Cavity supported patch antenna
An antenna ( 100 ) comprises a cavity ( 120 ) formed by a conductive plate ( 121 ) in a first horizontal conductive layer ( 221 ) of a multi-layer circuit board and a vertical sidewall formed by conductive vias ( 222 ) extending from the conductive plate ( 121 ). Further, the antenna ( 100 ) comprises an antenna patch ( 130 ) arranged in the cavity. The antenna patch ( 130 ) is formed in a second conductive layer ( 223 ) of the multi-layer circuit board and is peripherally surrounded by the vertical sidewall of the cavity ( 120 ).
1. An antenna, comprising:
a cavity formed by a conductive plate in a first horizontal conductive layer of a multi-layer circuit board and a vertical sidewall formed by conductive vias extending from the conductive plate;
an antenna patch arranged in the cavity, the antenna patch being formed in a second conductive layer of the multi-layer circuit board and being peripherally surrounded by the vertical sidewall of the cavity; and
a parasitic patch arranged in a plane which is parallel to the antenna patch, wherein the parasitic patch is vertically offset from the antenna patch towards a third horizontal conductive layer, is horizontally offset with respect to the antenna patch, and has a different shape than the antenna patch.
2. The antenna according to claim 1 ,
wherein the conductive vias extend from the conductive plate to the third horizontal conductive layer of the multi-layer circuit board.
3. The antenna according to claim 2 ,
wherein the cavity further comprises a conductive frame which is formed in the third horizontal conductive layer and conductively connects the conductive vias of the vertical sidewall.
4. The antenna according to claim 1 ,
wherein the parasitic patch is formed in the third horizontal conductive layer.
5. The antenna according to claim 1 ,
wherein the parasitic patch is horizontally centered with respect to the antenna patch.
6. The antenna according to claim 1 , comprising:
at least one feed connection extending through the conductive plate to a feed point on the antenna patch.
7. The antenna according to claim 1 , comprising:
a first feed connection extending through the conductive plate to a first feed point on the antenna patch; and
a second feed connection extending through the conductive plate to a second feed point on the antenna patch.
8. The antenna according to claim 7 ,
wherein the first feed point is offset from a center of the antenna patch in a first horizontal direction corresponding to a first polarization direction of the antenna, and
wherein the second feed point is offset from a center of the antenna patch in a second horizontal direction corresponding to a second polarization direction of the antenna.
9. The antenna according to claim 1 , comprising:
multiple cavities, each formed by a conductive plate in the first horizontal conductive layer of the multi-layer circuit board and a vertical sidewall formed by conductive vias extending from the conductive plate;
multiple antenna patches, each arranged in a respective one of the cavities, the antenna patches being formed in the second conductive layer of the multi-layer circuit board and being peripherally surrounded by the vertical sidewall of the respective cavity.
10. The antenna according to claim 1 ,
wherein the antenna is configured for transmission of radio signals having a wavelength of more than 1 mm and less than 3 cm.
11. A communication device, comprising:
at least one antenna according to claim 1 ; and
at least one processor configured to process communication signals transmitted via the at least one antenna.
12. The communication device according to claim 11 , comprising:
radio front end circuitry arranged on the multi-layer circuit board.