# US 7,411,392 B2 · Parametric nuclear quadrupole resonance spectroscopy system and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,411,392 B2 - Document ID: US7411392B2 - Status: Granted - Kind: B2 - Application number: 11/698,775 - Filed: 2007-01-26 - Published: 2007-09-27 - Granted: 2008-08-12 - Earliest claimed: 2004-12-22 - Inventors: Larry W. Fullerton - Web page: https://patentgrep.com/patent/US7411392B2 ## CPC - G01R 33/441: {Nuclear Quadrupole Resonance [NQR] Spectroscopy and Imaging} - G01R 33/3621: {NMR receivers or demodulators, e.g. preamplifiers, means for frequency modulation of the MR signal using a digital down converter, means for analog to digital conversion [ADC] or for filtering or processing of the MR signal such as bandpass filtering, resampling, decimation or interpolation} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract A system and method for probing a specimen to determine one or more components by utilizing a first signal to excite the specimen at a nuclear quadrupole resonant frequency and observing changes in a specimen property. One exemplary property may be dielectric constant. Another exemplary property may be magnetic permeability. In one embodiment, the first signal is unmodulated and a second signal is observed for the presence of modulation at the frequency of the first signal. Alternatively, the first signal may be modulated and the second signal may be observed for the presence of the modulation. A system is disclosed wherein the specimen is excited using the first frequency and a radar at the second frequency is used to observe changes in radar reflectivity of the specimen due to the excitation. ## Claims ### Claim 1 A system for probing a specimen to detect a material comprising: a first transmitter, said first transmitter transmitting a first signal, said first signal exciting said specimen at a nuclear quadrupole resonant frequency of said material; said exciting of said specimen at said nuclear quadrupole resonant frequency of said material causing a change in a property of said material; a second transmitter said second transmitter transmitting a second signal, said second signal being directed toward said specimen; said specimen interacting with said second signal and producing a third signal, said third signal being a portion of the energy of said second signal having a change in a signal property resulting from said change in said property of said material; a receiver, said receiver receiving said third signal from said specimen; and a processor, said processor detecting said change in said signal property of said third signal, said change in said signal property of said third signal indicating said specimen comprises said material. ### Claim 2 (depends on 1) The system of claim 1, wherein said third signal is produced by said second signal being transmitted through said material, scattered by said material, or reflected from said material. ### Claim 3 (depends on 1) The system of claim 1, wherein said first signal is unmodulated and said third signal is observed for the presence of modulation at the frequency of the first signal. ### Claim 4 (depends on 1) The system of claim 1, wherein said first signal is modulated and said third signal is observed for the presence of the modulation. ### Claim 5 (depends on 1) The system of claim 1, wherein the first transmitter varies the frequency of said first signal to one or more other nuclear quadurpole resonant frequencies of said material. ### Claim 6 (depends on 1) The system of claim 1, wherein said sample includes at least one other material and wherein the first transmitter varies the frequency of said first signal to a nuclear quadrupole resonance frequency of said at least one other material. ### Claim 7 (depends on 1) The system of claim 1, wherein said specimen comprises one of a piece of baggage, a passenger, a plot of land, or an item on a production line. ### Claim 8 (depends on 1) The system of claim 1, wherein said material comprises an ingredient in a chemical process, a vein of ore, an explosive, an improvised explosive device, a land mine, or a mineral. ### Claim 9 (depends on 1) The system of claim 1, wherein said system is used for at least one of a commercial application, an industrial application, a mining application, a survey application, a security application, or a military application. ### Claim 10 (depends on 1) The system of claim 1, wherein said property of said material comprises a dielectric constant, a magnetic permeability, or a propagation delay through said material. ### Claim 11 (depends on 1) The system of claim 1, wherein at least one of said first transmitter, said second transmitter, said receiver, or said processor is portable. ### Claim 12 A method for probing a specimen to detect a material comprising: transmitting a first signal from a first transmitter, said first signal exciting said specimen at a nuclear quadrupole resonant frequency of said material; said exciting of said specimen at said nuclear quadrupole resonant frequency of said material causing a change in a property of said material; transmitting a second signal from a second transmitter, said second signal being directed toward said specimen; said specimen interacting with said second signal and producing a third signal, said third signal being a portion of the energy of said second signal having a change in a signal property resulting from said change in said property of said material; receiving at a receiver said third signal from said specimen; and detecting said change in said signal property of said third signal, said change in said signal property of said third signal indicating said specimen comprises said material. ### Claim 13 (depends on 12) The method of claim 12, wherein said third signal is produced by said second signal being transmitted through said material, scattered by said material, or reflected from said material. ### Claim 14 (depends on 12) The method of claim 12, wherein said first signal is unmodulated and third signal is observed for the presence of modulation at the frequency of the first signal. ### Claim 15 (depends on 12) The method of claim 12, further comprising: modulating said first signal, wherein said third signal is observed for the presence of said modulation. ### Claim 16 (depends on 12) The method of claim 12, further comprising: changing the frequency of said first signal to one or more other nuclear quadrupole resonant frequencies of said material. ### Claim 17 (depends on 12) The method of claim 12, further comprising: changing the frequency of said first signal to the nuclear quadrupole resonance frequency of at least one other material. ### Claim 18 (depends on 12) The method of claim 12, wherein said specimen comprises a piece of baggage, a passenger, a plot of land, or an item on a production line. ### Claim 19 (depends on 12) The method of claim 12, wherein said material comprises an ingredient in a chemical process, a vein of ore, an explosive, an improvised explosive device, a land mine, or a mineral. ### Claim 20 (depends on 12) The method of claim 12, wherein said property of said material comprises a dielectric constant, a magnetic permeability, or a propagation delay through said material.