CN117538948A - Millimeter wave imaging device, security inspection device and security inspection method - Google Patents
Millimeter wave imaging device, security inspection device and security inspection method Download PDFInfo
- Publication number
- CN117538948A CN117538948A CN202311808561.XA CN202311808561A CN117538948A CN 117538948 A CN117538948 A CN 117538948A CN 202311808561 A CN202311808561 A CN 202311808561A CN 117538948 A CN117538948 A CN 117538948A
- Authority
- CN
- China
- Prior art keywords
- millimeter wave
- array
- millimeter
- imaging device
- inspected object
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000003384 imaging method Methods 0.000 title claims abstract description 98
- 238000007689 inspection Methods 0.000 title claims abstract description 53
- 238000000034 method Methods 0.000 title claims description 13
- 238000001514 detection method Methods 0.000 claims description 10
- 230000001678 irradiating effect Effects 0.000 claims description 4
- 238000003491 array Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 238000005259 measurement Methods 0.000 description 6
- 230000003287 optical effect Effects 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000002310 reflectometry Methods 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000003032 molecular docking Methods 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- WLRMANUAADYWEA-NWASOUNVSA-N (S)-timolol maleate Chemical compound OC(=O)\C=C/C(O)=O.CC(C)(C)NC[C@H](O)COC1=NSN=C1N1CCOCC1 WLRMANUAADYWEA-NWASOUNVSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 230000005670 electromagnetic radiation Effects 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000037368 penetrate the skin Effects 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V8/00—Prospecting or detecting by optical means
- G01V8/005—Prospecting or detecting by optical means operating with millimetre waves, e.g. measuring the black losey radiation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
- G01S13/90—Radar or analogous systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques, e.g. synthetic aperture radar [SAR] techniques
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
- G01S13/90—Radar or analogous systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques, e.g. synthetic aperture radar [SAR] techniques
- G01S13/9021—SAR image post-processing techniques
- G01S13/9023—SAR image post-processing techniques combined with interferometric techniques
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/41—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
- G01S7/411—Identification of targets based on measurements of radar reflectivity
Landscapes
- Engineering & Computer Science (AREA)
- Remote Sensing (AREA)
- Radar, Positioning & Navigation (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- Electromagnetism (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geophysics (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The present disclosure provides a millimeter wave imaging device and a security inspection device. The millimeter wave imaging device includes a millimeter wave transceiving array and a reflecting plate configured to be opposed to the millimeter wave transceiving array. The millimeter wave imaging device is capable of constructing a holographic image of a subject of an object under inspection based on received millimeter waves reflected back from a surface of the object under inspection, and reproducing a three-dimensional image of the subject of the object under inspection based on the constructed holographic image of the subject; and the millimetric wave imaging device is also capable of constructing a holographic image of the side portion of the inspected object based on the millimetric wave reflected back from the reflecting plate and reproducing a three-dimensional image of the side portion of the inspected object based on the constructed holographic image of the side portion, thereby determining whether the inspected object contains other articles.
Description
Technical Field
The present disclosure relates to the field of security inspection technology. In particular, it relates to a millimeter wave imaging device, a security inspection device and a security inspection method.
Background
In China, the application of millimeter wave human body imaging security inspection equipment is expanding continuously, and plays a positive role in occasions involving personnel security inspection and examination, including civil aviation airports, customs, ports, important places, major activities and the like. The millimeter wave human body security inspection equipment has the advantages of wide inspection range, high speed, good experience and non-contact and digital working modes, so that the millimeter wave human body security inspection equipment becomes the preference of various intelligent security.
However, the existing millimeter wave human imaging devices all have areas with poor imaging effects caused by poor coverage effects of millimeter wave receiving and transmitting signals, such as areas of waist, shoulders, leg sides and the like of a human body, and even generate imaging blind areas in millimeter wave images, if the areas have articles with weak reflectivity for millimeter waves or absorbing millimeter waves or the orientation range of the millimeter waves reflected by the articles is limited, the areas are not received by a receiving antenna, and thus missed detection is easy to cause.
There is a need for further improving millimeter wave security inspection equipment, improving inspection accuracy, and reducing missed inspection.
