration direction of an electric field of a radio wave passing through the eighth end part of the second waveguide shift portion is rotated by 90° about the third direction in a direction the same as the rotational direction in the sixth end part,
the vibration direction of the electric field of the third radio wave is vertical to the vibration direction of the electric field of the first radio wave,
the first waveguide shift portion is formed of a curved waveguide that connects the fifth end part and the sixth end part, and
the second waveguide shift portion is formed of a curved waveguide that connects the seventh end part and the eighth end part.

2. The planar antenna according to claim 1 , wherein the center axis of the waveguide that constitutes the first waveguide shift portion and the second waveguide shift portion is the second direction, and the waveguide has a step-like shape and is shifted in a step-like manner along the first direction.

3. The planar antenna according to claim 1 , wherein the distance between the input and output end and the sixth end part is equal to the distance between the input and output end and the eighth end part.

4. The planar antenna according to claim 1 , wherein the distance between the center of the third waveguide and the first antenna element, the distance between the center of the third waveguide and the second antenna element, the distance between the center of the fourth waveguide and the third antenna element, and the distance between the center of the fourth waveguide and the fourth antenna element are equal to one another.

5. The planar antenna according to claim 1 , wherein
the first to fourth antenna elements each comprise:
a polarization wave separation/combination portion configured to separate the second radio wave and the third radio wave included in the polarization multiplexed signal or combines the second radio wave and the third radio wave into the polarization multiplexed signal;
a horn antenna portion configured to transmit the polarization multiplexed signal from the polarization wave separation/combination portion or transmits the polarization multiplexed signal that has been received to the polarization wave separation/combination portion, and
the polarization wave separation/combination portion receives or outputs the second radio wave through an opening on a plane vertical to the third direction and receives or outputs the third radio wave through an opening on a bottom surface vertical to the first direction.

6. The planar antenna according to claim 5 , wherein
the second waveguide part is connected to the opening on the bottom surface of the polarization wave separation/combination portion of each of the first to fourth antenna elements, and
the second waveguide part converts the third radio wave from the opening on the bottom surface of the polarization wave separation/combination portion of each of the first to fourth antenna elements into the first radio wave, combines the resulting radio waves in phase with each other, and outputs the combined radio wave or separates the first radio wave input from outside to convert the first radio wave into the third radio wave and guides the third radio wave after the conversion to the opening on the bottom surface of the polarization wave separation/combination portion of each of the first to fourth antenna elements in the same phase.

7. The planar antenna according to claim 1 , wherein the first waveguide part and the second waveguide part are formed in different layers laminated to each other in the first direction.

8. A planar antenna comprising:
a plurality of antenna elements arranged on a first plane;
a first waveguide part configured to receive or outputs a first radio wave from or to the plurality of antenna elements, the first radio wave being used for orthogonal polarization transmission; and
a second waveguide part configured to receive or outputs a second radio wave whose polarization plane is perpendicular to the polarization plane of the first radio wave from or to the plurality of antenna elements, wherein
the first waveguide part and the second waveguide part are laminated to each other substantially parallel to the first plane,
the first waveguide part comprises an electric field direction conversion portion having a fi

Assignees

• Nec Corp

Inventors

• Iwanaka Daisuke

Classifications

• H01P5/20

  Magic-T junctions · CPC title

• H01Q15/246

  rotating the plane of polarisation of a linear polarised wave (guided wave H01P1/165) · CPC title

• H01P5/12 Primary

  Coupling devices having more than two ports (H01P5/04 takes precedence) · CPC title

• H01Q21/0006

  Particular feeding systems · CPC title

• H01Q21/24 Primary

  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 title