Scattered virtual antenna technology for wireless devices
A wireless device includes at least one radiating system having a redundancy system and a combining system. The redundancy system includes two or more radiation boosters. The radiating system is characterized by its simplicity that facilitates its integration within the wireless device and achieves enhanced radio-electric performance in at least one frequency region of the electromagnetic spectrum, which may include multiple wireless services. The combining system enables a substantially balanced power distribution among the radiation boosters of the redundancy system, and the radiating system provides an increased robustness to human loading effects in at least one frequency region of operation.
1. A wireless device comprising:
a radiating system included within the wireless device and configured to operate in a frequency region, the radiating system comprising:
an external port;
a redundancy system comprising: first and second radiation boosters each having a resonant frequency above a highest frequency of the frequency region, the first and second radiation boosters being substantially non-radiating for frequencies within the frequency region and being configured to contribute to the operation of the radiating system in the frequency region; a first internal port coupled to the first radiation booster, the first radiation booster featuring at the first internal port a first input impedance having a reactive component within the frequency region; a second internal port coupled to the second radiation booster, the second radiation booster featuring at the second internal port a second input impedance having a reactive component within the frequency region; and a ground plane layer; and
a combining system comprising: a first port connected to the first internal port of the redundancy system; a second port connected to the second internal port of the redundancy system; a third port connected to the external port of the radiating system; a first reactance cancellation element connected to the first port and configured to provide an impedance having an imaginary part substantially close to zero for a frequency within the frequency region; a second reactance cancellation element connected to the second port and configured to provide an impedance having an imaginary part substantially close to zero for a frequency within the frequency region; a first delay module configured to transform the first input impedance into a first impedance within the frequency region; and a second delay module configured to transform the second input impedance into a second impedance within the frequency region, the combining system combining the first and second input impedances into a combined impedance at the external port to produce a substantially balanced power distribution between the first and second radiation boosters, wherein the first impedance is out-of-phase with the second impedance by between 45° and 315° and an average resistance of the first impedance differs from an average resistance of the second impedance by less than 30%.
2. The apparatus of claim 1 , wherein the combining system further comprises a fine tuning circuit connected to the external port of the radiating system.
3. The apparatus of claim 1 , wherein the first radiation booster and the second radiation booster protrude beyond the ground plane layer.
4. The apparatus of claim 3 , wherein each of the first and second radiation boosters is located at a distance from a short edge of the ground plane layer that is less than 5% of the free-space wavelength corresponding to the lowest frequency of the frequency region.
5. The apparatus of claim 4 , wherein the first and second radiation boosters are located in opposite corners of a short edge of the ground plane layer.
6. The apparatus of claim 5 , wherein each of the first and second radiation boosters features a polyhedral shape comprising six faces.