The Government of the United States of America, As Represented by the Secretary of Homeland Security

Battelle Memorial Institute

Other

Sra International, Inc.

James Christopher Weatherall

Jeffrey Brian Barber

Barry Thomas Smith

Peter Roland Smith

Duane Karns

Barry H Smith

Joseph A Gatto

Duane Clifford Karns

Zachary J Landicini

A device to determine density includes a housing, a first transducer disposed in the housing at a first position, and a second transducer disposed in the housing at a second position. The second transducer is located a distance from the first transducer. The device also includes a controller that reads a first output from the first transducer, and reads a second output from the second transducer. The controller determines a density of a liquid based on the first output, the second output, and the distance.

Miniature wireless concentration meter and method to determine density and concentration

Miniature wireless concentration meter

An automated resonant waveguide cavity system for determining one or complex permittivity measurements of a sample is provided. The automated resonant waveguide cavity system includes a resonant cavity, a waveguide coupled to the resonant cavity, a programmable network analyzer (PNA) coupled to the waveguide, and a computing device. The computing device includes a memory storing processor executable code for a determination engine and a processor executing the processor executable code to cause the determination engine to obtain data from the PNA. The data is respective to the sample within the resonant cavity. The determination engine further integrates a plurality of analytical and modeling functions in determining the complex permittivity values of the sample from the data.

Automated resonant waveguide cavity system for complex permittivity measurements

A method of using a resonant cavity for measuring a complex permittivity &#x3b5; and identifying of a sample (solid or liquid) of microliter volume size includes using a network analyzer to measure over a defined millimeter wave frequency range, a first resonance frequency at a cavity resonance mode, and calculating an unloaded quality factor of an enclosed resonant waveguide cavity of a defined internal dimensions, placing a sample on a surface of a bottom wall of the resonant waveguide cavity and measure a second resonance frequency and calculating a loaded quality factor; determining, a resonance frequency shift &#x394;f=(f&#x2212;f), determining a complex permittivity &#x3b5; of the sample according to the resonance frequency shift &#x394;f, the loaded quality factor, the unloaded quality factor and the defined internal dimensions; and identifying the sample using a database through the complex permittivity &#x3b5;.

Resonant waveguide cavity system for complex permittivity measurements

The present disclosure is directed to a measurement system for measuring a reflection coefficient of a test sample, including: a transceiver antenna configured to be coupled to a source of electromagnetic radiation; and a RAM positioned between the transceiver antenna and a measurement region of the transceiver antenna, wherein the RAM comprises an aperture substantially orthogonal to and substantially aligned with a transceiving axis of the transceiver antenna. A method for obtaining error correction of a measurement system and a method of measuring a reflection coefficient in a test sample are also provided.

Measurement system and methods of measuring a reflection coefficient

Methods of obtaining error correction for reflection coefficient measurement systems

The present disclosure is directed to an artificial skin having a radar absorbing layer and a conductive layer containing an electrically conductive material, wherein the artificial skin has a reflection coefficient substantially equal to a human skin reflection coefficient, the human skin reflection coefficient being determined at an electromagnetic radiation frequency ranging from 1-500 GHz. A human phantom composed of the artificial skin and methods of testing the contrast resolution sufficiency of and active millimeter wave imaging system using the human phantom are also disclosed.

Artificial skin having a reflection coefficient substantially equal to human skin

In a system that includes a wire grid polarizer, the polarizer is positioned between a thermal illuminator and a thermal emitter such that energy from the thermal illuminator traveling towards the thermal emitter is transformed into linearly polarized energy. In the system, the thermal emitter is configured to reflect at least a portion of the linearly polarized energy towards a millimeter-wave camera and there is a motor coupled with the wire grid polarizer and configured to rotate the polarizer in a manner that varies an apparent temperature of the thermal emitter based on the reflected portion of the linearly polarized energy.

Contrast phantom for passive millimeter wave imaging systems

The present disclosure is directed to an artificial skin including: a radar absorbing layer; a conductive layer comprising at least one material selected from the group consisting of a semiconductive oxide deposited onto a substrate and an electrically conductive polymer, wherein the substrate is in contact with the radar absorbing layer, and wherein the artificial skin has a reflection coefficient substantially equal to a human skin reflection coefficient, the human skin reflection coefficient being determined at an electromagnetic radiation frequency ranging from 1-500 GHz. A human phantom composed of the artificial skin and methods of using the human phantom are also disclosed.

Artificial skin and human phantom for use in active millimeter wave imaging systems

In a system having a thermal backdrop () and a thermal illuminator (), the thermal backdrop includes a body having a top face; a contrast phantom () positioned above the top face and aligned substantially parallel with the top face; and a reflective layer () located between the body and the contrast phantom and aligned substantially parallel with the top face. The thermal illuminator radiates thermal energy () in a first direction towards the contrast phantom; wherein the first direction is aligned with the top face such that when the thermal energy is radiated in the first direction a first portion of the thermal energy is absorbed by the contrast phantom and a second portion () is reflected by the reflective layer towards a millimeter-wave camera () in a second direction. Furthermore, the contrast phantom has a plurality of different portions (A,B,C,D), each portion having a different respective thickness along the first direction.

The present invention pertains to a resonant cavity system, more specifically, a resonant system for measuring the dielectric constant of a sample and its method of use. The system and method provide for holding sample materials, which can be in solid, liquid, or powder form, and for reducing the size of the requisite cavity for measurement. The construction incorporates waveguide flange connectors to seal the electromagnetic cavity, which facilitates the measurement of low-loss materials. The design for signal input enables the use of standard calibration techniques and measurement.

Resonant system and method of determining a dielectric constant of a sample

A contrast phantom for an active millimeter wave imaging system is made from different materials or sections having different reflectivities. The reflectivities incrementally increase in discrete steps so that the phantom is useable to calibrate the active millimeter wave imaging system. The reflectivities preferably range from 0% to 100% and incrementally and linearly increase in equal steps. A method of producing the contrast phantom for the active millimeter wave imaging system is also described.

Development of a contrast phantom for active millimeter wave imaging systems

Described herein is a method by which active millimeter wave radiation may be used to detect and identify the composition of concealed metallic, concealed non-metallic, concealed opaque or concealed semi-transparent materials based on their optical properties. By actively radiating a semi-transparent target anomaly with multiple millimeter wave radiation frequencies, the dielectric properties of the target anomaly can be identified. The dielectric properties of the target anomaly may then be compared to a library of dielectric properties attributed to semi-transparent materials of interest. This method will allow active millimeter wave radiation technology to identify the likely composition of targeted semi-transparent materials through absorption and illumination measurements attributed to the dielectric properties of the targeted composition.

Method for identifying materials using dielectric properties through active millimeter wave illumination

Methods and apparatus are provided for obtaining spatial information about an object, and for measuring the dielectric constant of an object. They include placing the object in a cavity and interacting electromagnetic radiation at a plurality of frequencies with the object to obtain a corresponding plurality of measured resonant transverse magnetic modes. They also include using the plurality of measured resonant transverse magnetic modes to obtain the spatial information for the object, and/or using the plurality of measured resonant transverse magnetic modes to obtain the dielectric constant for the object.

Growing community of inventors

Linwood, NJ, United States of America

James Christopher Weatherall