Disclosure of Invention
An object of the present disclosure is to propose a millimeter wave imaging device comprising:
the millimeter wave receiving and transmitting array is used for transmitting millimeter waves and receiving the reflected millimeter waves; and
a reflection plate configured to be opposed to the millimeter wave transceiving array and to be moved in synchronization with the millimeter wave transceiving array so as to be capable of reflecting a part of millimeter waves emitted from the millimeter wave transceiving array to a side portion of an inspected object, and a reflected signal being capable of being reflected back to the reflection plate via the side portion of the inspected object, the reflection plate being capable of reflecting millimeter waves reflected back by the side portion of the inspected object to the millimeter wave transceiving array;
The millimeter wave receiving and transmitting array and the reflecting plate define an inspection channel, and the surface of an inspected object positioned on the inspection channel reflects millimeter waves emitted by the millimeter wave receiving and transmitting array back to the millimeter wave receiving and transmitting array;
wherein the millimetric wave imaging device is capable of constructing a holographic image of a subject of the inspected object based on the received millimetric wave reflected back from the surface of the inspected object and reproducing a three-dimensional image of the subject of the inspected object based on the constructed holographic image of the subject; and the millimeter wave imaging device is capable of constructing a hologram image of a side portion of an inspected object based on the millimeter wave reflected back from the reflection plate, and reproducing a three-dimensional image of the side portion of the inspected object based on the constructed hologram image of the side portion, thereby determining whether the inspected object contains other articles.
In an exemplary embodiment of the present disclosure, the reflecting plate forms an angle of 0 to 90 degrees with the millimeter wave transceiver array.
In an exemplary embodiment of the present disclosure, the millimeter wave transceiver array includes a first millimeter wave transceiver array located at a first side of the inspection tunnel and a second millimeter wave transceiver array located at a second side of the inspection tunnel opposite the first side, the reflection plate includes at least one first reflection plate disposed in correspondence with the second millimeter wave transceiver array and at least one second reflection plate disposed in correspondence with the first millimeter wave transceiver array; the at least one first reflecting plate can reflect part of millimeter waves emitted by the second millimeter wave receiving and transmitting array to the side part of the inspected object, and can reflect millimeter waves reflected by the side part of the inspected object back to the second millimeter wave receiving and transmitting array; the at least one second reflecting plate can reflect a part of the millimeter waves emitted by the first millimeter wave transmitting-receiving array to the side part of the inspected object, and can reflect the millimeter waves reflected by the side part of the inspected object back to the first millimeter wave transmitting-receiving array.
In an exemplary embodiment of the present disclosure, the first millimeter wave transceiver array and the second millimeter wave transceiver array are arranged in the same direction and are each arranged along one of a straight line, an arc line and a fold line.
In an exemplary embodiment of the present disclosure, the at least one first reflecting plate is fixed above and/or below the first millimeter wave transceiving array; and/or the at least one second reflecting plate is fixed below and/or above the second millimeter wave transceiver array.
In an exemplary embodiment of the present disclosure, the number of the first reflection plates is two, and the two first reflection plates are respectively fixed at two ends of the first millimeter wave transceiver array along the arrangement direction; and/or the number of the second reflecting plates is two, and the two second reflecting plates are respectively fixed at two ends of the second millimeter wave receiving and transmitting array along the arrangement direction.
In an exemplary embodiment of the present disclosure, the number of the first reflection plates is four, and the four first reflection plates are respectively fixed at two ends of the first millimeter wave transceiver array along the arrangement direction, wherein two first reflection plates are fixed above the first millimeter wave transceiver array, and the other two first reflection plates are fixed below the first millimeter wave transceiver array; and/or the number of the second reflecting plates is four, the four second reflecting plates are respectively fixed at two ends of the second millimeter wave receiving and transmitting array along the arrangement direction, wherein two second reflecting plates are fixed above the second millimeter wave receiving and transmitting array, and the other two second reflecting plates are fixed below the second millimeter wave receiving and transmitting array.
In an exemplary embodiment of the present disclosure, a dimension of the first reflection plate in a first direction perpendicular to the arrangement direction is substantially equal to a dimension of the second millimeter wave transceiver array in the first direction perpendicular to the arrangement direction; and/or the dimension of the second reflecting plate along the first direction perpendicular to the arrangement direction is approximately equal to the dimension of the first millimeter wave transceiver array along the first direction perpendicular to the arrangement direction.
