511results about "Geological detection using milimetre waves" patented technology

An inspection system that can detect contraband items concealed on, in or beneath an individual's clothing. The system employs mm wave radiation to detect contraband items. The system is described in connection with a check point security system that includes temperature controlled walls to enhance imaging of contraband items. Also, a mm wave camera is used in conjunction with a camera that forms visible images. To address privacy concerns of displaying images of people made with mm wave cameras that effectively “see through” clothes, the mm wave images are not displayed directly. Rather, computer processing produces indications of suspicious items from the underlying raw mm wave images. The indications of suspicious items are overlaid on the visible image.

A security inspection system uses microwave radiation to image targets on a human subject or other item. The system includes an array of antenna elements that are programmable with a respective phase delay to direct a beam of microwave illumination toward a target on the human subject or item. The antenna elements are further capable of receiving reflected microwave illumination reflected from the target. A processor is operable to measure an intensity of the reflected microwave illumination to determine a value of a pixel within an image of the human subject or item. Multiple beams can be directed towards the human subject or item to obtain corresponding pixel values for use by the processor in constructing the image.

A method and apparatus for detecting and classifying an object, including a human intruder. The apparatus includes one or more passive thermal radiation sensors that generate a plurality of signals responsive to thermal radiation. A calculation circuit compares the plurality of signals to a threshold condition and outputs an alarm signal when the threshold condition is met, indicating the presence of the object. The method includes detecting thermal radiation from an object at a first and second wavelength and generating a first and second responsive signal. The signals are compared to a threshold condition that indicates whether the object is an intruder.

Millimeter wave imaging apparatus for use, in articular, as an indoor security system to identify objects concealed under the clothing of a person in a background scene, including means for generating a millimetric temperature contrast between the person to be imaged and the surroundings in scene. This may be a "hot" or "cold" source for producing a flux, and a relatively smaller flux respectively, of incoherent millimeter wavelength radiation. The apparatus may also include at least one partial ellipsoid reflective enclosure for reflecting millimeter wavelength radiation emitted from the "hot" and "cold" source so as to generate non-localized and uniform illumination of the person. The enclosure may have a metallic inner surface on which a dimpled pattern may be embossed to diffuse the millimeter wavelength radiation reflected from the metallic inner surface. The apparatus also includes one or more millimeter wavelength imaging cameras for detecting the millimeter wavelength radiation at one or more millimeter wave center frequencies, which may be mounted inside or outside the reflective enclosure. An image of the objects may be generated on a television monitor from the detected radiation.

The present invention is an inexpensive, hand-held, and easy to operate millimeter-wave detection device that employs a non-imaging sensor which radiates a pulse of millimeter waves of a certain amplitude and frequency towards a target located at a distance from the detection device. The sensor receives pulses of millimeter waves that are reflected from the target and generates a voltage waveform that is characteristic mainly of the target material, while other parameters such as distance to the target are known. The processor of the detection device measures both the peak voltage and the rate of increase of the voltage until it reaches the maximum. Using an algorithm stored in a software module, the deviation between the rate of the voltage rise and the peak voltage is compared with values of similar parameters for a number of test targets made of different materials that were previously collected and stored in a calibration table in the memory of the device. A concealed object, e.g. a weapon, is positively identified when the measured voltage rise is found to be similar to one of the stored voltage rises. The circuitry of the detection device generates a visual and / or audio output to a display device which is indicative to the operator as to whether a concealed object is present and, if a match is found with the data in the calibration table, the nature of the concealed object is also displayed. In addition to the basic mode of operation described, various other operation modes can be employed with the detection device of the invention.

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.

A millimeter wave imaging system that includes at least one millimeter wave frequency scanning antenna for collecting frequency dependent beams of millimeter wave radiation from a narrow one-dimensional field of view. The collected radiation is amplified at the collected frequencies and the amplified signals are separated into frequency dependent bins with a tapped-delay beam-former. These bins are then sampled to produce a one-dimensional image of the antenna field of view. A two dimensional image of a target may be obtained by moving the target across the field of view of the scanning antenna. In a preferred embodiment the antenna is only 4.5 inches in length and constructed from WR-10 waveguide with inclined slots cut in one of the narrow walls at 79 mil spacings. This geometry creates a frequency-scanned antenna spanning a 20 degree vertical field of view over a 75.5-93.5 GHz operational band of the sensor, starting at approximately 1 degree below horizontal at 93.5 GHz and ranging to approximately 21 degrees below horizontal at 75.5 GHz. In this embodiment 64 of these antenna elements are arranged in four stacks of 16 antennas focused at about 18 inches to construct a portal contraband screener.

