Quad-band tunable diversity antenna for global applications
An electronic device includes a main antenna and a diversity antenna. The diversity antenna includes a first portion configured to enable a transceiver to receive a signal in a first low-band frequency of four frequency bands. A second portion enables the transceiver to receive a signal in first and second high-band frequencies. A third portion is RF coupled to the first portion when the third portion is connected to ground. The third portion tunes the first portion such that the transceiver receives a signal in a second low-band frequency. A switch is connected between the third portion and the ground. When the switch is open, the first portion enables the transceiver to receive the signal in the first low-band frequency. When the switch is closed, the third portion tunes the first portion to enable the transceiver to receive the signal in the second low-band frequency.
1. An electronic device, comprising:
a housing;
a wireless transceiver disposed within the housing;
a main antenna coupled to the transceiver and configured to enable the transceiver to operate in at least four wireless frequency bands; and
a diversity antenna coupled to the transceiver, the diversity antenna configured to receive signals in at least the four wireless frequency bands and configured as an inverted F-antenna, the diversity antenna comprising:
a first portion having a first end and a second end, the first portion configured to enable the transceiver to receive a signal in a first low-band frequency of the four frequency bands;
a second portion connected to the first end of the first portion, the second portion configured to enable the transceiver to receive signals in first and second high-band frequencies of the four frequency bands;
a third portion RF coupled to the first portion when the third portion is connected to ground, the third portion configured to tune the first portion such that the transceiver receives a signal in a second low-band frequency of the four frequency bands; and
a switch connected between the third portion and the ground, wherein when the switch is open, the first portion enables the transceiver to receive the signal in the first low-band frequency, and wherein when the switch is closed, the third portion tunes the first portion to enable the transceiver to receive the signal in the second low-band frequency.
2. The electronic device of claim 1 , wherein the first high-band frequency is in a 2100 MHz frequency band, the second high-band frequency is in a 1900 MHz frequency band, the first low-band frequency is in a 850 MHz frequency band, and the second low-band frequency is in a 700 MHz frequency band.
3. The electronic device of claim 1 , wherein the third portion extends from a first end to a second end in which the first end of the third portion is substantially adjacent to the second end of the first portion.
4. The electronic device of claim 3 , wherein a disposition of the first end of the third portion relative to the second end of the first portion generates a highest radio frequency (RF) voltage.
5. The electronic device of claim 1 , further comprising:
a printed circuit board (PCB) comprising;
a feed connected to the first portion;
a first ground connected to the first portion; and
a second ground connected to the third portion through the switch.
6. The electronic device of claim 1 , wherein the first portion and the third portion are separated by a gap, wherein the first portion and the third portion are RF coupled when the third portion is connected to the ground.
7. The electronic device of claim 6 , wherein the third portion tunes the first low-band frequency of the first portion in a predetermined manner as a function of the gap and a length of the third portion.
8. The electronic device of claim 1 , further comprising:
a tuning element configured to fine tune the first and second portions to remove a detuning effect.
9. An antenna system of a wireless device, comprising:
a main antenna coupled to the transceiver and configured to enable the transceiver to operate in at least four wireless frequency bands; and
a diversity antenna coupled to the transceiver, the diversity antenna configured to receive signals in at least the four wireless frequency bands and configured as an inverted F-antenna, the diversity antenna comprising:
a first portion having a first end and a second end, the first portion configured to enable the transceiver to receive a signal in a first low-band frequency of the four frequency bands;
a second portion connected to the first end of the first portion, the second portion configured to enable the transceiver to receive signals in first and second high-band frequencies of the four frequency bands;
a third portion RF coupled to the first portion when the third portion is connected to ground, the third portion configured to tune the first portion such that the transceiver receives a signal in a second low-band frequency of the four frequency bands; and
a switch connected between the third portion and the ground, wherein when the switch is open, the first portion enables the transceiver to receive the signal in the first low-band frequency, and wherein when the switch is closed, the third portion tunes the first portion to enable the transceiver to receive the signal in the second low-band frequency.
10. The antenna system of claim 9 , wherein the first high-band frequency is in a 2100 MHz frequency band, the second high-band frequency is in a 1900 MHz frequency band, the first low-band frequency is in a 850 MHz frequency band, and the second low-band frequency is in a 700 MHz frequency band.
11. The antenna system of claim 9 , wherein the third portion extends from a first end to a second end such that the first end of the third portion is substantially adjacent to the second end of the first portion.
12. The antenna system of claim 11 , wherein a disposition of the first end of the third portion relative to the second end of the first portion generates a highest radio frequency (RF) voltage.
13. The antenna system of claim 9 , further comprising:
a printed circuit board (PCB) comprising;
a feed connected to the first portion;
a first ground connected to the first portion; and
a second ground connected to the third portion through the switch.
14. The antenna system of claim 9 , wherein the first portion and the third portion are separated by a gap, wherein the first portion and the third portion are RF coupled when the third portion is connected to the ground.
15. The antenna system of claim 14 , wherein the third portion tunes the first low-band frequency of the first portion in a predetermined manner as a function of the gap and a length of the third portion.
16. A diversity antenna of a wireless device, the wireless device including a wireless transceiver and a main antenna, the diversity antenna, comprising:
a first portion having a first end and a second end, the first portion configured to enable the transceiver to receive a signal in a first low-band frequency of four frequency bands in which the transceiver is enabled to operate via the main antenna;
a second portion connected to the first end of the first portion, the second portion configured to enable the transceiver to receive signals in first and second high-band frequencies of the four frequency bands;
a third portion RF coupled to the first portion when the third portion is connected to ground, the third portion configured to tune the first portion such that the transceiver receives a signal in a second low-band frequency of the four frequency bands; and
a switch connected between the third portion and the ground, wherein when the switch is open, the first portion enables the transceiver to receive the signal in the first low-band frequency, and wherein when the switch is closed, the third portion tunes the first portion to enable the transceiver to receive the signal in the second low-band frequency.
17. The diversity antenna of claim 16 , wherein the first high-band frequency is in a 2100 MHz frequency band, the second high-band frequency is in a 1900 MHz frequency band, the first low-band frequency is in a 850 MHz frequency band, and the second low-band frequency is in a 700 MHz frequency band.
18. The diversity antenna of claim 16 , further comprising:
a printed circuit board (PCB) comprising:
a feed connected to the first portion;
a first ground connected to the first portion; and
a second ground connected to the third portion through the switch.
19. The diversity antenna of claim 16 , wherein the first portion and the third portion are separated by a gap, wherein the first portion and the third portion are RF coupled when the third portion is connected to the ground.
20. The diversity antenna of claim 19 , wherein the third portion tunes the first low-band frequency of the first portion in a predetermined manner as a function of the gap and a length of the third portion.