Multi-coil wireless charger validation

1. A test apparatus, comprising:

a receiving head configured to provide a measurement signal representative of electromagnetic flux received from one or more transmitting coils in a wireless charging surface of a charging device, wherein the receiving head includes an array of receiving coils, and wherein each receiving coil provides a local signal representative of electromagnetic flux detected by the each receiving coil;

a numerically-controlled stage configured to position the receiving head at a selected point in three-dimensional space above the wireless charging surface; and

a processor configured to:

cause the numerically-controlled stage to position the receiving head at the selected point in three-dimensional space;

use a plurality of local signals generated by the array of receiving coils to determine magnitude of electromagnetic flux or power received from the wireless charging surface proximate to the array of receiving coils; and

use the measurement signal to determine magnitude of the electromagnetic flux or power received from the wireless charging surface proximate to the selected point in three-dimensional space.

2. The test apparatus of claim 1 , wherein each receiving coil provides a current representative of electromagnetic flux detected by the each receiving coil, the test apparatus further comprising:

a receiving circuit configured to combine a plurality of currents provided by the array of receiving coils to obtain the measurement signal.

3. The test apparatus of claim 1 , further comprising:

a computer numerical control controller configured to operate the numerically-controlled stage responsive to one or more instructions received from the processor.

4. A test apparatus, comprising:

a receiving head configured to provide a measurement signal representative of total electromagnetic flux received from one or more transmitting coils in a wireless charging surface of a charging device, wherein the receiving head includes a loop receiver configured to be placed over an area that includes a plurality of transmitting coils of the wireless charging surface;

a numerically-controlled stage configured to position the receiving head at a selected point in three-dimensional space above the wireless charging surface; and

a processor configured to:

cause the numerically controlled stage to position the receiving head at the selected point in three-dimensional space; and

use the measurement signal to determine magnitude of the electromagnetic flux or power received from the wireless charging surface proximate to the selected point in three-dimensional space.

5. The test apparatus of claim 4 , wherein electromagnetic flux received from two of the plurality of transmitting coils have different phases.

6. A method for testing a charging surface, comprising:

positioning a receiving head at a selected point in three-dimensional space above a wireless charging surface in a charging device, wherein the receiving head is mounted on a numerically-controlled stage and includes an array of receiving coils, and wherein each receiving coil provides a local signal representative of electromagnetic flux detected by the each receiving coil;

determining a magnitude of electromagnetic flux or power received by each of the array of receiving coils;

receiving a measurement signal representative of electromagnetic flux received from one or more transmitting coils of a wireless charging surface proximate to the selected point in three-dimensional space; and

using the measurement signal to determine magnitude of the electromagnetic flux or power received from the wireless charging surface proximate to the selected point in three-dimensional space.

7. The method of claim 6 , further comprising:

combining currents generated by the array of receiving coils in response to the electromagnetic flux to obtain the measurement signal.

8. The method of claim 6 , further comprising:

modulating the electromagnetic flux received from the one or more transmitting coils in accordance with a digital signal carrying a command directed to charging device, wherein the electromagnetic flux is modulated by modifying an impedance of a circuit in the receiving head.

9. A method for testing a charging surface comprising:

positioning a receiving head at a selected point in three-dimensional space above a wireless charging surface in a charging device, wherein the receiving head is mounted on a numerically-controlled stage;

receiving a measurement signal representative of electromagnetic flux received from one or more transmitting coils of a wireless charging surface proximate to the selected point in three-dimensional space, wherein the receiving head comprises a loop receiver configured to be placed over an area that includes a plurality of transmitting coils of the wireless charging surface; and

using the measurement signal to determine magnitude of the electromagnetic flux or power received from the wireless charging surface proximate to the selected point in three-dimensional space.

10. The method of claim 9 , further comprising:

measuring current generated by the loop receiver in response to the electromagnetic flux; and

determining the magnitude of the electromagnetic flux or power received from the wireless charging surface based on the current generated by the loop receiver.

11. The method of claim 9 , wherein electromagnetic flux received from two of the plurality of transmitting coils have different phases.

12. A non-transitory processor readable storage medium, comprising code for:

positioning a receiving head at a selected point in three-dimensional space above a wireless charging surface of a charging device, wherein the receiving head is mounted on a numerically-controlled stage and includes an array of receiving coils, and wherein each receiving coil provides a local signal representative of electromagnetic flux detected by the each receiving coil;

determining a magnitude of electromagnetic flux or power received by each of the array of receiving coils;

receiving a measurement signal representative of electromagnetic flux received from one or more transmitting coils of a wireless charging surface proximate to the selected point in three-dimensional space; and

using the measurement signal to determine magnitude of the electromagnetic flux or power received from the wireless charging surface proximate to the selected point in three-dimensional space.

13. The storage medium of claim 12 , further comprising code for:

combining currents generated by the array of receiving coils in response to the electromagnetic flux to obtain the measurement signal.

14. The storage medium of claim 12 , further comprising code for:

modulating the electromagnetic flux received from the one or more transmitting coils in accordance with a digital signal carrying a command directed to charging device, wherein the electromagnetic flux is modulated by modifying an impedance of a circuit in the receiving head.

15. A non-transitory processor readable storage medium, comprising code for:

positioning a receiving head at a selected point in three-dimensional space above a wireless charging surface of a charging device, wherein the receiving head is mounted on a numerically-controlled stage;

receiving a measurement signal representative of electromagnetic flux received from one or more transmitting coils of a wireless charging surface proximate to the selected point in three-dimensional space, wherein the receiving head comprises a loop receiver configured to be placed over an area that includes a plurality of transmitting coils of the wireless charging surface, and

using the measurement signal to determine magnitude of the electromagnetic flux or power received from the wireless charging surface proximate to the selected point in three-dimensional space.

16. The storage medium of claim 15 , further comprising code for:

measuring current generated by the loop receiver in response to the electromagnetic flux; and

determining the magnitude of the electromagnetic flux or power received from the wireless charging surface based on the current generated by the loop receiver.

17. The storage medium of claim 15 , wherein electromagnetic flux received from two of the plurality of transmitting coils have different phases.