Near-field wireless device

1. A near-field wireless device, comprising:

a coil, including a first feed-point and a second feed-point, and configured to carry non-propagating quasi-static near-field magnetic-induction wireless signals;

a conductive surface, including a third feed-point, and configured to carry non-propagating quasi-static near-field electric-induction wireless signals;

a tuning circuit including a first tuning element, a second tuning element, and a mid-point;

wherein a first end of the first tuning element is coupled to the first feed-point;

wherein a first end of the second tuning element is coupled to the second feed-point;

wherein a second end of the first tuning element and a second end of the second tuning element are coupled to the mid-point; and

wherein the third feed-point is coupled to the mid-point.

2. The device of claim 1 :

wherein the mid-point is directly connected to a voltage reference wholly within the device.

3. The device of claim 1 :

wherein the mid-point is directly connected to a ground plane wholly within the device.

4. The device of claim 1 :

wherein the conductive surface is coupled to a ground plane with an electrical wire.

5. The device of claim 1 :

wherein the conductive surface is coupled to the mid-point with an electrical wire.

6. The device of claim 1 :

further comprising a reference plane;

wherein the mid-point is coupled to the reference plane; and

wherein the reference plane is configured to increase an effective electrical size of the conductive surface responsive to the near-field electric-induction wireless signals.

7. The device of claim 1 :

wherein either the first or second first tuning element is a capacitance tuning element.

8. The device of claim 1 :

wherein either the first or second first tuning element is a resistive tuning element.

9. The device of claim 1 :

wherein the conductive surface is configured to be placed within a first distance from the coil and a second distance from a user's body.

10. The device of claim 9 :

wherein the second distance is greater than the first distance.

11. The device of claim 1 :

wherein the conductive surface is a first conductive surface;

wherein the coil is configured as a second conductive surface; and

wherein the first and second conductive surfaces are configured to carry the near-field electric-induction wireless signals.

12. The device of claim 1 :

wherein the conductive surface is a first conductive surface;

further comprising a second conductive surface coupled to either the first feed-point or the second feed-point; and

wherein the first and second conductive surfaces are configured to carry the near-field electric-induction wireless signals.

13. The device of claim 1 :

wherein the coil includes a planar coil having a spiral wound wire.

14. The device of claim 1 :

wherein the coil includes a core having a helically wound wire around the core.

15. The device of claim 1 :

wherein the conductive surface is configured for on-body near-field communications.

16. The device of claim 1 :

wherein the first and second tuning elements are resistive elements, configured to vary a bandwidth of the wireless device.

17. The device of claim 1 :

wherein the first and second tuning elements are capacitive elements, configured to vary a resonant frequency of the wireless device.

18. The device of claim 1 :

wherein the electric-induction near-field signals are hosted by a user's body; and

wherein the user's body is at least one of: a human body, a vehicle body, a robot, a docking device, a physical coupling system, or a tool or storage station on an assembly line.

19. The device of claim 1 :

wherein the wireless device is embedded in at least one of: a wearable, a glucose monitor, a medical device, a smart watch, an earbud, a hearing aid, a headphone, an activity tracker, or a heart rate monitor.

20. The device of claim 1 :

wherein the third feed-point is fixedly attached to the mid-point.