The present invention comprises a multi-modal security checkpoint. The security checkpoint can simultaneously scan for and simultaneously identify hidden metallics (e.g., weapons, shrapnel) and non-metallics (e.g., explosives, dielectrics). The security checkpoint performs scanning and identifying at a rate of 15 or more frames per second for all targets within the inspection area. The security checkpoint comprises blocks for sending and receiving radiation signals, the blocks comprising transmitters and/or receivers, the blocks being configured to share information to compare cross- and co-polarizations of signals emitted. The security checkpoint combines many threat detection technologies into one checkpoint that allows it to be robust and detect a large variety of threats in mass transit hubs requiring high throughput processing capabilities.

A system for characterizing a dielectric object situated adjacent to an electrically conductive surface comprises a radiation source configured to radiate electromagnetic energy toward the dielectric object, and a receiver configured to receive scattered electromagnetic energy scattered by the dielectric object and the electrically conductive surface. The system may further comprise a control subsystem, coupled to the radiation source and the receiver, that determines an apparent focal point within the object, determines a phase shift associated with the scattered electromagnetic energy with respect to the electromagnetic energy radiated by the radiation source, and determine a thickness and an index of refraction of the object based, on the apparent focal point and the phase shift. The system may determine the apparent focal point by scanning a calculated focus point of the radiated energy through different depths of the object, and searching for a peak in an amplitude of the scattered energy.

A quasi-optical waveguide apparatus includes a waveguide having a chamber formed by a substantially cylindrical body and configured to propagate terahertz radiation. A plurality of windows are included wherein each window is coupled to a respective end of the waveguide such that the chamber is substantially sealed from the ambient atmosphere. The plurality of windows are transparent to the terahertz radiation.

A drill head for earth boring, in particular for a horizontal drilling device, includes a housing, a transmitter for generating a radio signal, an antenna and a receiver for receiving a reflected radio signal, wherein the transmitter which is adapted to generate the radio signal includes a direct digital synthesizer.

An imaging system includes a first camera and a second camera. A first antenna arrangement collects image light from a first scene as seen by the first camera, and a second antenna arrangement collects image light from a second, different scene as seen by the second camera. The first antenna arrangement includes a first polarized dish antenna and the second antenna arrangement includes a second polarized dish antenna. The first camera and the second camera are supported with a first polarization of the first polarized dish antenna orthogonal to a second polarization of the second polarized dish antenna such that at least some of the image light from the first scene travels through the second polarized dish antenna to reach the first camera and at least some of the image light from the second scene travels through the first polarized dish antenna to reach the second camera.

A millimeter-wave optical imaging system including an imaging detector located at a focal plane of the optical imaging system, the imaging detector being responsive to electromagnetic radiation in wavelength range of approximately 5-50 millimeters, an immersion lens directly coupled to the imaging detector and configured to focus the electromagnetic radiation onto the imaging detector, wherein the focal plane is located on a planar surface of the immersion lens and the imaging detector is directly coupled to the planar surface, a positive power primary mirror configured to reflect the electromagnetic radiation towards the immersion lens, and one of a Fresnel lens or a diffraction grating configured to receive and direct the electromagnetic radiation towards the primary mirror.

One aspect provides a method, including: obtaining sensor data from a ground penetrating radar (GPR) unit; analyzing, using a processor, the sensor data to detect a first object and a second object, the second object being associated with the first object based on location; identifying, with the processor, an underground pipe feature based on the analyzing; associating a position of the underground pipe feature with a location in a pipe network; selecting a subset of the pipe network including a pipe segment associated with the position of the underground pipe feature; and providing the subset of the pipe network as displayable data to a display device. Other aspects are described and claimed.

A method for assessing risk to a marine hydrocarbon recovery operation involves collecting a set of training images and labeling sea surface anomalies on the set of training images. The set of training images and associated labels are used to train a model via backpropagation. A set of non-training images is collected and the trained model is applied to identify a potentially disruptive sea surface anomaly on the set of non-training images. Any risk to the marine hydrocarbon recovery operation by the potentially disruptive sea surface anomaly is then assessed.

A system includes first and second gas cells, each comprising a respective sealed interior waveguide. The first gas cell contains a dipolar gas and the second gas cell does not contain a dipolar gas. The system includes first and second transmit antennas coupled to the first and second gas cells, respectively, to provide first and second electromagnetic waves to the interior of the first and second gas cells, respectively; first receive antenna coupled to the first gas cell to generate a first signal indicative of an amount of energy in the first electromagnetic wave after travel through the first gas cell; second receive antenna coupled to the second gas cell to generate a second signal indicative of an amount of energy in the second electromagnetic wave after travel through the second gas cell; processor configured to calculate a background-free signal based on a difference between the first and second signals.

A millimeter wave image based human body foreign object detection method, comprising: acquiring a millimeter wave gray scale image of a human body; according to a pre-determined foreign object imaging characteristic, extracting from the millimeter wave gray scale image a foreign object area image; according to a pre-determined foreign object image recognition algorithm, performing calculations on the foreign object area image, and acquiring a foreign object image from the foreign object area image; displaying the foreign object image as a foreign object detection result. Also provided is a millimeter wave image based human body foreign object detection system.