Array antenna
Disclosed is an antenna, in particular array antenna. The antenna includes an antenna top surface ( 1 a ) and an antenna bottom surface ( 1 b ). The antenna further includes a waveguide channel structure with a plurality of waveguide end branches ( 111 ). Each waveguide end branch ( 111 ) opens into an associated waveguide opening ( 100 ) in the antenna top surface ( 1 a ) in a one-to-one relation, wherein the waveguide openings ( 100 ) are arranged in a pattern of rows and columns. A plurality of recesses ( 101 ) extends from the antenna top surface ( 1 a ) towards the antenna bottom surface ( 1 b ), the plurality of recesses ( 101, 101 b ) being arranged such that a recess ( 101 b ) is present between pairs of neighboring waveguide openings ( 100 ) of the same row and/or column.
1. An antenna comprising:
an antenna top surface ( 1 a ) and an antenna bottom surface ( 1 b ), wherein the antenna includes a waveguide channel structure with a plurality of waveguide end branches ( 111 ), wherein each waveguide end branch ( 111 ) opens into an associated waveguide opening ( 100 ) in the antenna top surface ( 1 a ) in a one-to-one relation, wherein the waveguide openings ( 100 ) are arranged in a pattern of rows and columns, and wherein a plurality of recesses ( 101 , 101 b ) extend from the antenna top surface ( 1 a ) towards the antenna bottom surface ( 1 b ), the plurality of recesses ( 101 , 101 b ) being arranged such that a recess ( 101 , 101 b ) is present between pairs of neighbouring waveguide openings ( 100 ) of the same row and/or column;
wherein the waveguide channel structure opens into a plurality of waveguide terminal openings ( 130 ) in the antenna bottom surface ( 1 b ) and the waveguide channel structure extends between the antenna top surface ( 1 a ) and the antenna bottom surface ( 1 b ), the waveguide channel structure coupling the waveguide openings ( 100 ) and the waveguide terminal openings ( 130 ); and
wherein the number of waveguide terminal openings ( 130 ) corresponds to the number of rows and wherein the waveguide channel structure couples each waveguide terminal opening ( 130 ) with all waveguide openings ( 100 ) of a corresponding row and independent from the other rows.
2. The antenna according to claim 1 , wherein the recesses are elongated channels ( 101 ) that extend traverse to the rows and/or columns.
3. The antenna according to claim 2 , wherein the channels ( 101 ) extend beyond outermost rows and/or columns.
4. The antenna according to claim 2 , wherein a channel depth varies periodically along the channel length.
5. The antenna according to claim 2 , wherein a channel width varies periodically along the channel length.
6. The antenna according to claim 1 , wherein a separate recess ( 101 b ) is provided in each row between neighbouring columns and/or in each column between neighbouring rows.
7. The antenna according to claim 1 , wherein a recess depth is between ⅛ and ⅜ of the wavelength in an operational frequency range of the antenna.
8. The antenna according to claim 1 , wherein the antenna is made from stacked coplanar layers ( 10 , 11 , 12 , 13 ), with the antenna top surface ( 1 a ) belonging to a top layer ( 10 ) and the antenna bottom surface ( 1 b ) belonging to the bottom layer ( 13 ).
9. The antenna according to claim 1 , wherein the antenna is made from metal and/or metalized plastics and/or conductive plastics.
10. The antenna of claim 1 comprising an array antenna.
11. An antenna comprising:
an antenna top surface ( 1 a ) and an antenna bottom surface ( 1 b ), wherein the antenna includes a waveguide channel structure that opens into a plurality of waveguide openings ( 100 ) in the antenna top surface ( 1 a ), the waveguide openings ( 100 ) being arranged in a pattern of rows and columns, wherein the antenna includes a top layer ( 10 ) with the antenna top surface ( 1 a ) belonging to the top layer ( 10 ), wherein the top layer ( 10 ) is made from partially metallized non-conductive material, and a non-metalized area is present on the antenna top surface ( 1 a ) between neighbouring waveguide openings ( 100 ) of the same row and/or column;
wherein the waveguide channel structure opens into a plurality of waveguide terminal openings ( 130 ) in the antenna bottom surface ( 1 b ) and the waveguide channel structure extends between the antenna top surface ( 1 a ) and the antenna bottom surface ( 1 b ), the waveguide channel structure coupling the waveguide openings ( 100 ) and the waveguide terminal openings ( 130 ); and
wherein the number of waveguide terminal openings ( 130 ) corresponds to the number of rows and wherein the waveguide channel structure couples each waveguide terminal opening ( 130 ) with all waveguide openings ( 100 ) of a corresponding row and independent from the other rows.
12. The antenna according to claim 11 , wherein the top surface is metalized in an area around the waveguide openings ( 100 ) and a plurality of non-metalized stripes are present on the antenna top surface ( 1 a ) such that a non-metalized strip extends between neighbouring rows and/or columns.
13. The antenna according to claim 11 , wherein the antenna top surface ( 1 a ) is non-metalized over a whole area that is covered by the waveguide openings ( 100 ).
14. The antenna of claim 11 comprising an array antenna.