Transponder-based microwave telemetry apparatus

• US 6,999,000 B2
• Filed: 07/29/2002
• Issued: 02/14/2006
• Est. Priority Date: 07/29/2002
• Status: Active Grant

• Current Assignee: Michigan Technological University
• Original Assignee: Michigan Technological University
• Inventors: Anderson, Carl, Campbell, Richard Lynn, Barna, Glen, Brumm, Douglas Bruce
• Primary Examiner(s): Horabik, Michael
• Assistant Examiner(s): JENKINS, KIMBERLY YVETTE
• Application Number:
  US10/207,489
• Publication Number:
  US 20040017299A1
• Time in Patent Office: 1,296 Days
• Field of Search: 34087001-87017, 340/455, 340/426.16
• US Class Current: 340/870.01
• CPC Class Codes: G01K 11/006 using measurement of the effect of a material on microwaves or longer electromagnetic waves, e.g. measuring temperature via microwaves emitted by the object G01K17/003, G01J5/00 take precedence; measuring the effect of a material on X-, gamma- or particle radiation G01K11/30
• CPC Class Codes: G08C 17/02 using a radio link

Abstract

A transponder-based microwave telemetry apparatus for moving machinery includes a microwave transmitter disposed outside the moving machinery to fill a chamber of the moving machinery with microwave energy. The transponder-based microwave telemetry apparatus also includes a transponder disposed inside the moving machinery for measuring a sensed condition of a part of the moving machinery and providing a modulated microwave signal that contains information on the sensed condition. The transponder-based microwave telemetry apparatus further includes a receiver disposed outside the moving machinery to separate modulated and continuous-wave signal components of the signal and extracts information from the modulated component.

Claims

1. A transponder-based microwave telemetry apparatus for moving machinery comprising:

a microwave transmitter disposed outside the moving machinery to fill a chamber of the moving machinery with microwave energy;

a transponder disposed inside the moving machinery for measuring a sensed condition of a part of the moving machinery, said transponder including an antenna and a switch electrically connected to said antenna, said switch turning said antenna ON and OFF to amplitude modulate incoming microwave energy, thereby providing a modulated microwave signal that contains information on the sensed condition; and

a receiver disposed outside the moving machinery to separate modulated and continuous-wave signal components of the signal and extract information from the modulated component.

2. A transponder-based microwave telemetry apparatus as set forth in claim 1 wherein said switch comprises a diode.

3. A transponder-based microwave telemetry apparatus as set forth in claim 1 wherein said transponder includes an information gathering circuit electrically connected to said switch.

4. A transponder-based microwave telemetry apparatus as set forth in claim 3 wherein said information gathering circuit comprises either one of a timer and oscillator chip.

5. A transponder-based microwave telemetry apparatus as set forth in claim 1 wherein said antenna of said transponder transmits the modulated signal and receives the microwave energy.

6. A transponder-based microwave telemetry apparatus as set forth in claim 3 wherein said transponder includes a power source electrically connected to said information gathering circuit.

7. A transponder-based microwave telemetry apparatus as set forth in claim 1 including a transmitting antenna electrically connected to said transmitter and extending into the moving machinery.

8. A transponder-based microwave telemetry apparatus as set forth in claim 1 including a receiving antenna electrically connected to said receiver and extending into the moving machinery.

9. A transponder-based microwave telemetry apparatus as set forth in claim 1 wherein said transmitter and said receiver are a single unit.

10. A transponder-based microwave telemetry apparatus for an internal combustion engine comprising:

a transponder disposed inside the engine for measuring a sensed condition of a piston in the engine, said transponder including an antenna and a switch electrically connected to said antenna, said switch turning said antenna ON and OFF to amplitude modulate incoming microwave energy, thereby providing a modulated microwave signal that contains information on the sensed condition; and

a transceiver disposed outside the engine to fill a crankcase of the engine with microwave energy and to separate modulated and continuous-wave signal components of the signal and extract information from the modulated component.

11. A transponder-based microwave telemetry apparatus as set forth in claim 10 wherein said switch comprises a diode.

12. A transponder-based microwave telemetry apparatus as set forth in claim 10 wherein said transponder includes an information gathering circuit electrically connected to said switch.

13. A transponder-based microwave telemetry apparatus as set forth in claim 12 wherein said information gathering circuit comprises either one of a timer and oscillator chip.

14. A transponder-based microwave telemetry apparatus as set forth in claim 10 wherein said of said transponder transmits the modulated signal and receives the microwave energy.

15. A transponder-based microwave telemetry apparatus as set forth in claim 12 wherein said transponder includes a direct current power source electrically connected to said information gathering circuit.

16. A transponder-based microwave telemetry apparatus as set forth in claim 10 including a transmitting antenna electrically connected to said transceiver and extending into the engine.

17. A transponder-based microwave telemetry apparatus as set forth in claim 10 including a receiving antenna electrically connected to said transceiver and extending into the engine.

18. A transponder-based microwave telemetry apparatus for an internal combustion engine comprising:

a transponder disposed inside the engine for measuring a sensed condition of a piston in the engine and providing a modulated microwave signal that contains information on the sensed condition, said transponder comprising a switch, an information gathering circuit, an antenna, and a power source, said switch turning said antenna ON and OFF at a frequency determined by said information gathering circuit to amplitude modulate incoming microwave energy; and

a transceiver disposed outside the engine to fill a crankcase of the engine with the microwave energy and to separate modulated and continuous-wave signal components of the signal and extract information from the modulated component.