Methods and apparatus utilizing digital signal processing of ultra wide band radar signals for living object detection in wireless power transfer applications

1. An apparatus for detecting an object in a detection area of a wireless power transfer system, the apparatus comprising:

a receiver configured to receive a plurality of radar signals from a radar transceiver;

a processor configured to:

convert the plurality of radar signals to a plurality of digital radar signals,

generate a first plurality of filtered radar signals based on removing first frequency content outside a first frequency band from the plurality of digital radar signals,

generate a second plurality of filtered radar signals based on removing second frequency content below a first threshold frequency from the first plurality of filtered radar signals, wherein removing the second frequency content includes passing through those signals caused by living or moving objects,

down-convert the second plurality of filtered radar signals into a plurality of complex digital baseband signals, and

detect a presence of the object in the detection area based at least in part on the plurality of complex digital baseband signals.

2. The apparatus of claim 1 , wherein each of the plurality of complex digital baseband signals comprises an in-phase component and a quadrature-phase component.

3. The apparatus of claim 1 , wherein the processor is configured to remove the frequency content below the first threshold frequency before down-converting the second plurality of filtered radar signals.

4. The apparatus of claim 1 , wherein the processor is further configured to remove frequency content above a second frequency threshold from the plurality of complex digital baseband signals.

5. The apparatus of claim 1 , wherein the processor is further configured to remove a DC component from the plurality of digital radar signals.

6. The apparatus of claim 1 , wherein the removal of digital radar signals from the plurality of digital radar signals occurs before the down-conversion of the plurality of digital radar signals and wherein the processor is further configured to amplify the plurality of digital radar signals, reduce an amount of noise in the plurality of digital radar signals and remove frequency components of the plurality of digital radar signals above a second threshold frequency.

7. The apparatus of claim 1 , wherein the processor configured to detect the presence of the object in the detection area comprises the processor configured to detect a range, a speed, and a direction of the object in the detection area based at least in part on the plurality of complex digital baseband signals at least partly by sensing a Doppler shift present in the plurality of complex digital baseband signals.

8. A method for detecting an object in a detection area of a wireless power transfer system, the method comprising:

receiving a plurality of radar signals from a radar transceiver;

converting the plurality of radar signals to a plurality of digital radar signals;

generating a first plurality of filtered radar signals based on removing first frequency content outside a first frequency band from the plurality of digital radar signals;

generating a second plurality of filtered radar signals based on removing second frequency content below a first threshold frequency from the first plurality of filtered radar signals, wherein removing the second frequency content includes passing through those signals caused by living or moving objects;

down-converting the second plurality of filtered radar signals into a plurality of complex digital baseband signals; and

detecting a presence of the object in the detection area based at least in part on the plurality of complex digital baseband signals.

9. The method of claim 8 , wherein each of the plurality of complex digital baseband signals comprises an in-phase component and a quadrature-phase component.

10. The method of claim 8 , further comprising removing the frequency content below the first threshold frequency before down-converting the second plurality of filtered radar signals.

11. The method of claim 8 , further comprising removing frequency content above a second frequency threshold from the plurality of complex digital baseband signals.

12. The method of claim 8 , further comprising removing a DC component from the plurality of digital radar signals.

13. The method of claim 8 , wherein the removal of digital radar signals from the plurality of digital radar signals occurs before the down-conversion of the plurality of digital radar signals and further comprising amplifying the plurality of digital radar signals, reducing an amount of noise in the plurality of digital radar signals, and removing frequency components of the plurality of digital radar signals above a second threshold frequency.

14. The method of claim 8 , wherein the detecting the presence of the object in the detection area comprises detecting a range, a speed, and a direction of the object in the detection area based at least in part on the plurality of complex digital baseband signals comprises sensing a Doppler shift present in the plurality of complex digital baseband signals.

