Antennaless wireless device capable of operation in multiple frequency regions
The present invention refers to an antenna less wireless handheld or portable device comprising a communication module including a radiating system capable of transmitting and receiving electromagnetic wave signals in a first frequency region and in a second frequency region, wherein the highest frequency of the first frequency region is lower than the lowest frequency of the second frequency region. The radiating system comprising a radiating structure and at least one internal port, wherein the input impedance of the radiating structure at the/each 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 said radiofrequency system modifies the impedance of the radiating structure, providing impedance matching to the radiating system in the at least two frequency regions of operation of the radiating system.
1. A radiation system comprising:
a ground plane layer;
a radiation booster comprising:
a conductive part including at least one conducting polygonal shape with four or more sides; and
a connection point located substantially close to a corner of the conductive part, the radiation booster being configured to operate in at least first and second frequency regions of the electromagnetic spectrum and fitting inside a booster box with a maximum dimension smaller than 1/30 the free-space wavelength corresponding to a lowest frequency of a lowest frequency region of operation so that the radiation booster behaves as a non-radiating element at least at said lowest frequency while transferring radiation energy to the ground plane layer;
a connection point on the ground plane layer, the connection point defining, together with a connection point located on the radiation booster, an internal port;
a radiofrequency system including a matching network to transform the input impedance of the radiating structure; and
an external port,
wherein the first frequency region includes or is contained within the frequency range 824-960 MHz, and wherein the second frequency region includes or is contained in the frequency range 1710-2170 MHz.
2. The radiation system according to claim 1 , wherein the radiation booster further comprises a conductive part mounted on a polyhedral shape comprising a plurality of faces, the conductive part comprising two polygonal faces and at least one conductive strip.
3. The radiation system according to claim 2 , wherein the at least one conductive strip is printed on a gap on the polyhedral shape.
4. The radiation system according to claim 2 , wherein:
the radiation booster is configured to be mounted on a layer supporting the ground plane layer; and
a height of the radiation booster with respect to the ground plane layer is less than 2% of the free-space wavelength corresponding to the lowest frequency of the lowest frequency region of operation of the radiation booster.
5. The radiation system according to claim 2 , wherein the conductive part comprises two conductive strips.
6. The radiation system according to claim 5 , wherein the conductive part comprises four conductive strips.
7. The radiation system according to claim 5 , wherein the radiation booster has a maximum size less than 1/50 times a free-space wavelength corresponding to the lowest frequency of the lowest frequency region of operation of the radiation booster.
8. A wireless device comprising the radiation system according to claim 5 , wherein:
a ratio between a first resonance frequency at the first internal port of the radiating structure, when disconnected from the radiofrequency system, and a highest frequency of the first frequency region is greater than three; and
a ratio between a first resonance frequency at the second internal port of the radiating structure, when disconnected from the radiofrequency system, and the highest frequency of the first frequency region is greater than three.
9. The wireless device according to claim 8 , wherein the radiation booster is located proximate to said corner of the ground plane layer.
10. The wireless device according to claim 9 , comprising a second radiation booster located proximate to a second corner of the ground plane layer.
11. The wireless device according to claim 9 , comprising a third radiation booster located proximate to a third corner of the ground plane layer.
12. The wireless device according to claim 9 , wherein the wireless device is a mobile phone.
13. The wireless device according to claim 9 , wherein the wireless device is a smartphone.
14. A wireless device comprising the radiation system according to claim 1 , wherein:
a ratio between a first resonance frequency at the first internal port of the radiating structure, when disconnected from the radiofrequency system, and a highest frequency of the first frequency region is greater than three; and
a ratio between a first resonance frequency at the second internal port of the radiating structure, when disconnected from the radiofrequency system, and the highest frequency of the first frequency region is greater than three.
15. The wireless device according to claim 14 , wherein the radiation booster is located proximate to said corner of the ground plane layer.
16. The wireless device according to claim 15 , comprising a second radiation booster located proximate to a second corner of the ground plane layer.
17. The wireless device according to claim 16 , comprising a third radiation booster located proximate to a third corner of the ground plane layer.
18. The wireless device according to claim 15 , wherein the wireless device is a mobile phone.
19. The wireless device according to claim 15 , wherein the wireless device is a smartphone.
20. The wireless device according to claim 15 , wherein the wireless device is a tablet.