Wireless charger receiver-side communication interference elimination

1. A wireless power receiver unit comprising:

a power pick-up unit configured to receive a wireless power signal;

a communication modulator to apply a modulation to the received wireless power signal; and

a filter configured to suppress a load signal in the 1 to 2 kHz frequency band from a load of the wireless power receiver unit to prevent interference with the modulation.

2. The wireless power receiver unit of claim 1 , wherein the filter is an active filter configured to constantly suppress the interference from the load.

3. The wireless power receiver unit of claim 2 , wherein the active filter comprises a current regulator.

4. The wireless power receiver unit of claim 3 , wherein the current regulator comprises an intermediate buffer.

5. The wireless power receiver unit of claim 4 , wherein the intermediate buffer comprises:

an input stage;

a buffer capacitor; and

an output stage comprising a DC/DC converter.

6. The wireless power receiver unit of claim 5 , wherein the input stage comprises a controlled current source or a controlled voltage source.

7. The wireless power receiver unit of claim 1 , wherein the filter is a passive filter configured to suppress the interference during a communication stage.

8. The wireless power receiver unit of claim 7 , wherein the passive filter comprises one of a list of components, the list comprising:

a capacitor;

a resistor; and

an inductor.

9. The wireless power receiver unit of claim 7 , wherein the passive filter comprises a bypass switch to bypass the passive filter outside of the communication stage.

10. The wireless power receiver unit of claim 1 , wherein the filter is coupled to a controller to manage the operation of the filter.

11. The wireless power receiver unit of claim 1 , further comprising at least one modulation component configured to generate a communication by signal modulation.

12. A method for suppressing wireless power signal interference, the method comprising:

receiving a wireless power signal during a power mode;

modulating the received wireless power signal during a communication stage, wherein the communication stage occurs during the power mode; and

filtering a load signal in the 1 to 2 kHz frequency band to prevent interference affecting the modulation.

13. The method of claim 12 , further comprising initiating a passive filter in response to detection of initiation of the communication stage.

14. The method of claim 13 , further comprising bypassing the passive filter in response to detection of completion of the communication stage.

15. The method of claim 12 , wherein filtering the load signal comprises actively filtering the load signal.

16. The method of claim 15 , further comprising actively filtering the load signal in response to an input from a controller.

17. A wireless power system comprising:

a power sending unit configured to transmit a wireless power signal; and

a power receiver unit configured to receive the wireless power signal and modulate the received power signal to communicate with the power sending unit, wherein the power receiver unit comprises:

a filter configured to suppress a load signal in the 1 to 2 kHz frequency band to prevent interference in the modulated wireless power signal;

a communication modulator to apply a modulation to the received wireless power signal; and

a receiver communications and control unit configured to send input to the communication modulator to manage the signal modulation process.

18. The system of claim 17 , wherein the filter is an active filter configured to constantly suppress the load signal to prevent interference affecting the modulated wireless power signal.

19. The system of claim 17 , wherein the filter is a passive filter configured to suppress the load signal during a communication stage, wherein the communication stage is a period of time in which the power signal receiver modulates the wireless power signal.