Technologies applicable to NMR spin-echo amplitude estimation are disclosed. Example methods may calibrate for distortion of a shape and estimated amplitude of measured NMR spin or gradient echoes. NMR spin or gradient echo measurements may be performed on a sample. The measured NMR spin or gradient echoes may be used to calculate an echo-shape calibration factor. The echo-shape calibration factor may estimate an effect of echo shape on estimated spin or gradient echo amplitude(s) of the NMR spin or gradient echoes. The echo-shape calibration factor may be used to correct for underestimation or overestimation of the spin or gradient echo amplitude(s).

A transmission line array is used for explosive/contraband detection using nuclear quadrupole resonance in which the array is driven in-phase with synchrony frequency-swept signals. Each of the balanced transmission lines is fed with a low power swept frequency source and stimulated emissions are picked out with a directional coupler. Location is provided using a cross grid array or a phase detector is used for each balanced line, with phase determining the distance to the sensed substance.

A system includes a table and a material detection system. The material detection system includes a transmit chain configured to generate first radio frequency (RF) signals and a transmit probe configured to transmit the first RF signals towards an item through open space. The material detection system also includes a receive probe configured to receive second RF signals from the item through open space, where the second RF signals have one or more characteristics indicative of one or more materials within the item. The material detection system further includes a receive chain configured to process the second RF signals and at least one processing device configured to identify the one or more materials within the item using nuclear quadrupole resonance (NQR) spectrometry based on the processed second RF signals. The transmit and receive probes are positioned in an upper portion of the table.

A system includes a table and a material detection system. The material detection system includes a transmit chain configured to generate first radio frequency (RF) signals and a transmit probe configured to transmit the first RF signals towards an item through open space. The material detection system also includes a receive probe configured to receive second RF signals from the item through open space, where the second RF signals have one or more characteristics indicative of one or more materials within the item. The material detection system further includes a receive chain configured to process the second RF signals and at least one processing device configured to identify the one or more materials within the item using nuclear quadrupole resonance (NQR) spectrometry based on the processed second RF signals. The transmit and receive probes are positioned in an upper portion of the table.

Systems and methods for pre-tuning a main Nuclear Quadrupole Resonance (NQR) probe using a forward sensing probe include a determination of an amount of resonance detuning of the forward sensing probe caused by a moving object entering a field of view of the forward sensing probe. The amount of resonance detuning is used to pre-tune the main probe such that when the moving object enters a field of view of the main probe, the main probe will move back into tune while delivering optimal power to the object for measurement and identification of a material therein.

Systems and methods are described, and one method includes illuminating a target-of-interest (TI) with an RF energy configured to effect, over a time duration extending from a first time to a second time, an increase in a temperature of the TI. At a first detection time within the time duration, a first temperature NQR signal spectrum of the TI is detected, and a corresponding first temperature NQR spectrum data set is generates. At a second detection time, subsequent to the first detection time, a second temperature NQR signal spectrum of the TI is detected and corresponding second temperature NQR spectrum data set is output. Based at least in part on the first temperature NQR spectral dataset and the second temperature NQR spectral dataset, the TI is classified between including the SI and not including the SI.

Apparatus for the measurement of ore in mine haul vehicles is disclosed, the apparatus comprising: a portal, defining a portal zone, wherein a haul vehicle carrying ore is positionable in or movable through the portal zone; and at least one magnetic resonance (MR) sensor comprised in the portal. The MR sensor includes a main loop and a drive loop located above the main loop. A magnetic resonance sensor control system is provided and configured to control at least one of: the positioning of the at least one MR sensor relative to the portal zone and/or ore burden; the positioning of elements comprised in the MR sensor relative to each other; electromagnetic suppression characteristics of the at least one MR sensor; and/or sensitivity of the at least one MR sensor as a function of distance of the sensor from the ore burden.

A system/device, such as a gradiometer probe for detecting RF signals, or for example for explosive detection, has the shape of the coils in its adjustment mechanism that minimizes the cross-talk between the receiver probe (Rx) and the transmitting antenna (Tx) in such a way as to minimize (or reduce) the areas where the distance between the coils during the adjustment is the smallest. Moving coils along the plain of the coils is one mechanism of achieving it. Having the coils of different shapes, e.g., circular receiver and oval transmitter coils, is another. Many shapes are possible, including circular, oval, elliptical, and polygonal, to give a few examples. In some embodiments both of these methods/approaches are combined in a single device.

A device is for checking the authenticity of an areal data carrier having a zero-field nuclear magnetic resonance feature, having one or more excitation coils for producing excitation pulses for the zero-field NMR feature, an array of multiple receiver coils that are independent of the excitation coils and are at least partially arranged adjacent to each other for the spatially resolved detection of the signal response of the zero-field NMR feature, the number of receiver coils in the receiver coil array being greater than the number of excitation coils, and the area covered by the excitation coils at least partially covering the area covered by the receiver coils in the receiver coil array and exceeding the size of said area.

An exemplary integrated nuclear quadrupole resonance-based detection system comprises a front-end device having a hand-held form factor, wherein the front-end device is configured to scan a sample in or near a sample coil using inbuild electronics and acquire a nuclear quadrupole resonance measurement. The system further includes a swappable sample coil that is attached to an opening at a face of the front-end device and is tuned to a resonant frequency of the sample; and a swappable impedance matching network that is attached to the opening at the face of the front-end device and is configured to tune the resonant frequency of the sample coil. The inbuild electronics comprises a wireless transfer module that is configured to communicate the acquired nuclear quadrupole resonance measurement with a back-end device of the integrated nuclear quadrupole resonance-based detection system. Other systems and methods are also provided.