A microwave imaging system suppresses sidelobes in a microwave image captured using a sparse antenna array using an illumination system that operates in two different illumination modes. The antenna array including subarrays of antenna elements arranged in a sparse geometry to form complementary subarray patterns. The illumination system operates in a first mode to transmit microwave illumination to both of the complementary subarray patterns of the antenna array and receive reflected microwave illumination from both of the complementary subarray patterns of the antenna array to produce a first receive signal. The illumination system further operates in a second mode to transmit microwave illumination to a first one of the complementary subarray patterns of the antenna array and receive reflected microwave illumination from a second one of the complementary subarray patterns of the antenna array to produce a second receive signal. Sidelobes are suppressed using a linear combination of the first and second receive signals.

A microwave imaging system suppresses sidelobes in a microwave image captured using a sparse antenna array using an illumination system that operates in two different illumination modes. The antenna array including subarrays of antenna elements arranged in a sparse geometry to form complementary subarray patterns. The illumination system operates in a first mode to transmit microwave illumination to both of the complementary subarray patterns of the antenna array and receive reflected microwave illumination from both of the complementary subarray patterns of the antenna array to produce a first receive signal. The illumination system further operates in a second mode to transmit microwave illumination to a first one of the complementary subarray patterns of the antenna array and receive reflected microwave illumination from a second one of the complementary subarray patterns of the antenna array to produce a second receive signal. Sidelobes are suppressed using a linear combination of the first and second receive signals.

A method for inspecting a package to identify an object concealed in the package includes passing two beams of THz-radiation through the package. The frequency of THz radiation in one beam is different from that in the other, and the beams are at an angle to each other. Each of the transmitted beams is used to form an image of the package and the object. The absorption coefficient of the object is determined from the two images. The material of the object is determined from the absorption coefficients at the two frequencies. The method is useful for detecting explosive material concealed in baggage.

An inspection system uses microwave radiation to capture a microwave image of a transportable item. The system includes a transmit scanning panel including a transmit array of transmit antenna elements, each being programmable with a respective phase delay to direct a transmit beam of microwave radiation toward a target of the transportable item for transmission of the microwave radiation through the target. The system further includes a receive scanning panel including a receive array of receive antenna elements, each being programmable with a respective phase delay to receive a receive beam of microwave radiation from the target. A processor measures the amplitude and phase of the microwave radiation in the receive beam to determine a relative value of a pixel within the microwave image of the transportable item based on a reference value of the pixel.

Methods and apparatuses for detecting, locating, and identifying microwave transmitters and receivers at distant locations are disclosed. First and second electromagnetic beams at first and second frequencies, respectively, are transmitted in first and second directions. The second frequency is offset from the first frequency to define an interference difference frequency. As such, the first and second electromagnetic beams interfere at a far field distance corresponding to an intersection of the first and second electromagnetic beams. In the far field the beams interfere with microwave devices that reradiate a return radiation at the difference frequency. The methods and apparatuses detect the return radiation at the difference frequency, such as by way of a receiver, and locate the interference zone to determine the location of the microwave device, such as by a processor.

Scanning apparatus which may be used in a real-time passive millimeter wavelength imaging system or in other radiometry systems. The apparatus scans input radiation from a scene and output radiation is transmitted to a receiver system, for example a millimeter wave imaging camera or a radar receiver. The apparatus comprises a rotatable reflective plate having an axis of rotation passing through the centre of its surface and a lens arrangement for selectively transmitting and focusing radiation having a particular direction of polarisation. The apparatus may also comprise a feed horn array comprising a plurality of feed horns, the feed horns forming part of a spherical surface having a radius of curvature substantially equal to R / 2 and being concentric with the third substantially spherical polarising element. The apparatus may further comprise a detector array comprising a plurality of detector elements. The detector array may form part of a millimeter wave imaging camera.

A surveillance system is disclosed. In some embodiments, the surveillance system may include at least one controller adapted to control operation of first and second screening apparatus and to produce image data and screening data, to relate the image data to the screening data, and to produce relational information data from the related image data and screening data. In some embodiments, the system may include a first screening apparatus adapted to screen a subject in a subject position, a second screening apparatus adapted to screen the subject in the subject position, and a controller adapted to produce first and second screening data from the first and second screening apparatus, respectively, relate the first and second screening data, and to produce relational information data from the related first and second screening data.

The invention belongs to the technical filed of security inspection and relates to a vertical mechanical microwave scanning active imaging personnel security inspection system. By means of creative design and through adoption of a pair of horizontal detection arrays which are separately arranged in parallel on two sides or the front side and the back side of an inspected person in a vertical mode, vertical scanning imaging for the inspected person is conducted. Each detection array is in a shape of a straight array or a bow shape with two inwards folded heads or an arc shape or the like. Compared with an existing adopted vertical detection array active imaging personnel security inspection system, the vertical mechanical microwave scanning active imaging personnel security inspection system has the advantages that the number of transmit-receive components of the detection arrays can be reduced greatly and a system structure is simplified. Not only is convenience brought to storage, transportation, installation and usage but also system cost can be reduced.

