Energy harvesting circuit

• US 20050104553A1
• Filed: 10/18/2004
• Published: 05/19/2005
• Est. Priority Date: 10/29/2003
• Status: Active Grant

• Current Assignee: University of Pittsburgh of The Commonwealth System of Higher Education
• Original Assignee: University of Pittsburgh of The Commonwealth System of Higher Education
• Inventors: Mickle, Marlin H., Capelli, Christopher C., Swift, Harold
• Granted Patent: US 7,084,605 B2
• Time in Patent Office: Days
• US Class Current: 320/101
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01Q 1/248 provided with an AC/DC converting device, e.g. rectennas
• CPC Class Codes: H02J 50/001 Energy harvesting or scavenging
• CPC Class Codes: H02J 50/27 characterised by the type of receiving antennas, e.g. rectennas
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A station having a means for receipt of ambient energy from the environment and energizing power storage devices of objects of interest comprising one or more antennae and circuitry for converting said ambient energy into DC power for energizing said power storage devices. The circuitry for converting the ambient energy into DC power may include a rectifier/charge pump. The antenna of the station is tuned to maximize DC energy at the output of the rectifier/charge pump. The station can be used to energize power storage devices including capacitors and batteries that are used in electronic devices, such as cell phones, cameras, PDAs. Various antenna constructions may be employed.

Claims

1. A remote station for receiving ambient energy from the environment and energizing power storage devices of objects of interest comprising:

at least one antenna,

circuitry for converting said ambient energy into DC power for energizing said power storage devices,

said circuitry for converting said ambient energy into DC power including a rectifier/charge pump, and

said antenna being tuned to generally maximize DC energy at the output of the rectifier/charge pump.

2. The remote station of claim 1 wherein said at least one antenna can be connected to at least one tuning element, or tuning elements structured for energy harvesting.

3. The remote station of claim 1 wherein said at least one antenna is a plurality of antennae that can be connected wherein the DC outputs of each antenna is combined in series to obtain a higher voltage.

4. The remote station of claim 1 wherein said at least one antenna is a plurality of antennae wherein an RF combiner or balun is used to combine ambient energy harvested from said antennae prior to the circuitry for converting said transmitted energy into DC power.

5. The remote station of claim 1 wherein said at least one antenna includes separate antennae that are tuned to different frequencies so as to harvest energy from a broadband RF spectrum.

6. The remote station of claim 1 wherein the antenna includes separate broadband antennae that are each tuned to different frequency spectrums so as to harvest energy from a broadband RF spectrum.

7. The remote station of claim 6 wherein the antenna includes separate broadband antennae that are each tuned to the same portion of the frequency spectrums so as to harvest energy from a broadband RF spectrum.

8. The remote station of claim 1 wherein the ambient energy is RF power.

9. The remote station of claim 1 wherein each antenna is a wideband antenna system for substantially continuous coverage of about 20 KHz to 30 MHz radio frequency spectrum.

10. The remote station of claim 1 wherein each antenna is a wideband antenna system for continuous coverage of about 1.5 MHz to 30 MHz radio frequency spectrum.

11. The remote station of claim 1 wherein each antenna is a wideband antenna system for continuous coverage of about 30 MHz to 3 GHz radio frequency spectrum.

12. A remote station for receipt of ambient energy from the environment and energizing power storage devices of objects of interest comprising

at least two antennae,

an RF combiner, and

circuitry for converting said ambient energy into DC power for energizing said power storage devices:

said antennae are tuned to a fixed frequency spectrum, and

said RF combiner is used to combine ambient energy harvested from said antennae prior to the circuitry for converting said transmitted energy into DC power.

13. A remote station for receiving ambient energy from the environment and energizing power storage devices of objects of interest comprising

at least one antenna,

circuitry for converting said ambient energy into DC power for energizing said power storage devices,

at least two charging devices, and

a switch for switching between said devices.

14. The remote station of claim 13 wherein

at least two said charging devices having different charging dynamics.

15. The remote station of claim 14 wherein

said charging devices being capacitors.

16. A remote station for receiving ambient energy from the environment and energizing power storage devices of objects of interest comprising

at least one antenna,

circuitry for converting said ambient energy into DC power for energizing said power storage devices, and

a feedback device for providing feedback to the tuning mechanism to adjust the tuner for a higher level of energy harvesting.

17. A remote station for receipt of ambient energy from the environment and energizing power storage devices of objects of interest comprising:

a plurality of antennae,

circuitry for converting said ambient energy into DC power for energizing said power storage devices, and

said antennae generally occupying a fixed geographic area.

18. The remote station of claim 17 wherein

said antennae sharing said fixed geographic area.