Method of making and using an apparatus for a locomotive micro-implant using active electromagnetic propulsion
Described is a locomotive implant for usage within a predetermined magnetic field. In one embodiment magnetohydrodynamics is used to generate thrust with a plurality of electrodes. In another embodiment, asymmetric drag forces are used to generate thrust.
1. An apparatus for wireless power transmission to an implantable device operating in a biological environment, the apparatus comprising:
a wireless power transmitter operating at a power signal frequency and having one or more transmitting antennae configured to transmit a power signal and a first match circuit with a tuned impedance; and
a wireless power receiver having one or more receiving antennae configured to receive the transmitted power signal as a received power signal and a second match circuit with a tuned impedance;
wherein the power signal frequency has a wavelength in the biological environment and the wireless power transmitter and the wireless power receiver are set apart by a distance in the range between wavelength/100 and wavelength*100 in a medium of the biological environment.
2. The apparatus according to claim 1 , wherein the first match circuit at the wireless power transmitter and the second match circuit at the wireless power receiver are tuned to maximize power transfer efficiency between them using simultaneous conjugate matching.
3. The apparatus according to claim 1 , wherein the one or more transmitting antennae comprise a single turn loop or a coil with multiple turns.
4. The apparatus according to claim 1 , wherein the one or more receiving antennae comprise a single turn loop or a coil with multiple turns.
5. The apparatus according to claim 1 , wherein the implantable device is powered by the received power signal and does not include a battery.
6. The apparatus according to claim 1 , wherein the implantable device incorporates a charging device to accumulate power over time.
7. The apparatus according to claim 1 , wherein the implantable device includes a capacitor for storing energy from the received power signal.
8. The apparatus according to claim 1 , wherein the one or more receiving antennae are smaller in area than the one or more transmitting antennae.
9. The apparatus according to claim 8 , wherein the one or more receiving antennae are up to 100 times smaller in area than the one or more transmitting antennae.
10. The apparatus according to claim 8 , where an optimal transmission frequency is chosen by maximizing link gain and link efficiency between the wireless power transmitter and the wireless power receiver taking into account the asymmetry in area between the one or more transmitting antennae and the one or more receiving antennae at a target depth of the implantable device in the biological environment.
11. The apparatus according to claim 1 , wherein the transmitted power signal is modulated with data, which is received by the one or more receiving antennae.
12. The apparatus according to claim 1 , wherein data is transferred from the implantable device to the wireless power transmitter by varying impedance of the one or more receiving antennae.
13. The apparatus according to claim 1 , wherein the wireless power transmitter detects properties of the implantable device based on implicit feedback that indicates a change in impedance of the one or more transmitting antennae.
14. An apparatus for determining a wireless transmission link gain in an implantable device operating in a biological environment, the apparatus comprising:
a wireless power transmitter operating at a power signal frequency and having one or more transmitting antennae configured to transmit a power signal and a circuit for detecting feedback from the one or more transmitting antenna; and
a wireless power receiver having one or more receiving antennas configured to receive the transmitted power signal as a received power signal;
wherein the wireless power transmitter and the wireless power receiver are disposed apart with a distance between them ranging between wavelength/100 and wavelength*100 of the power signal frequency in a medium of the biological environment, and, wherein the feedback from the one or more transmitting antennae is used to calculate a link gain between the wireless power transmitter and the wireless power receiver.
15. The apparatus according to claim 14 , wherein the one or more transmitting antennae comprises a single turn loop or a coil with multiple turns.
16. The apparatus according to claim 14 , wherein the one or more receiving antennae comprise a single turn loop or a coil with multiple turns.
17. The apparatus according to claim 14 , wherein the feedback is implicit.
18. The apparatus according to claim 17 , wherein the implicit feedback is sensed as a change in impedance of the one or more transmitting antennae.
19. The apparatus according to claim 14 , wherein the feedback is explicit.
20. The apparatus according to claim 19 , wherein the explicit feedback is data sent from the wireless power receiver.
21. The apparatus according to claim 20 , wherein the data includes information about the received power.
22. The apparatus according to claim 14 , wherein the feedback is a combination of implicit and explicit information.
23. The apparatus according to claim 14 , wherein the feedback is used to make adjustments to the transmitted power signal.
24. The apparatus according to claim 14 , wherein the feedback is used to determine a relative position of the one or more transmitting antennae and the one or more receiving antennae.
25. The apparatus according to claim 14 wherein the wireless transmission link gain is adjusted by applying one or more of: impedance matching between the wireless power transmitter and the wireless power receiver, beam forming by locating the wireless power receiver, and, tuning the power signal frequency.