15. A non-transitory, computer-readable medium comprising code that, when executed, causes an apparatus for detecting an object in a detection area of a wireless power transfer system to:

receive a plurality of radar signals from a radar transceiver;

convert the plurality of radar signals to a plurality of digital radar signals;

generate a first plurality of filtered radar signals based on removing first frequency content outside a first frequency band from the plurality of digital radar signals;

generate a second plurality of filtered radar signals based on removing second frequency content below a first threshold frequency from the first plurality of filtered radar signals, wherein removing the second frequency content includes passing through those signals caused by living or moving objects;

down-convert the second plurality of filtered radar signals into a plurality of complex digital baseband signals; and

detect a presence of the object in the detection area based at least in part on the plurality of complex digital baseband signals.

16. The medium of claim 15 , wherein each of the plurality of complex digital baseband signals comprises an in-phase component and a quadrature-phase component.

17. The medium of claim 15 , wherein the code, when executed, causes the apparatus to remove the frequency content below the first threshold frequency before down-converting the second plurality of filtered radar signals.

18. The medium of claim 15 , wherein the code, when executed, causes the apparatus to remove frequency content above a second frequency threshold from the plurality of complex digital baseband signals.

19. The medium of claim 15 , wherein the code, when executed, causes the apparatus to remove a DC component from the plurality of digital radar signals.

20. The medium of claim 15 , wherein the removal of digital radar signals from the plurality of digital radar signals occurs before the down-conversion of the plurality of digital radar signals and wherein the code, when executed, is further configured to cause the apparatus to amplify the plurality of digital radar signals, reduce an amount of noise in the plurality of digital radar signals, and remove frequency components of the plurality of digital radar signals above a second threshold frequency.

21. The medium of claim 15 , wherein the code that, when executed, causes the apparatus to detect the presence of the object in the detection area further causes the apparatus to detect a range, a speed, and a direction of the object in the detection area based at least in part on the plurality of complex digital baseband signals at least partly by sensing a Doppler shift present in the plurality of complex digital baseband signals.

22. An apparatus for detecting an object in a detection area of a wireless power transfer system, the apparatus comprising:

means for receiving a plurality of radar signals from a radar transceiver;

means for converting the plurality of radar signals to a plurality of digital radar signals;

generate a first plurality of filtered radar signals based on removing first frequency content outside a first frequency band from the plurality of digital radar signals;

means for generating a second plurality of filtered radar signals based on removing second frequency content below a first threshold frequency from the first plurality of filtered radar signals, wherein remaining frequency content includes those signals caused by living or moving objects and wherein the first threshold frequency distinguishes between living or moving objects and other objects;

means for down-converting the plurality of filtered radar signals into a plurality of complex digital baseband signals; and

means for detecting a presence of the object in the detection area based at least in part on the plurality of complex digital baseband signals.

23. The apparatus of claim 22 , wherein each of the plurality of complex digital baseband signals comprises an in-phase component and a quadrature-phase component.

24. The apparatus of claim 22 , wherein the means for removing the frequency content below the first threshold frequency operates before the means for down-converting the plurality of digital radar signals.

25. The apparatus of claim 22 , further comprising means for removing frequency content above a second frequency threshold from the plurality of complex digital baseband signals.

26. The apparatus of claim 22 , further comprising means for removing a DC component from the plurality of digital radar signals.

27. The apparatus of claim 22 , wherein the removal of digital radar signals from the plurality of digital radar signals occurs before the down-conversion of the plurality of digital radar signals and wherein the apparatus further comprises means for amplifying the plurality of digital radar signals, means for reducing an amount of noise in the plurality of digital radar signals, and means for removing frequency components of the plurality of digital radar signals above a second threshold frequency.

28. The apparatus of claim 22 , wherein the means for detecting the presence of the object in the detection area comprises means for detecting a range, a speed, and a direction of the object based at least in part on the plurality of complex digital baseband signals senses a Doppler shift present in the plurality of complex digital baseband signals.