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Title: Investigation of Wavelet-Based Enhancements to Nuclear Quadrupole Resonance Explosives Detectors

Abstract

Nuclear Quadrupole Resonance (NQR) is effective for the detection and identification of certain types of explosives such as RDX, PETN and TNT. In explosive detection, the NQR response of certain 14N nuclei present in the crystalline material is probed. The 14N nuclei possess a nuclear quadrupole moment which in the presence of an electric field gradient produces an energy level splitting which may be excited by radio-frequency magnetic fields. Pulsing on the sample with a radio signal of the appropriate frequency produces a transient NQR response which may then be detected. Since the resonant frequency is dependent upon both the quadrupole moment of the 14N nucleus and the nature of the local electric field gradients, it is very compound specific. Under DARPA sponsorship, the authors are using multiresolution methods to investigate the enhancement of operation of NQR explosives detectors used for land mine detection. For this application, NQR processing time must be reduced to less than one second. False alarm responses due to acoustic and piezoelectric ringing must be suppressed. Also, as TNT is the most prevalent explosive found in land mines, NQR detection of TNT must be made practical despite unfavorable relaxation tunes. All three issues require improvement inmore » signal-to-noise ratio, and all would benefit from improved feature extraction. This paper reports some of the insights provided by multiresolution methods that can be used to obtain these improvements. It includes results of multiresolution analysis of experimentally observed NQR signatures for RDX responses and various false alarm signatures in the absence of explosive compounds.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Oak Ridge National Lab., TN (United States)
Sponsoring Org.:
Defense Advanced Research Projects Agency, Arlington, VA (United States)
OSTI Identifier:
624024
Report Number(s):
ORNL/CP-96389; CONF-980412-
ON: DE98004124; CNN: N00164-97-C-004; TRN: AD-a340 577
DOE Contract Number:
AC05-96OR22464
Resource Type:
Conference
Resource Relation:
Conference: 12. annual international symposium on aerospace/defense sensing, simulation and controls, Orlando, FL (United States), 13-19 Apr 1998; Other Information: DN: Prepared in collaboration with Quantum Magnetics Inc., San Diego, CA.; PBD: 1998
Country of Publication:
United States
Language:
English
Subject:
44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; 45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE; SIGNALS; SIGNAL-TO-NOISE RATIO; QUADRUPOLE MOMENTS; DETECTION; CHEMICAL EXPLOSIVES; PETN; TNT; MILITARY EQUIPMENT; NUCLEAR QUADRUPOLE RESONANCE; FREQUENCY ANALYSIS; TIME DEPENDENCE; DIGITAL FILTERS; WAVELET TRANSFORMS

Citation Formats

Kercel, Stephen W., Dress, William B., Hibbs, Andrew D., and Barrall, Geoffrey A. Investigation of Wavelet-Based Enhancements to Nuclear Quadrupole Resonance Explosives Detectors. United States: N. p., 1998. Web.
Kercel, Stephen W., Dress, William B., Hibbs, Andrew D., & Barrall, Geoffrey A. Investigation of Wavelet-Based Enhancements to Nuclear Quadrupole Resonance Explosives Detectors. United States.
Kercel, Stephen W., Dress, William B., Hibbs, Andrew D., and Barrall, Geoffrey A. 1998. "Investigation of Wavelet-Based Enhancements to Nuclear Quadrupole Resonance Explosives Detectors". United States. doi:. https://www.osti.gov/servlets/purl/624024.
@article{osti_624024,
title = {Investigation of Wavelet-Based Enhancements to Nuclear Quadrupole Resonance Explosives Detectors},
author = {Kercel, Stephen W. and Dress, William B. and Hibbs, Andrew D. and Barrall, Geoffrey A.},
abstractNote = {Nuclear Quadrupole Resonance (NQR) is effective for the detection and identification of certain types of explosives such as RDX, PETN and TNT. In explosive detection, the NQR response of certain 14N nuclei present in the crystalline material is probed. The 14N nuclei possess a nuclear quadrupole moment which in the presence of an electric field gradient produces an energy level splitting which may be excited by radio-frequency magnetic fields. Pulsing on the sample with a radio signal of the appropriate frequency produces a transient NQR response which may then be detected. Since the resonant frequency is dependent upon both the quadrupole moment of the 14N nucleus and the nature of the local electric field gradients, it is very compound specific. Under DARPA sponsorship, the authors are using multiresolution methods to investigate the enhancement of operation of NQR explosives detectors used for land mine detection. For this application, NQR processing time must be reduced to less than one second. False alarm responses due to acoustic and piezoelectric ringing must be suppressed. Also, as TNT is the most prevalent explosive found in land mines, NQR detection of TNT must be made practical despite unfavorable relaxation tunes. All three issues require improvement in signal-to-noise ratio, and all would benefit from improved feature extraction. This paper reports some of the insights provided by multiresolution methods that can be used to obtain these improvements. It includes results of multiresolution analysis of experimentally observed NQR signatures for RDX responses and various false alarm signatures in the absence of explosive compounds.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1998,
month = 6
}

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