Abstract:
Method and apparatus for detecting objects. In one embodiment, a person entering a secured zone is illuminated with low-power polarized radio waves. Differently polarized waves which are reflected back from the person are collected. Concealed weapons are detected by measuring various parameters of the reflected signals and then calculating various selected differences between them. These differences create patterns when plotted as a function of time. Preferably a trained neural network pattern recognition program is then used to evaluate these patterns and autonomously render a decision on the presence of a weapon. An interrupted continuous wave system may be employed. Multiple units may be used to detect various azimuthal angles and to improve accuracy.
Abstract:
A system and method for detecting dangerous objects and substances are disclosed. According to one embodiment, a method comprises generating a microwave signal that is reflected by a target to render one or more reflected signals. The one or more reflected signals are received at an antenna array. The one or more reflected signals are converted into digital reflected signals. The microwave signal is converted into a digital signal. The digital reflected signals and the digital signal are processed to determine the three dimensional position of the target. The digital reflected signals and the digital signal are processed to identify the target. The digital reflected signals and the digital signal are processed to determine a state of the target; and determine whether the target is a dangerous object.
Abstract:
A method and apparatus are disclosed for forming an image from millimeter waves. A field of view scanned using two geometrically orthogonal, intersecting copolarized fan beams (110, 120) to receive millimeter wave radiation. The received millimeter wave radiation from said fan beams are then cross-correlated (250, 650). Also, a method and antenna (400, 610) for receiving millimeter wave radiation are disclosed. The antenna includes first and second fan beam antennas (410, 420) for receiving millimeter wave radiation and a filter (430, 440) for rotating polarization of incident millimeter wave radiation through 90 degrees received by the second fan beam antenna (410). The respective first and second beams (110, 120) intersect and are co-polarized and geometrically orthogonal to each other. Still further, a millimeter wave imaging system (600) and method are also disclosed, which utilise an antenna (610) for receiving millimeter wave radiation, process the received millimeter wave radiation from the antenna (610), and build up the image (682) using a filtered, cross-correlated signal.
Abstract:
The system and method for standoff detection of human carried explosives (HCE) automatically detects HCE (112) up to a range of (200) meters and within seconds alerts an operator to HCE (112) threats. The system (100) has radar only, or both radar and video sensors, a multi-sensor processor (102), an operator console (120), handheld displays (122), and a wideband wireless communications link. The processor (102) receives radar and video feeds and automatically tracks and detects all humans (110) in the field of view. Track data continuously cues the narrow beam radar (118) to a subject of interest (110), (112) the radar (106), (108) repeatedly interrogating cued objects (110), (112), producing a multi-polarity radar range profile for each interrogation event. Range profiles and associated features are automatically fused over time until sufficient evidence is accrued to support a threat/non-threat declaration hypothesis. Once a determination is made, the system (100) alerts operators through a handheld display (122) and mitigates the threat if desired.
Abstract:
In accordance with one embodiment of the present invention, a millimeter or sub-millimeter wave portal system is provided. Generally, the portal system comprises an electrooptic source and one or more millimeter or sub-millimeter wave detectors. The electrooptic source comprises an optical signal generator, optical switching and encoding circuitry, and one or more optical/electrical converters. Additional embodiments are disclosed and claimed.
Abstract:
An illumination source of predominantly non-directional and incoherent millimeter-wave radiation for illuminating an area for passive millimeter-wave imaging comprises a container with at least a partly reflective internal surface and a plurality of exit apertures and a primary source of millimeter-wave radiation for emitting millimeter-wave radiation into the container. The primary source and the container are arranged so that a proportion of the millimeter-wave radiation emitted by the source undergoes reflection within the container before being emitted through the apertures, such that the different paths lengths are at least equal to the coherence length of the radiation. This is facilitated if the bandwidth of the radiation is preferably at least 1 GHz. The container may be a box in which a waveguide is used to couple radiation from the primary source into the box. Alternatively, the container may be formed from a mesh and the plurality of holes is provided by the holes in the mesh.
Abstract:
Disclosed herein are exemplary embodiments of imaging systems and methods of using such systems. In one exemplary embodiment, one or more direct images of the body of a clothed subject are received, and a motion signature is determined from the one or more images. In this embodiment, the one or more images show movement of the body of the subject over time, and the motion signature is associated with the movement of the subject's body. In certain implementations, the subject can be identified based at least in part on the motion signature. Imaging systems for performing any of the disclosed methods are also disclosed herein. Furthermore, the disclosed imaging, rendering, and analysis methods can be implemented, at least in part, as one or more computer-readable media comprising computer-executable instructions for causing a computer to perform the respective methods.
Abstract:
One embodiment of the present invention includes scanning a target with electromagnetic radiation including one or more frequencies in a range of about 200 MHz to about 1 THz; establishing a point cloud representation of the surface of the target from the scan; and performing one or more curve-fitting operations as a function of at least a portion of the points of the point cloud representation to represent at least a portion of the surface of the target.
Abstract:
An interrogating system can include an interrogating apparatus configured to transmit toward and receive from a subject in a subject position, millimeter-wave electromagnetic radiation. Such a system can also include a controller configured to operate the interrogating apparatus, and produce data representative of a characteristic of the subject from received radiation. Some embodiments of such an interrogating system may include interrogating apparatus adapted to be mounted to a vehicle or at a vehicle loading zone, to interrogate passengers and/or other persons prior to boarding or accessing the vehicle. Such embodiments may include one or more controllers positioned within the vehicle or at the loading zone.
Abstract:
A surveillance system can include a first sensor apparatus configured to interrogate a subject, including a person and objects carried by the person, with millimeter-wave electromagnetic radiation for imaging the subject. A supplemental source provides additional information about the subject that is relatable to objects potentially carried by the person. Relational information relates the produced image signal and the subject information. The supplemental source may be a second sensor apparatus adapted to detect a given characteristic of an object potentially carried by a person in the subject position. Relational information about whether the person is carrying an object having the given characteristic may then be produced.