Antenna unit

1. Hearing device comprising

a hearing device housing configured to be positioned at an ear of a person, and

an antenna unit arranged in the housing, the antenna unit including a first plane surface of a first plate having a first perimeter part along an outer circumference of the first plate and a second plane surface of a second plate having a second perimeter part along an outer circumference of the second plate, the first and second perimeter parts of the first and second plates together form a slot antenna, wherein

the first plate is physically separate from the second plate;

the first plate and the second plate are arranged such that an angle between a normal pointing outwards from the first plane surface of the first plate and a normal pointing outwards from the second plane surface of the second plate is greater than zero, and

the slot is arranged at a corner of the housing.

2. Hearing device comprising

a hearing device housing configured to be positioned at an ear of a person, and

an antenna unit arranged in the housing, the antenna unit including a first plane surface of a first plate having a first perimeter part along an outer circumference of the first plate and a second plane surface of a second plate having a second perimeter part along an outer circumference of the second plate, the first and second perimeter parts of the first and second plates together form a slot antenna, wherein

the first plate is physically separate from the second plate;

the first plate and the second plate are arranged such that an angle between a normal pointing outwards from the first plane surface of the first plate and a normal pointing outwards from the second plane surface of the second plate is greater than zero, and

during use the electric field emitted from the slot is perpendicular or near perpendicular to the ear-to-ear axis of the person wearing the hearing device.

3. Hearing device configured to be worn at an ear of a person, the hearing device comprising

a hearing device housing configured to be positioned at an ear of a person, and

an antenna unit, the antenna unit including a first part and a second part forming a radiating structure, and

an antenna feed that feeds the antenna unit with an electrical signal, wherein

the first plate of the radiating structure has a first perimeter part along an outer circumference of the first plate,

the second plate of the radiating structure has a second perimeter part along an outer circumference of the first plate,

the first perimeter part and the second perimeter part are arranged in the housing so as to define part of a slot, the slot defining a slot plane where an electrical field component of an emitted electromagnetic field at the slot is parallel to the slot plane,

the first plate is physically separate from the second plate;

the first plate and the second plate are arranged such that an angle between a surface normal pointing outwards from the first plate and a surface normal pointing outwards from the second plate is greater than zero, and

the antenna unit is arranged in the housing such that when the housing is worn by a person a normal of the slot plane has a direction in the interval 10 to 90 degrees relative to an ear-to-ear axis of the user.

4. The hearing device according to claim 3 , wherein the angle between the surface normal of the first and second plates is 45 degrees or 90 degrees.

5. The hearing device according to claim 3 , wherein the first plate has a first plane surface and the second plate has a second plane surface, where the first plane surface and the second plane surface are displaced relative to each other in a direction parallel to the surface normal.

6. The hearing device according to claim 5 , wherein when the housing is worn by the person the normal of the slot plane has a direction which is in the interval 30 to 70 degrees, in the interval 40 to 60 degrees, 45 degrees, or 90 degrees.

7. The hearing device according claim 3 , wherein the first perimeter part and the second perimeter part are arranged so that the geometric minimum distance between them is substantially constant along the length of the slot.

8. The hearing device according to claim 3 , wherein the first perimeter part and the second perimeter part are straight lines and the first perimeter part and the second perimeter part are arranged so that the lines are parallel.

9. The hearing device according to claim 3 , wherein

the first plate has a first electrically conductive material provided as a sheet on a substrate,

the second plate has a second electrically conductive material provided as a sheet on a substrate, and

the first electrical conductive material comprises two parts electrically interconnected and the parts are arranged so as to form a structure having a bend defined at the intersection of the two parts.

10. The hearing device according to claim 3 , wherein

the first plate has a first electrically conductive material provided as a sheet on a substrate,

the second plate has a second electrically conductive material provided as a sheet on a substrate, and

the first electrically conductive material when used in the housing is arranged at a top part of the housing, and the second electrically conductive material is arranged at a side of the housing.

11. The hearing device according to claim 3 , wherein the antenna unit with the slot forms a resonant structure when the antenna unit is loaded by the presence of a head or in free space.

12. The hearing device according to claim 3 , wherein the slot comprises an opening configured to receive a battery and/or an audio converter and/or an input device.

13. The hearing device according to claim 3 , wherein the slot comprises two or more areas having non-conductive surfaces forming a combined slot.

14. The hearing device according to claim 3 , wherein the antenna unit is formed on or by one or more flex circuit boards and the slot is formed by one or more areas of electrically non-conductive material surrounded by electrically conductive material.

15. The hearing device according to claim 3 wherein the hearing device further comprises:

an audio converter for reception of an acoustic signal and conversion of the received acoustic signal into a corresponding electrical audio signal,

a signal processor for processing the electrical audio signal into a processed audio signal so as to compensate a hearing loss of a user of the hearing aid,

a transducer connected to an output of the signal processor for converting the processed audio signal into an output signal, and

a transceiver for wireless data communication, wherein the transceiver is connected to the antenna unit adapted for electromagnetic field emission and/or electromagnetic field reception, and

the housing is configured to be positioned behind the ear of the user.

16. The hearing device according to claim 3 , wherein at least electronic components of the hearing device is arranged within a space defined at least partly by the radiating structure.

17. The hearing device according to claim 3 , wherein the antenna unit is configured to have an operation frequency in the range of 1 to 10 GHz, such as around 2.4 GHz, such as around 5.2 GHz.

18. Use of a hearing device according to claim 1 for communicating with a hand held device.

19. Use according to claim 18 , wherein the hand held device is a mobile phone, and a voice signal from the mobile phone is presented to the user via the hearing device.

20. The hearing device according to claim 1 , wherein the slot extends along, or parallel to, a longitudinal axis of the hearing device.

21. The hearing device according to claim 2 , wherein the slot is open ended.