A method of scanning a shoe. The method comprises directing from a source at least one first signal at the shoe, the at least one first signal comprising substantially millimetre and / or microwave radiation, receiving at one or more receivers a plurality of second signals, the plurality of second signals comprising reflections of the at least one first signal from different positions with the shoe. The method further comprises processing each of the second signals to determine a plurality of reflection positions within the shoe and processing the plurality of second signals and reflection positions to generate second data, the second data indicating a composition of the shoe.

A millimeter wave imaging system that includes at least one millimeter wave frequency scanning antenna for collecting frequency dependent beams of millimeter wave radiation from a narrow one-dimensional field of view. The collected radiation is amplified at the collected frequencies and the amplified signals are separated into frequency dependent bins with a tapped-delay beam-former. These bins are then sampled to produce a one-dimensional image of the antenna field of view. A two dimensional image of a target may be obtained by moving the target across the field of view of the scanning antenna. In a preferred embodiment the antenna is only 4.5 inches in length and constructed from WR-10 waveguide with inclined slots cut in one of the narrow walls at 79 mil spacings. This geometry creates a frequency-scanned antenna spanning a 20 degree vertical field of view over a 75.5–93.5 GHz operational band of the sensor, starting at approximately 1 degree below horizontal at 93.5 GHz and ranging to approximately 21 degrees below horizontal at 75.5 GHz. In this embodiment 64 of these antenna elements are arranged in four stacks of 16 antennas focused at about 18 inches to construct a portal contraband screener. In another preferred embodiment called the single stick imager, the antenna is 24 inches long with 300 inclined slots serving as receive apertures.

Methods and apparatus for scanning articles, such as footwear, to provide information regarding the contents of the articles are described. According to one aspect, a footwear scanning system includes a platform configured to contact footwear to be scanned, an antenna array configured to transmit electromagnetic waves through the platform into the footwear and to receive electromagnetic waves from the footwear and the platform, a transceiver coupled with antennas of the antenna array and configured to apply electrical signals to at least one of the antennas to generate the transmitted electromagnetic waves and to receive electrical signals from at least another of the antennas corresponding to the electromagnetic waves received by the others of the antennas, and processing circuitry configured to process the received electrical signals from the transceiver to provide information regarding contents within the footwear.

A method for imaging test objects by millimeter waves, especially for checking individuals for suspicious objects is provided, whereby the test object is gradually irradiated with millimeter waves along its circumference and the scattered waves are received and evaluated in order to display an image of the test object. A viewing direction of the transmitting area and a direction of reception of the receiving area extend at an angle of 15° to 70°, preferably 20° to 35° to the longitudinal axis of the test object. For evaluation of the scattered waves in the direction of the longitudinal axis of the test object, a pulse radar or FMCW radar technology is used, and for evaluation at an angle to the longitudinal axis, SAR technology is used.

The field of the invention is that of devices for detecting objects concealed on human subjects. These devices are more particularly dedicated to the surveillance and protection of airport areas and transport airplanes. Currently, the devices rely either on X-ray detection or on microwave imaging. In the former case, the system can prove hazardous to human beings, and in the other case, the device raises ethical problems. The invention proposes a device whose operation relies on the reflective properties of the microwave signals polarized by the suspect objects that we are seeking to detect. This device can be portable or installed on security gates. This technique is simple to design, inexpensive, does not require any great computing power and is very well suited to the objects to be detected. The complete measurement is extremely quick and requires no sophisticated measuring instrument.

The present invention discloses a millimetre wave three dimensional holographic scan imaging apparatus and a method for inspecting a human body or an article. The apparatus comprises a first millimetre wave transceiver module, a second millimetre wave transceiver module, a first guide rail device to which the first millimetre wave transceiver module is connected in slidable form, a second guide rail device to which the second millimetre wave transceiver module is connected in slidable form, and a driver configured to drive the first / second millimetre wave transceiver module to move along the first / second guide rail device, wherein the first scan performed by the first millimetre wave transceiver module and the second scan performed by the second millimetre wave transceiver module both are plane scans. They may improve scan speeds and accuracy, simplify scan operations and enhance the flexibility of the apparatus.

