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 radiating system configured to transmit and receive electromagnetic wave signals in at least a first frequency region, the radiating system comprising:
a ground plane layer including a connection point;
a radiation booster comprising a gap in the ground plane layer, the gap being delimited by at least three segments defining a curve, wherein a longest of the segments is less than 1/30 times a free-space wavelength corresponding to a lowest frequency of the first frequency region, the radiation booster including a connection point, a port being defined between the connection point of the ground plane layer and the connection point of the radiation booster; and
a radiofrequency system coupled to the port and including a matching network to transform an input impedance of the radiation system.
2. The radiating system of claim 1 , wherein: the at least three segments includes first and second segments located on opposite sides of the gap; the connection point of the radiation booster is on the first segment; and the connection point of ground plane layer is on the second segment.
3. The radiating system of claim 1 , wherein the ground plane layer has a perimeter including first and second edges, the first edge being longer than the second edge, and wherein the gap extends inward from the first edge.
4. The radiating system of claim 3 , wherein the gap is a substantially rectangular notch along the first edge.
5. The radiating system of claim 3 , wherein the gap is substantially centered with respect to the first edge.
6. The radiating system of claim 1 , wherein the ground plane layer has a perimeter including first and second edges, the first edge being longer than the second edge, and wherein the gap extends inward from the second edge.
7. The radiating system of claim 6 , wherein the gap is a substantially rectangular notch along the second edge.
8. The radiating system of claim 6 , wherein the gap is substantially centered with respect to the second edge.
9. The radiating system of claim 1 , wherein the gap is an elongated slot.
10. The radiating system of claim 9 , wherein the gap has a meandering shape delimited by at least ten segments, and wherein the ratio between the first resonance frequency of the radiating system at its port when disconnected from the radiofrequency system and the highest frequency of a first frequency region is larger than 3.
11. The radiating system of claim 9 , wherein the ground plane layer has a perimeter including an edge, and wherein the gap has a first end disposed at the edge of the perimeter and a second end disposed at an interior point in the ground plane layer.
12. The radiating system of claim 9 , wherein the gap has a U shape.
13. The radiating system of claim 12 , wherein the ground plane layer has a perimeter including an edge, and wherein the U-shaped gap has a first end disposed at the edge of the perimeter and a second end disposed at an interior point in the ground plane layer.
14. The radiating system of claim 12 , wherein the ground plane layer has a perimeter including first and second edges, the first edge being longer than the second edge, wherein the U-shaped gap extends inward from the first edge.
15. The radiating system of claim 1 , wherein the gap is disposed in an interior of the ground plane layer such that the at least three segments form a closed curve that does not intersect a perimeter of the ground plane layer.
16. The radiating system of claim 1 , wherein the gap comprises an inner gap and an outer gap separated by a conductive strip.
17. The radiation system of claim 1 , wherein the first frequency region includes the 824-960 MHz frequency range.
18. The radiation system of claim 1 , wherein the first frequency region includes the LTE frequency band.
19. The radiation system of claim 1 , wherein the LTE frequency band includes the 700 MHz frequency.
20. The radiation system of claim 1 , wherein the radiation booster is configured to operate at a second frequency region.
21. The radiation system of claim 20 , wherein the second frequency region includes the 1710-1890 MHz frequency range.