Energy Harvesting System

• US 20160020631A1
• Filed: 02/05/2013
• Published: 01/21/2016
• Est. Priority Date: 02/09/2012
• Status: Active Grant

• Current Assignee: Humavox Ltd.
• Original Assignee: Humavox Ltd.
• Inventors: Manova-Elssibony, Asaf
• Granted Patent: US 9,728,998 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61N 1/3785 generated by biological activity or substance, e.g. body movement
• CPC Class Codes: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 5/00 Circuit arrangements for transfer of electric power between ac networks and dc networks H02J3/36 takes precedence
• CPC Class Codes: H02J 50/001 Energy harvesting or scavenging
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/27 characterised by the type of receiving antennas, e.g. rectennas
• CPC Class Codes: H03H 7/0138 Electrical filters or coupling circuits
• CPC Class Codes: H03H 7/38 Impedance-matching networks

Abstract

A system is presented for harvesting electromagnetic energy propagating in surroundings. The system comprises an antenna unit, a harvesting unit, and an input signal adapting circuit. The antenna unit is configured for receiving external electromagnetic radiation from the surroundings and producing a corresponding electric output. The harvesting unit comprises at least one energy harvesting circuit each configured and operable for receiving signals indicative of the output of the antenna unit and generating and storing corresponding electric charge, the harvesting circuit comprising: a rectifying unit comprising a plurality of rectifiers each configured and operable to receive AC electric signals and generate corresponding DC electric power; and a charge collection unit configured and operable to receive the plurality of DC electric powers from said rectifying unit and converting and accumulating them into the electric charge presenting harvested energy. The input signal adapting circuit has an input connected to the antenna unit and an output connected to the rectifying unit, the input signal adapting circuit being configured and operable for adjusting a predetermined electrical property of the antenna unit and rectifying unit to thereby optimize receipt of the electric output of the antenna unit to the harvesting circuit.

Claims

1. A system for harvesting electromagnetic energy propagating in surroundings, said system comprising:

an antenna unit configured for receiving external electromagnetic radiation from the surroundings and producing a corresponding electric output;

a harvesting unit comprising at least one energy harvesting circuit each configured and operable for receiving signals indicative of the output of the antenna unit and generating and storing corresponding electric charge, the harvesting circuit comprising;

a rectifying unit comprising a plurality of rectifiers each configured and operable to receive AC electric signals and generate corresponding DC electric power; and

a charge collection unit configured and operable to receive the plurality of DC electric powers from said rectifying unit and converting and accumulating them into the electric charge presenting harvested energy; and

an input signal adapting circuit having an input connected to the antenna unit and an output connected to the rectifying unit, the input signal adapting circuit being configured and operable for adjusting a predetermined electrical property of the antenna unit and rectifying unit to thereby optimize receipt of the electric output of the antenna unit to the harvesting circuit.

2. A system according to claim 1, wherein said antenna unit comprises at least two conductive elements positioned in at least two different transmission media being different in at least one of electric and magnetic properties.

3. A system according to claim 1, wherein said at least two different transmission media include at least two different animate tissues.

4. A system according to claim 1, wherein said at least two different transmission media include animate tissue and air.

5. A system according to claim 1, wherein said input signal adapting unit is configured to adjust impedance of the antenna unit to impedance of the rectifying unit.

6. A system according to claim 5, wherein said input signal adapting unit comprises an impedance matching unit and a filtering unit connected to the impedance matching unit, the impedance matching unit being configured to match between the impedances of the antenna unit and the filtering unit, and the filtering unit being configured and operable for sorting the received RF band propagating in the surrounding into a predefined number of subbands with a predetermined central frequency, band width and strength for each subband, the predefined number of subbands corresponding to a number of the rectifiers in the rectifying unit.

7. A system according to claim 5, wherein said input signal adjusting unit comprises:

an adaptive impedance matching unit configured and operable to controllably adjust impedance of the rectifiers of the rectifying unit to signal intensities of multiple frequency bands received by the antenna unit; and

a control unit connectable to the adaptive impedance matching unit and configured and operable operation thereof.

8. A system according to claim 1, wherein said charge collection unit comprises a signal summing unit comprising a switching topology circuit and a controller, the switching topology circuit comprising a predetermined number of capacitors having relatively small capacitance values and being connected to output of the corresponding number of the rectifiers respectively, and a storage capacitor of a relatively large capacitance value, the switching topology circuit being adapted to controllably switch between the plurality of DC signals received from the plurality of rectifiers respectively with the corresponding plurality of said capacitors of the relatively small capacitance values for power summation and storage of corresponding charge on said capacitor of the relatively large capacitance value.

