METHOD AND APPARATUS FOR SENSING THE PRESENCE OF EXPLOSIVES, CONTRABAND AND OTHER MOLECULES USING NUCLEAR QUADRUPOLE RESONANCE

• US 20110187363A1
• Filed: 12/01/2010
• Published: 08/04/2011
• Est. Priority Date: 01/29/2010
• Status: Active Grant

• Current Assignee: R.A. Miller Industries, Inc.
• Original Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc)
• Inventors: ZANK, Paul A., APOSTOLOS, John T.
• Granted Patent: US 8,742,753 B2
• Time in Patent Office: Days
• US Class Current: 324/307
• CPC Class Codes: G01N 24/084 Detection of potentially hazardous samples, e.g. toxic samples, explosives, drugs, firearms, weapons
• CPC Class Codes: G01R 33/441 Nuclear Quadrupole Resonance [NQR] Spectroscopy and Imaging

Abstract

Stimulated emissions due to nuclear quadropole resonance are detected utilizing a terminated balanced transmission line and a directional coupler for the detection of explosives, contraband, narcotics and the like that exist between the transmission lines, with either a stepped frequency generator utilized to scan between 100 KHz and 10 MHz, or wherein parallel fixed frequency sources are coupled to the transmission line, thereby to permit correlation with expected lines, with the frequency sources being low power so as to not create a safety hazard and so as not to interfere with radiation sensitive devices such as film or electronic circuits that are in the vicinity of the balanced transmission line.

Claims

1. A method for performing a nuclear quadrupole resonance measurement on a material, comprising the steps of:

placing a target material between the elements of a balanced transmission line terminated with a resistive element equal to the impedance of the balanced transmission line;

driving the transmission line through a circulator with a signal having a frequency equal to that of one of the spectral lines of the target material; and

,

detecting the stimulated emission from the target material from an output of the circulator, whereby interference between the drive signal for the transmission line and the received signal from the transmission line is minimized.

2. The method of claim 1, wherein the material includes molecules having a predetermined spectra.

3. The method of claim 2, wherein the frequency at which the balanced transmission line is driven is less than 10 MHz.

4. The method of claim 2, wherein the frequency at which the balanced transmission line is driven is at the low frequency end of the electromagnetic spectrum.

5. The method of claim 4, wherein the low frequency end of the electromagnetic spectrum is above 100 KHz.

6. The method of claim 1, wherein the frequency at which the balanced transmission line is driven is swept from a low frequency to a high frequency.

7. The method of claim 6, wherein the sweeping of the frequency is performed in a step wise fashion.

8. The method of claim 1, wherein the driving step includes the step of simultaneously driving the transmission line with multiple frequencies.

9. The method of claim 8, wherein the multiple frequencies include frequencies which match the stimulated emissions from the target material.

10. The method of claim 1, wherein the signal that drives the balanced transmission line is coded.

11. The method of claim 10, wherein the code is a PN code.

12. The method of claim 1, and further including a multiplicity of transmission lines laid out side by side with each of the transmission lines being driven by a signal that matches the spectral lines of the target material.

13. The method of claim 12, and further including a second set of transmission lines overlying the first set of transmission lines at an angle so as to provide a grid of transmission lines.

14. The method of claim 13, and further including the step of ascertaining the location of the target material by processing the outputs of the grid.

15. The method of claim 1, wherein the driving step includes driving the transmission line with a number of different frequencies matching spectral lines of more than one molecule in the target material, and further including the step of ascertaining from the stimulated emission from the target material the ratio of the components in the target material.

16. The method of claim 1, wherein the balanced transmission line is located at a portal.

17. The method of claim 16, wherein the portal includes one of an access gate, an airline security gate and a border crossing gate.

18. The method of claim 1, wherein the balanced transmission line is incorporated within a shipping container.

19. The method of claim 1, wherein the balanced transmission line surrounds a container.

20. The method of claim 19, wherein the container includes a vehicle.

21. The method of claim 1, wherein the container is a mounted shipboard and includes a transmitter for transmitting the results of the simulated transmission detection.

22. The method of claim 21, wherein the transmitter is part of a mesh network within the ship such that container contents is continuously monitorable by monitoring signals on the mesh network.

23. The method of claim 2, wherein the molecules include an explosive.

24. The method of claim 2, wherein the molecules includes contraband.

25. The method of claim 2, wherein the molecules include at least one drug.

26. The method of claim 25, wherein the drug includes a narcotic.

27. The method of claim 26, wherein the narcotic includes at least one of heroin or cocaine.

28. The method of claim 26, wherein the drug includes pain medication.

29. The method of claim 29, wherein the drug includes Oxycontin.