Electromagnetic shielding defect monitoring system and method for using the same

• US 7,459,916 B2
• Filed: 08/30/2006
• Issued: 12/02/2008
• Est. Priority Date: 08/30/2006
• Status: Active Grant

• Current Assignee: L3 Technologies, Inc. (L3Harris Technologies, Inc.)
• Original Assignee: L-3 Communications Corporation (L3Harris Technologies, Inc.)
• Inventors: Lane, Phillip D., Rice, Kelly L., Crain, Charles R., Youngman, James A.
• Primary Examiner(s): Nguyen; Vincent Q.
• Assistant Examiner(s): NGUYEN, HOAI AN D
• Application Number:
  US11/468,755
• Publication Number:
  US 20080074123A1
• Time in Patent Office: 825 Days
• Field of Search: 324/627, 324/612, 324/600, 324/557, 324/718, 324/456, 324/216, 324/237, 324/238, 324/240, 324/217
• US Class Current: 324/627
• CPC Class Codes: G01R 29/0835 Testing shielding, e.g. for efficiency
• CPC Class Codes: G01R 31/001 Measuring interference from external sources to, or emission from, the device under test, e.g. EMC, EMI, EMP or ESD testing measuring electromagnetic fields G01R29/08; circuits for generating HV pulses in dielectric strength testing G01R31/14

Abstract

An embodiment disclosed herein is directed to an electromagnetic shielding defect monitoring system that includes a transmit system adapted to transmit a first electromagnetic field toward a first surface of an electromagnetically shielded enclosure, thereby generating a first current on the first surface, a stationary receive system adapted to detect a second electromagnetic field transmitted from a second surface of the electromagnetically shielded enclosure by a second current induced on the second surface by the first current and to generate a corresponding detected signal; control circuitry adapted to control operations of the transmit and receive systems; and analysis circuitry adapted to identify a location of a defect in the electromagnetically shielded enclosure based upon operations of the transmit and receive systems and based upon the detected signal.

Claims

1. An electromagnetic shielding defect monitoring system, comprising:

a transmit system adapted to transmit a first electromagnetic field toward a first surface of an electromagnetically shielded enclosure, thereby generating a first current on the first surface;

a stationary receive system adapted to detect a second electromagnetic field transmitted from a second surface of the electromagnetically shielded enclosure by a second current induced on the second surface by the first current and to generate a corresponding detected signal;

control circuitry adapted to control operations of the transmit and receive systems; and

analysis circuitry adapted to identify a location of a defect in the electromagnetically shielded enclosure based upon operations of the transmit and receive systems and based upon the detected signal.

2. The electromagnetic shielding defect monitoring system of claim 1, wherein the first surface is an exterior surface of the electromagnetically shielded enclosure and the second surface is an interior surface of the electromagnetically shielded enclosure.

3. The electromagnetic shielding defect monitoring system of claim 1, wherein the first surface is an interior surface of the electromagnetically shielded enclosure and the second surface is an exterior surface of the electromagnetically shielded enclosure.

4. The electromagnetic shielding defect monitoring system of claim 1, wherein the transmit system comprises:

a transmit antenna operably proximate to the first surface of the electromagnetically shielded enclosure and adapted to transmit the first electromagnetic field toward the first surface of the electromagnetically shielded enclosure;

an amplifier adapted to control an amplitude of the first electromagnetic field transmitted by the transmit antenna; and

a spectrum source adapted to control a frequency of the first electromagnetic field transmitted by the transmit antenna.

5. The electromagnetic shielding defect monitoring system of claim 4, wherein the control circuitry is adapted to control an operation of the transmit system by controlling at least one of the amplifier and spectrum source to control at least one of the amplitude and frequency of the first electromagnetic field transmitted by the transmit antenna.

6. The electromagnetic shielding defect monitoring system of claim 1, wherein the transmit system further comprises:

a plurality of transmit antennas each operably proximate to the first surface of the electromagnetically shielded enclosure and adapted to transmit the first electromagnetic field toward the first surface of the electromagnetically shielded enclosure; and

a transmit switching matrix adapted to activate at least one of the plurality of transmit antennas to transmit the first electromagnetic field.