In an exemplary embodiment of the present disclosure, a dimension of the first reflection plate in a second direction perpendicular to the first direction is smaller than half a dimension of the second millimeter wave transceiving array in the arrangement direction; and/or, the dimension of the second reflecting plate along the second direction perpendicular to the first direction is smaller than half of the dimension of the first millimeter wave transceiver array along the arrangement direction.
In an exemplary embodiment of the present disclosure, the first millimeter wave transceiver array and the second millimeter wave transceiver array move synchronously in a vertical direction.
In an exemplary embodiment of the present disclosure, the first millimeter wave transceiver array and the second millimeter wave transceiver array move synchronously in a horizontal direction.
In an exemplary embodiment of the present disclosure, the first millimeter wave transceiver array and the second millimeter wave transceiver array move synchronously along an arc track.
In an exemplary embodiment of the present disclosure, the at least one first reflection plate is disposed at a side of the first millimeter wave transceiving array remote from the detection channel, and extends in a direction perpendicular to an arrangement direction of the first millimeter wave transceiving array and beyond the first millimeter wave transceiving array; and/or the at least one second reflecting plate is arranged on one side, far away from the detection channel, of the second millimeter wave receiving and transmitting array, and extends in a direction perpendicular to the arrangement direction of the second millimeter wave receiving and transmitting array and extends beyond the second millimeter wave receiving and transmitting array.
In an exemplary embodiment of the present disclosure, a dimension of the at least one first reflection plate in a first direction perpendicular to the arrangement direction is substantially equal to a dimension of the millimeter wave imaging device in the first direction perpendicular to the arrangement direction; and/or a dimension of the at least one second reflecting plate in a first direction perpendicular to the arrangement direction is substantially equal to a dimension of the millimeter wave imaging device in the first direction perpendicular to the arrangement direction.
In an exemplary embodiment of the present disclosure, a dimension of the at least one first reflection plate in a second direction perpendicular to the first direction is less than half a dimension of the second millimeter wave transceiving array in the arrangement direction; and/or, the dimension of the at least one second reflecting plate along the second direction perpendicular to the first direction is smaller than half of the dimension of the first millimeter wave transceiver array along the arrangement direction.
In an exemplary embodiment of the present disclosure, the other article has a property of absorbing millimeter waves or being weak to millimeter wave reflection, or the limited range of directions of millimeter waves reflected by the other article causes millimeter waves reflected back thereof to be not received by the millimeter wave transceiving array, and at least part of the other article is located outside the inspected object in the three-dimensional image of the inspected object.
According to an aspect of the present disclosure, there is provided a security inspection apparatus including:
a millimeter wave imaging device as hereinbefore described.
According to another aspect of the present disclosure, there is provided a security inspection method, including:
irradiating an inspected object in the inspection channel with millimeter waves using the millimeter wave imaging apparatus as described above, receiving the millimeter waves reflected back by a subject of the inspected object, and reproducing a three-dimensional image of the subject of the inspected object based on the constructed holographic image of the subject; and constructing a hologram image of a side portion of an inspected object by receiving the millimeter wave reflected from the reflection plate by the millimeter wave imaging device, and reproducing a three-dimensional image of the side portion of the inspected object based on the constructed hologram image of the side portion, thereby determining whether the inspected object contains other articles.
It should be understood that the description in this section is not intended to identify key or critical features of the embodiments of the disclosure, nor is it intended to be used to limit the scope of the disclosure. Other features of the present disclosure will become apparent from the following specification.
Drawings
The accompanying drawings are included to provide a better understanding of the present disclosure, and are not to be construed as limiting the disclosure, wherein:
FIG. 1 shows an apparatus for explaining millimeter wave holographic measurement principles;
FIG. 2 shows a schematic plan scan millimeter wave holographic imaging;
FIG. 3 shows a schematic diagram of a suspected item in accordance with the present disclosure;
fig. 4 shows a schematic diagram of a millimeter wave imaging device according to an embodiment of the present disclosure;
fig. 5 shows an operational schematic diagram of a millimeter wave transceiver array and a reflecting plate of a millimeter wave imaging device according to an embodiment of the present disclosure;
fig. 6 (a) to 6 (e) show schematic diagrams of relative positions of a millimeter wave transceiver array and a reflecting plate of a millimeter wave imaging device according to an embodiment of the present disclosure.