9. A system according to claim 1, wherein said charge collection unit comprises a signal summing unit comprising a voltage to current unit comprising a predetermined number of voltage to current conversion circuits having inputs connected to outputs of the corresponding number of the rectifiers respectively, and outputs connected to a storage a capacitor, the voltage to current unit being thereby adapted to convert and sum the plurality of DC signals received from the plurality of rectifiers via the plurality of voltage to current conversion circuits.

10. A system according to claim 1, comprising a control unit connected to at least one of the input signal adapting unit and the charge collection unit and configured and operable to control operation of the harvesting circuit.

11. A system according to claim 10, wherein said control unit is connected to at least said charge collection unit which comprises a switching topology circuit comprising a predetermined number of capacitors having relatively small capacitance values and being connected to output of the corresponding number of the rectifiers respectively, and a storage capacitor of a relatively large capacitance value, the switching topology circuit being adapted to controllably switch between the plurality of DC signals received from the plurality of rectifiers respectively with the corresponding plurality of said capacitors of the relatively small capacitance values for power summation and storage of corresponding charge on said capacitor of the relatively large capacitance value.

12. A system according to claim 1, wherein said harvesting circuit comprises a connection port for connecting output of the charge collection unit to at least one electrical load.

13-16. -16. (canceled)

17. An antenna unit configured and operable for receiving external electromagnetic radiation from surroundings and producing a corresponding output electric signal, said antenna unit comprising at least two conductive elements positioned in at least two different transmission media being different in at least one of electric and magnetic properties, such that received external electromagnetic radiation creates a potential difference between the at least two conductive elements producing an output electric signal, thereby allowing uptake of the external electromagnetic radiation from the surroundings.

18. An antenna unit according to claim 17, wherein said at least two different transmission media include different animate tissues.

19. An antenna unit according to claim 17, being attached to an animate body, wherein said at least two different transmission media include animate tissue and air.

20. (canceled)

21. An input signal adapting unit for use with an antenna exposed to electromagnetic radiation of Radio Frequency (RF) band propagating in surroundings, the input signal adapting unit comprising an impedance matching unit and a filtering unit connected to the impedance matching unit, the impedance matching unit being configured to match between impedances of the antenna unit and the filtering unit, and the filtering unit being adapted for sorting the RF band into a predefined number of subbands of a predetermined frequency, bandwidth and strength for each subband.

22. (canceled)

23. A charge collection unit for use in an energy harvesting circuit, the charge collection unit comprising a signal summing unit adapted to receive a plurality of DC electric powers and sum them in the form of an electric charge on a storage capacitor, the signal summing unit comprising at least one of a switching topology unit and a voltage to current unit.

24. A charge collection unit according to claim 23, wherein the summing unit comprises the switching topology unit and a controller, the switching topology unit comprising a predetermined number of capacitors having relatively small capacitance values and being connectable to output of a corresponding number of rectifiers respectively, and connected to said storage capacitor of a relatively large capacitance value, the switching topology unit being adapted to controllably switch between DC sources received from the rectifiers with said predetermined number of the capacitors for power summation.

25. A charge collection unit according to claim 23, wherein said voltage to current unit comprises a predetermined number of voltage to current conversion circuits having inputs connectable to outputs of a corresponding number of rectifiers respectively, and outputs connected to the storage capacitor, the voltage to current unit being thereby configured and operable to convert and sum a plurality of DC sources received from the plurality of rectifiers via the voltage to current conversion circuits.

26. An energy harvesting unit comprising at least one energy harvesting circuit, wherein each energy harvesting circuit is configured and operable for receiving signals from an antenna unit and generating and storing corresponding electric charge, the harvesting circuit comprising:

an input signal adapting circuit connectable to output of an antenna unit;

a rectifying unit connected to output of the input signal adapting circuit, the rectifying unit comprising a plurality of rectifiers each configured and operable to receive AC electric signals and generate corresponding DC electric power; and

a charge collection unit configured and operable to receive the plurality of DC electric powers from said rectifying unit and converting and accumulating them into the electric charge presenting harvested energy;

the harvesting circuit having at least one of the following configurations;

(a) the input signal adapting unit comprises an impedance matching unit and a filtering unit connected to the impedance matching unit, the impedance matching unit being configured to match between impedances of the antenna unit and the filtering unit, and the filtering unit being adapted for sorting the RF band into a predefined number of subbands of a predetermined frequency, bandwidth and strength for each subband; and

(b) the charge collection unit comprises a signal summing unit adapted to receive a plurality of DC electric powers and sum them in the form of an electric charge on a storage capacitor, the signal summing unit comprising at least one of a switching topology unit and a voltage to current unit.