Methods and apparatus utilizing multiple radars in object detection for wireless power transfer

1. An apparatus for detecting an object in a charging area of a wireless power transfer system having a base pad with first and second sides and configured to wirelessly charge a chargeable energy storage device, the apparatus comprising:

a plurality of radar transceivers, each of the plurality of radar transceivers comprising a transmit antenna and a receive antenna; and

a processor configured to:

instruct first and second radar transceivers of the plurality of radar transceivers to transmit first and second radar signals, respectively, during a first time slot of a plurality of time slots, wherein the first radar transceiver is integrated with the first side of the base pad and the second radar transceiver is integrated with the second side of the base pad, the first side being different from the second side,

instruct the first and second radar transceivers to receive first and second reflected radar signals, respectively, during the first time slot, and

detect a presence of the object in the charging area based on the first and second reflected radar signals.

2. The apparatus of claim 1 , wherein the processor is further configured to:

instruct third and fourth radar transceivers of the plurality of radar transceivers to transmit third and fourth radar signals, respectively, during a second time slot of the plurality of time slots, wherein the third radar transceiver is integrated with a third side of the base pad and the fourth radar transceiver is integrated with a fourth side of the base pad;

instruct the third and fourth radar transceivers to receive third and fourth reflected radar signals, respectively, during the second time slot; and

detect the presence of the object in the charging area based on the third and fourth reflected radar signals.

3. The apparatus of claim 2 , wherein the third side is the same as the first side and wherein the fourth side is the same as the second side.

4. The apparatus of claim 2 , wherein the third side is different from the first and second sides and wherein the fourth side is different form the first and second sides.

5. The apparatus of claim 1 , wherein the processor is further configured to reduce an amount of power provided by the wireless power transfer system in response to detecting the object in the charging area.

6. The apparatus of claim 1 , wherein a first transmitter of the first radar transceiver is separated from a first receiver of the second radar transceiver by a distance greater than a separation distance between a first transmitter of the second radar transceiver and the first receiver of the second radar transceiver.

7. The apparatus of claim 1 , wherein the processor is further configured to disable a transmitting capability of the first and second radar transceivers outside of the first time slot.

8. The apparatus of claim 1 , wherein the processor is further configured to disable a receiving capability of the first and second radar transceivers outside of the first time slot.

9. A method for detecting an object in a charging area of a wireless power transfer system having a base pad with first and second sides and configured to wirelessly charge a chargeable energy storage device, the method comprising:

instructing first and second radar transceivers of a plurality of radar transceivers each comprising a transmit antenna and a receive antenna to transmit first and second radar signals, respectively, during a first time slot of a plurality of time slots, wherein the first radar transceiver is integrated with the first side of the base pad and the second radar transceiver is integrated with the second side of the base pad, the first side being different from the second side;

instructing the first and second radar transceivers to receive first and second reflected radar signals, respectively, during the first time slot; and

detecting a presence of the object in the charging area based on the first and second reflected radar signals.

10. The method of claim 9 , further comprising:

instructing third and fourth radar transceivers of the plurality of radar transceivers to transmit third and fourth radar signals, respectively, during a second time slot of the plurality of time slots, wherein the third radar transceiver is integrated with a third side of the base pad and the fourth radar transceiver is integrated with a fourth side of the base pad;

instructing the third and fourth radar transceivers to receive third and fourth reflected radar signals, respectively, during the second time slot; and

detecting the presence of the object in the charging area based on the third and fourth reflected radar signals.

11. The method of claim 10 , wherein the third side is the same as the first side and wherein the fourth side is the same as the second side.

12. The method of claim 10 , wherein the third side is different from the first and second sides and wherein the fourth side is different form the first and second sides.

13. The method of claim 9 , further comprising reducing an amount of power provided by the wireless power transfer system in response to detecting the object in the charging area.

14. The method of claim 9 , wherein a first transmitter of the first radar transceiver is separated from a first receiver of the second radar transceiver by a distance greater than a separation distance between a first transmitter of the second radar transceiver and the first receiver of the second radar transceiver.

15. The method of claim 9 , further comprising disabling a transmitting capability of the first and second radar transceivers outside of the first time slot.

16. The method of claim 9 , further comprising disabling a receiving capability of the first and second radar transceivers outside of the first time slot.

17. An apparatus for detecting an object in a charging area of a wireless power transfer system having a base pad with first and second sides and configured to wirelessly charge a chargeable energy storage device, the apparatus comprising:

a plurality of means for transmitting and receiving radar signals, each of the plurality of means for transmitting and receiving radar signals comprising a means for transmitting and a means for receiving;

means for instructing first and second means for transmitting and receiving radar signals to transmit first and second radar signals, respectively, during a first time slot of a plurality of time slots, wherein the first means for transmitting and receiving radar signals is integrated with the first side of the base pad and the second means for transmitting and receiving radar signals is integrated with the second side of the base pad, the first side being different from the second side on the base pad,

means for instructing the first and second means for transmitting and receiving radar signals to receive first and second reflected radar signals, respectively, during the first time slot;

means for detecting a presence of the object in the charging area based on the first and second reflected radar signals.

18. The apparatus of claim 17 , wherein the plurality of means for transmitting and receiving radar signals is a plurality of radar transceivers, wherein the means for instructing first and second means for transmitting and receiving radar signals to transmit first and second radar signals, respectively, is a processor, wherein the means for instructing the first and second means for transmitting and receiving radar signals to receive first and second reflected radar signals, respectively is the processor, and wherein the mean for detecting a presence of the object is the processor.

19. The apparatus of claim 18 , further comprising:

means for instructing third and fourth means for transmitting and receiving radar signals to transmit third and fourth radar signals, respectively, during a second time slot of the plurality of time slots, wherein the third means for transmitting and receiving radar signals is integrated with a third side of the base pad and the fourth means for transmitting and receiving radar signals is integrated with a fourth side of the base pad;

means for instructing the third and fourth means for transmitting and receiving radar signals to receive third and fourth radar signals, respectively, during the second time slot; and

means for detecting the presence of the object in the charging area based on the third and fourth reflected radar signals.

20. The apparatus of claim 19 , wherein the third side is the same as the first side and wherein the fourth side is the same as the second side or wherein each of the third and fourth sides is different from the first and second sides.