Fig. 7 (a) to 7 (d) show operation modes of the millimeter wave imaging device according to the embodiment of the present disclosure.
Detailed Description
For a clearer description of the objects, technical solutions and advantages of the present disclosure, embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It is to be understood that the following description of the embodiments is intended to illustrate and explain the general concepts of the disclosure and should not be taken as limiting the disclosure. In the description and drawings, the same or similar reference numerals refer to the same or similar parts or components. For purposes of clarity, the drawings are not necessarily drawn to scale and some well-known components and structures may be omitted from the drawings.
Unless defined otherwise, technical or scientific terms used in this disclosure should be given the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The terms "first," "second," and the like, as used in this disclosure, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The terms "a" or "an" do not exclude a plurality. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", "top" or "bottom" and the like are used only to indicate a relative positional relationship, which may be changed accordingly when the absolute position of the object to be described is changed. When an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, it can be "directly on" or "under" the other element or intervening elements may be present.
The millimeter wave electromagnetic radiation has the wavelength range of 1-10 mm and the corresponding frequency range of 30-300 GHz, and has wide application in radar, remote sensing, communication, sensing, nondestructive detection and other aspects. Many materials that are opaque in the optical frequency range are nearly transparent to millimeter waves, so millimeter wave imaging has natural advantages in many cases, and is suitable for non-contact, non-invasive security inspection.
The millimeter wave has the wavelength of millimeter magnitude, has no ionization characteristic compared with X-rays, and is difficult to penetrate the skin surface of a human body, so that the low-power millimeter wave signal is harmless to the human body. Meanwhile, millimeter wave can realize high-resolution imaging of half wavelength, and can distinguish objects with the wavelength of 0.5-5 mm for millimeter waves with the wavelength of 1-10 mm, so that inspection of contraband such as guns, cutters, explosives, even lighters, small bags of drugs and the like in human body security inspection is met.
The millimeter wave has strong penetrability to common clothes, when the frequency is less than 300GHz, the penetrability of the millimeter wave to the clothes is more than-3 dB, and decreases along with the increase of the frequency, and when the frequency is close to the mid-infrared, the penetrability decreases to a level close to-30 dB.
The reflectivity of the skin of the human body to the millimeter wave is close to the metal level, so that the signal to noise ratio of the millimeter wave signal reflected by the surface of the human body is relatively high, and the contours of low-brightness powder suspicious objects and various other suspicious objects can be highlighted under the highlight human body background.
Millimeter wave imaging can be classified into active millimeter wave imaging and passive millimeter wave imaging, the passive millimeter wave imaging does not emit millimeter waves, and only uses a receiving antenna to receive millimeter waves emitted by an object to be inspected, such as a human body, so that the millimeter wave imaging has the advantages of completely not irradiating the human body and having high imaging speed, but is relatively greatly influenced by environment; active millimeter wave imaging is to irradiate an object such as a human body with millimeter waves transmitted by a transmitting antenna, and to receive the returned millimeter waves by a receiving antenna, so that the cost is relatively high, the acquisition time is relatively long, but the influence of the environment is small, and the image quality is good.
Active millimeter wave imaging can realize holographic imaging, and 'holographic' refers to all information required for reconstructing an object image, including amplitude and phase information, a millimeter wave holographic imaging system is usually in an array form, a lens-free focusing device is adopted, and focusing imaging is realized through a signal processing algorithm. The commonality of active millimeter wave holographic imaging and optical holographic imaging is that three-dimensional images are obtained by recording amplitude phase information of waves, and the difference is that millimeter wave holograms directly demodulate and record amplitude phase information, optical holograms have higher difficulty in directly demodulating and recording phase information due to higher optical frequency bands, and usually adopt an indirect mode to record phase information; optical holographic imaging generally includes a recording process and a reproducing process: in the recording process, reference light is introduced to cause the reference light to interfere with object light waves on a holographic interference plate to form interference fringes, and the object light wave front information is recorded: during the reconstruction process, the holographic interference plate is irradiated with the reference light, and the object light wave is reconstructed, so that a stereoscopic image of the object can be seen.
