Antennaless wireless device
A radiating system of a wireless device transmits and receives electromagnetic wave signals in a frequency region and comprises an external port, a radiating structure, and a radiofrequency system. The radiating structure includes: a ground plane layer with a connection point; a radiation booster with a connection point and being smaller than 1/30 of a free-space wavelength corresponding to a lowest frequency of the frequency region; and an internal port between the radiation booster connection point and the ground plane layer connection point. The radiofrequency system includes: a first port connected to the radiating structure's internal port; and a second port connected to the external port. An input impedance at radiating structure's disconnected internal port has a non-zero imaginary part across the frequency region. The radiofrequency system modifies impedance of the radiating structure to provide impedance matching to the radiating system within the frequency region at the external port.
1. A wireless device comprising:
a radiating system configured to transmit and receive electromagnetic wave signals in a first frequency region, the radiating system comprising:
an external port;
a radiating structure comprising:
a ground plane layer including a connection point;
a radiation booster including a connection point and having a maximum size smaller than 1/30 times a free-space wavelength corresponding to a lowest frequency of the first frequency region; and
an internal port defined between the connection point of the radiation booster and the connection point of the ground plane layer; and
a radiofrequency system comprising:
a first port connected to the internal port of the radiating structure; and
a second port connected to the external port;
wherein an input impedance of the radiating structure at the internal port, when disconnected from the radiofrequency system, has an imaginary part not equal to zero for any frequency of the first frequency region; and
wherein the radiofrequency system modifies impedance of the radiating structure to provide impedance matching to the radiating system within the first frequency region at the external port.
2. The wireless device according to claim 1 , wherein:
a ground plane rectangle is defined as being a minimum-sized rectangle that encompasses the ground plane layer, so that sides of the ground plane rectangle are tangent to at least one point of the ground plane layer; and
a ratio between a side of the ground plane rectangle and the free-space wavelength corresponding to the lowest frequency of the first frequency region is greater than 0.1.
3. The wireless device according to claim 1 , wherein:
the radiating structure, when disconnected from the radiofrequency system, has a first resonance frequency measured at the internal port; and
a ratio between said first resonance frequency and a highest frequency of the first frequency region is greater than 3.
4. The wireless device according to claim 1 , wherein the first frequency region comprises an 824-960 MHz frequency range.
5. A wireless device comprising:
a radiating system configured to transmit and receive electromagnetic wave signals in a first frequency region, the radiating system comprising:
an external port;
a radiating structure comprising:
a ground plane layer including a connection point;
a radiation booster configured to contribute to exciting, on the ground plane layer, at least one radiation mode that occurs at a frequency higher than a lowest frequency of the first frequency region, the radiation booster including a connection point, wherein a height of the radiation booster with respect to the ground plane layer is less than 2% of a free-space wavelength corresponding to the lowest frequency of the first frequency region; and
an internal port defined between the connection point of the radiation booster and the connection point of the ground plane layer; and
a radiofrequency system comprising:
a first port connected to the internal port of the radiating structure; and
a second port connected to the external port;
wherein an input impedance of the radiating structure at the internal port, when disconnected from the radiofrequency system, has an imaginary part not equal to zero for any frequency of the first frequency region; and
wherein the radiofrequency system modifies impedance of the radiating structure to provide impedance matching to the radiating system within the first frequency region at the external port.
6. The wireless device according to claim 5 , wherein the first frequency region comprises an 824-960 MHz frequency range.
7. The wireless device according to claim 5 , wherein the radiation booster is at a distance from the ground plane layer less than 5% of the free-space wavelength corresponding to the lowest frequency of the first frequency region.
8. The wireless device according to claim 7 , wherein:
a ground plane rectangle is defined as being a minimum-sized rectangle that encompasses the ground plane layer, so that sides of the ground plane rectangle are tangent to at least one point of the ground plane layer; and
a ratio between a side of the ground plane rectangle and the free-space wavelength corresponding to the lowest frequency of the first frequency region is greater than 0.1.
9. The wireless device according to claim 5 , wherein:
a booster box is defined as being a minimum-sized parallelepiped of square or rectangular faces that completely encloses the radiation booster and wherein each one of the faces of said minimum-sized parallelepiped is tangent to at least a point of said radiation booster and each possible pair of faces of said minimum-sized parallelepiped sharing an edge forms an inner angle of 90°; and
a smallest dimension of the booster box is smaller than 70% of a largest dimension of the booster box.
10. The wireless device according to claim 9 , wherein the smallest dimension of the booster box is smaller than 20% of the largest dimension of the booster box.
11. The wireless device according to claim 5 , wherein:
the radiating structure, when disconnected from the radiofrequency system, has a first resonance frequency measured at the internal port; and
a ratio between said first resonance frequency and a highest frequency of the first frequency region is greater than 3.
12. The wireless device according to claim 5 , wherein the radiation booster has a maximum size smaller than 1/50 times the free-space wavelength corresponding to the lowest frequency of the first frequency region.
13. A wireless device comprising:
a radiating system configured to transmit and receive electromagnetic wave signals in a first frequency region, the radiating system comprising:
an external port;
a radiating structure comprising:
a ground plane layer;
a radiation booster configured to contribute to exciting, on the ground plane layer, at least one radiation mode; and
an internal port defined between a connection point of the radiation booster and a connection point of the ground plane layer; and
a radiofrequency system comprising:
a first port connected to the internal port of the radiating structure; and
a second port connected to the external port;
wherein a booster box is defined as being a minimum-sized parallelepiped of square or rectangular faces that completely encloses the radiation booster and wherein each one of the faces of said minimum-sized parallelepiped is tangent to at least a point of said radiation booster and each possible pair of faces of said minimum-sized parallelepiped sharing an edge forms an inner angle of 90°;
wherein a smallest dimension of the booster box is smaller than 70% of a largest dimension of the booster box;
wherein an input impedance of the radiating structure at the internal port, when disconnected from the radiofrequency system, has an imaginary part not equal to zero for any frequency of the first frequency region; and
wherein the radiofrequency system modifies impedance of the radiating structure to provide impedance matching to the radiating system, at the external port, within the first frequency region.
14. The wireless device according to claim 13 , wherein the smallest dimension of the booster box is smaller than 20% of the largest dimension of the booster box.
15. The wireless device according to claim 13 , wherein the largest dimension of the booster box is smaller than 1/30 times a free-space wavelength corresponding to a lowest frequency of the first frequency region.
16. The wireless device according to claim 15 , wherein the largest dimension of the booster box is smaller than 1/50 times a free-space wavelength corresponding to the lowest frequency of the first frequency region.
17. The wireless device according to claim 13 , wherein the first frequency region comprises an 824-960 MHz frequency range.
18. The wireless device according to claim 13 , wherein a ratio between a first resonance frequency of the radiating structure measured at the internal port when disconnected from the radiofrequency system and a highest frequency of the first frequency region is greater than 3.
19. The wireless device according to claim 13 , wherein:
a ground plane rectangle is defined as being a minimum-sized rectangle that encompasses the ground plane layer, so that sides of the ground plane rectangle are tangent to at least one point of the ground plane layer; and
a ratio between a side of the ground plane rectangle and the free-space wavelength corresponding to the lowest frequency of the first frequency region is greater than 0.1.
20. The wireless device according to claim 13 , wherein the radiation booster comprises a conductive strip.