Provided are methods of using electromagnetic waves for detecting metal and / or dielectric objects. Methods include directing microwave and / or mm wave radiation in a predetermined direction using a transmission apparatus, including a transmission element; receiving radiation from an entity resulting from the transmitted radiation using a detection apparatus; and generating one or more detection signals in the frequency domain using the detection apparatus. Methods may include operating a controller, wherein operating the controller includes causing the transmitted radiation to be swept over a predetermined range of frequencies, performing a transform operation on the detection signal(s) to generate one or more transformed signals in the time domain, and determining, from one or more features of the transformed signal, one or more dimensions of a metallic or dielectric object upon which the transmitted radiation is incident. A system and method for remote detection and / or identification of a metallic threat object using late time response (LTR) signals is also disclosed.

A millimeter wave three dimensional holographic scan imaging apparatus and a method for inspecting an object to be inspected using the same are disclosed. The apparatus includes a millimeter wave transceiver module with a millimeter wave transceiver antenna array for transmitting and receiving a millimeter wave signal. The apparatus also includes a guide rail device, to which the millimeter wave transceiver module is connected in slidable form. The millimeter wave transceiver module is moveable along the guide rail device to perform a plane scan on an object to be inspected. A data processing device generates a millimeter wave holographic image from the plane scan.

The invention belongs to the safety check technology field and particularly relates to a motion human body safety check imaging system and method. The system comprises a synthetic aperture radar (SAR) subsystem, a tracking positioning subsystem and a central processing subsystem, wherein the SAR subsystem is used for carrying out microwave or millimeter wave SAR imaging for a human body in motion, the tracking positioning subsystem is used for tracking and positioning the human body and parts of the human body to acquire the three-dimensional position and attitude information at any time, the central processing subsystem is used for controlling the whole system, processing the acquired data, displaying processing results to users and especially carrying out focusing imaging of the original data acquired by the SAR subsystem through utilizing the position and attitude information of the human body and the parts acquired by the tracking positioning subsystem to acquire SAR images of the human body or the parts. The system is advantaged in that the system aims to realize automatic detection on security threats and prohibited articles carried out by people, and the method is applicable to busy flow public facility and public party and border port occasions.

Scanning apparatus which scans input radiation from a scene and output radiation is transmitted to a receiver system, for example a millimetre wave imaging camera or a radar receiver by a rotatable reflective plate having an axis of rotation passing through the centre of its surface, secondary reflector and static reflector, wherein the secondary reflector is a second rotatable reflective plate having a common axis of rotation with the first rotatable reflective plate, wherein the common axis of rotation is inclined at a non-zero zero angle thetab to the normal to the second reflective plate. The normal to the first rotatable plate is inclined at a small angle to the common axis of rotation, typically a few degrees and forms the secondary reflector. The static reflector may be a polarising roof reflector through which radiation is input to and output from the apparatus. The apparatus also includes a 45° Faraday rotator or a birefringent surface such as a Meander-line. An additional Faraday rotator and an inclined polariser may be included in the apparatus and arranged such that radiation output to the receiver system may be separated from the path of input radiation. Alternatively, the scanning apparatus may include a reflector lens arrangement, such that focused output radiation may be output directly to the receiver system.

Active millimeter-wave imaging systems can include an antenna apparatus configured to transmit toward and receive from a subject in a subject position, electromagnetic radiation. A controller can include a transceiver configured to operate the antenna apparatus and produce an output representative of the received radiation, and a processor adapted to convert the transceiver output into image data representative of an image of the subject. The antenna apparatus may move in a partial or continuous loop around the subject, toward or away from the subject, or in an opposite direction to an associated antenna apparatus. Antenna units in the antenna apparatus may be oriented at different angular positions along an array. Antenna arrays may also be formed of a plurality of array segments, and a group of arrays may be combined to form an antenna apparatus.

A microwave imaging system uses microwave radiation provided by a microwave source to image targets. The system includes an array of antenna elements that are capable of being programmed with a respective transmission coefficient to direct the microwave illumination from the microwave source toward a position on the target. The antenna elements are further capable of being programmed with a respective additional transmission coefficient to receive reflected microwave illumination reflected from the position on the target and direct the reflected microwave illumination towards a microwave receiver. A processor is operable to measure an intensity of the reflected microwave illumination to determine a value of a pixel within an image of the target. Multiple beams can be directed towards the target to obtain corresponding pixel values for use by the processor in constructing the image.

The invention provides for an expandable multi channel radiometer imaging method and system. The imaging system includes a scanner for reflecting millimeter wave energy emanating from a pre-determined scene. The millimeter wave energy is focused to a focal plane array using an optical lens and a multi channel radiometer receives the millimeter wave energy. The focal plane array is formed by a plurality of pixels that each includes a single low noise amplifier. The number of pixels of the focal plane array is expendable to increase the resolution of a millimeter wave image. A virtual grid of cells is formed representing different values of millimeter wave energy within the imaging zone. Algorithms calculate differences of millimeter wave energy between cells of said virtual grid to display a composite image to identify concealed objects on an individual.