Unlike optical holographic imaging, millimeter wave holographic imaging relies on heterodyne mixing techniques, which measure complex signals that are no longer millimeter wave intensity, but contain amplitude and phase information. The millimeter wave holographic measurement principle is shown in fig. 1, millimeter wave signals sent by a millimeter wave source are divided into two paths through a coupler, one path of signals are irradiated on an imaging object through a transmitting antenna, and the other path of signals are input into an I/Q demodulator to be used as reference signals. The millimeter wave signal reflected by the object is received by the receiving antenna, passes through the power amplifier and is input to the I/Q demodulator as a measurement signal. The I/Q demodulator uses the reference signal to perform phase extraction of the measurement signal.
Under the condition of not considering the signal amplitude, let the millimeter wave signal sent by the millimeter wave source be cos omega t, omega be the angular frequency of the millimeter wave signal, t beTime. The millimeter wave signal received by the receiving antenna introduces the phase to be measured due to the process of incidence to the surface of the object and reflectionThe signal can then be expressed as +.>The mixer mainly comprises a multiplier and a band-pass filter. The product of the two signals input to mixer 1 is:
the mixer 1 performs low-pass filtering on the signal to obtain the real part I of the complex signal to be detected. The reference signal input to the mixer 2 is first subjected to 90-degree phase shift, and is obtained after being subjected to multiplier:
Similarly, the imaginary part Q of the complex signal to be measured can be obtained by low-pass filtering the above signal. In actual measurement, the output signal of the I/Q demodulator also contains amplitude information:
in the above, A is the amplitude of the complex signal to be measured,is the phase of the complex signal to be measured.
The millimeter wave holographic imaging can directly extract phase information by utilizing the measuring circuit, so that the irradiation of reference waves is not needed, the imaging device is greatly simplified, and the imaging of any field of view is conveniently finished.
In one embodiment of the present disclosure, referring to fig. 2, the transmit-receive antennas RX and TX of the millimeter wave direct-hologram imaging system are disposed adjacent, approximately at the same location. The transmitting antenna TX emits spherical waves exp (-jkr)/r (r is the distance) to irradiate the imaged object, each point on the object scatters the millimeter wave signal, and the scattered signal received by the receiving antenna will be a superposition of the scattered signals at various positions on the surface of the object. Under the assumption of Born primary scattering approximation and isotropic scattering, the millimeter wave signal received by the receiving antenna can be expressed as:
wherein, (x) 0 ,y 0 ) For transceiving the position of the antenna, f (x, y) is the complex reflectivity image of the object at the (x, y) position, For the distance between a point on the object and the transmit-receive antenna (assuming the imaged object is two-dimensional, the distance between the object and the scan aperture is Z 0 ). S (x) 0 ,y 0 ) The complex signal obtained by heterodyne mixing technology measurement is scanned to obtain a hologram to be measured, and then the complex reflectivity image f (x, y) of the object is obtained by inversion of an image reconstruction algorithm.
According to the present disclosure, in an actual security inspection process, a missed inspection may occur, for example, as shown in fig. 3, a human body carries a foreign object (located on a side of the human body), and the foreign object may generate shadows like the human body under irradiation of visible light, resulting in shadows as shown in fig. 3, and thus may be observed. However, in the case of holographic imaging, the transmitting antenna transmits millimeter waves toward the human body, the human body reflects the millimeter waves strongly, so that the human body appears bright on the image, the space (background) outside the human body appears black on the image, if the foreign matter carried by the human body has strong absorptivity to the millimeter waves, the millimeter waves are absorbed, reflected on the image as black, and the same color as the image of the (space) background, so that the contrast of the foreign matter portion in the resulting image is weak (or the image with the foreign matter is not seen), if such foreign matter is distinguishable within the human body imaging area, but if the foreign matter is outside or near the human body, for example, the foreign matter is in the position shown in fig. 3, both the foreign matter and the background appear black on the image, it is not easily distinguishable, and thus a missed detection situation may be caused.