7. The electromagnetic shielding defect monitoring system of claim 6, wherein the control circuitry is adapted to control an operation of the transmit system by controlling which of the plurality of transmit antennas are activated by the transmit switching matrix.

8. The electromagnetic shielding defect monitoring system of claim 1, wherein the receive system comprises:

a receive antenna operably proximate to the second surface of the electromagnetically shielded enclosure and adapted to detect the second electromagnetic field; and

a spectrum analyzer adapted to generate the detected signal based on the second electromagnetic field detected by the receive antenna.

9. The electromagnetic shielding defect monitoring system of claim 1, wherein the receive system comprises:

a plurality of receive antennas each operably proximate to the second surface of the electromagnetically shielded enclosure and adapted to detect the second electromagnetic field; and

a receive switching matrix adapted to activate at least one of the receive antennas to detect the second electromagnetic field.

10. The electromagnetic shielding defect monitoring system of claim 9, wherein the control circuitry is adapted to control an operation of the receive system by selectively coupling a receive antenna to the spectrum analyzer via the receive switching matrix.

11. The electromagnetic shielding defect monitoring system of claim 1, wherein:

the transmit and receive systems are locally or remotely coupled to the control circuitry; and

the receive system is locally or remotely coupled to the analysis circuitry.

12. A computer-implemented method of monitoring electromagnetic shielding defects, comprising:

controlling an operation of a transmit system to transmit a first electromagnetic field toward a first surface of an electromagnetically shielded enclosure, thereby generating a first current on the first surface;

controlling an operation of a stationary receive system to detect a second electromagnetic field transmitted from a second surface of the electromagnetically shielded enclosure by a second current induced on the second surface by the first current;

receiving a detected signal corresponding to the second electromagnetic field; and

identifying a location of a defect in the electromagnetically shielded enclosure based upon operations of the transmit and receive systems and upon the detected signal.

13. The computer-implemented method of monitoring electromagnetic shielding defects of claim 12, wherein the first surface is an exterior surface of the electromagnetically shielded enclosure and the second surface is an interior surface of the electromagnetically shielded enclosure.

14. The computer-implemented method of monitoring electromagnetic shielding defects of claim 12, wherein the first surface is an interior surface of the electromagnetically shielded enclosure and the second surface is an exterior surface of the electromagnetically shielded enclosure.

15. The computer-implemented method of monitoring electromagnetic shielding defects of claim 12, wherein controlling the operation of the transmit system comprises controlling at least one of a frequency and an amplitude of the first electromagnetic field toward the first surface of the electromagnetically shielded enclosure by a transmit antenna comprised within the transmit system.

16. The computer-implemented method of monitoring electromagnetic shielding defects of claim 12, wherein controlling the operation of the transmit system comprises controlling which of a plurality of transmit antennas comprised within the transmit system to activate to transmit the first electromagnetic field toward the first surface of the electromagnetically shielded enclosure.

17. The computer-implemented method of monitoring electromagnetic shielding defects of claim 12, wherein controlling the operation of the receive system comprises selecting which of a plurality of receive antennas comprised within the receive system to detect the second electromagnetic field.

18. The computer-implemented method of monitoring electromagnetic shielding defects of claim 12, further comprising:

locally or remotely controlling the transmit and receive systems; and

locally or remotely identifying the location of the defect in the electromagnetically shielded enclosure.

19. A method of monitoring electromagnetic shielding defects, comprising:

transmitting, from at least one of a plurality of sources, a first electromagnetic field toward a first surface of an electromagnetically shielded enclosure, thereby generating a first current on the first surface;

selecting at least one of a plurality of stationary receive antennas to detect a second electromagnetic field transmitted from a second surface of the electromagnetically shielded enclosure by a second current induced on the second surface by the first current;

generating a detected signal corresponding to the second electromagnetic field; and

identifying a location of a defect in the electromagnetically shielded enclosure based upon the generation of the first electromagnetic field, the detection of the second electromagnetic field, and the detected signal.