According to an embodiment of the present disclosure, there is provided a millimeter wave holographic imaging device including millimeter wave transceiver arrays 1, 2 for transmitting millimeter waves and receiving reflected millimeter waves; and reflection plates 11, 12, 21, 22 arranged to oppose the millimeter wave transceiving arrays 1, 2 so that a part of millimeter waves emitted from the millimeter wave transceiving arrays 1, 2 can be reflected to a side of the inspected object, and the reflected signals can be reflected back to the reflection plates 11, 12, 21, 22 via the side of the inspected object, and then the reflection plates 11, 12, 21, 22 can reflect millimeter waves reflected back to the side of the inspected object to the millimeter wave transceiving arrays 1, 2.
In an embodiment, the millimeter wave transceiver array 1, 2 has at least one row of transmitting antennas TX and receiving antennas RX, for example, each transmitting antenna TX and one receiving antenna RX may be adjacently arranged, and may form a pair of transmitting antennas TX-receiving antennas RX, and the pairs of transmitting antennas TX-receiving antennas RX are arranged in one dimension. The millimeter wave transceiver array may include one row of transmit antenna TX-receive antenna RX pairs or may include two or more rows of transmit antenna TX-receive antenna RX pairs. In one embodiment, each pair of transmit antennas TX-receive antennas RX may be arranged along a millimeter wave transceiver array, such as in a horizontal direction; in another embodiment, each pair of transmitting antennas TX-receiving antennas RX may be arranged in a lateral direction of the millimeter wave transceiver array, for example, up and down, in which case all transmitting antennas TX form a row and all receiving antennas RX form a row; in other embodiments, each pair of transmit antennas TX-receive antennas RX may be arranged in other directions.
A pair of transceiver antennas is referred to as a lane, and for an array, a transceiver array includes a set of transceiver antenna pairs, e.g., n pairs of transceiver antennas, i.e., n lanes; in performing the examination, the transmission and reception of signals from the first pair of transceiver antennas is started, for example for several milliseconds, and then the transmission and reception of signals from the second pair of transceiver antennas is started for several milliseconds, and the n pairs of transceiver antennas are operated in sequence, completing a scan of the transceiver antenna array, wherein the transmission signal is of a fixed frequency (so-called fixed frequency scan). The transceiver antenna array may perform a second scan, operating similarly to the first scan, but transmitting a signal at another fixed frequency. The transceiver antenna array may perform multiple scans of a set of frequencies.
In one embodiment, the millimeter wave transceiver array is disposed opposite the reflector plate and defines an inspection channel. The object to be inspected (e.g., human body, other inspected object, etc.) stays on the inspection channel to complete the inspection. Specifically, a main body (for example, a front surface, a back surface and other areas of a human body) of an inspected object positioned on the inspection channel reflects millimeter waves emitted by the millimeter wave receiving and transmitting array back to the millimeter wave receiving and transmitting array; meanwhile, the reflecting plate reflects part of the millimeter waves emitted by the millimeter wave receiving and transmitting array to the side part of the checked object (such as the waist, leg side, neck side and other areas of the human body), the signals reflected by the reflecting plate can be reflected back to the reflecting plate through the side part of the checked object, and then the reflecting plate can reflect the millimeter waves reflected back by the side part of the checked object to the millimeter wave receiving and transmitting array. The millimetric wave imaging device is capable of constructing a holographic image of a subject of an object under inspection (for example, the front and back of a human body) based on received millimetric waves reflected back from the surface of the object under inspection, and reproducing a three-dimensional image of the subject of the object under inspection based on the constructed holographic image of the subject. The millimetric wave imaging device is also capable of obtaining mirror images at the mirror image areas 41, 42 based on the millimetric wave reflected from, for example, the reflection plates 21, 22 to construct a holographic image of the side portion of the object to be inspected, and reproducing a three-dimensional image of the side portion of the object to be inspected based on the constructed holographic image of the side portion, as shown in fig. 5. Through providing first millimeter wave transceiver array 1 and second millimeter wave transceiver array 2, can be through the holographic image reconstruction surface image of the main part of inspection object, combine first reflecting plate 11, 12 and second reflecting plate 21, 22 to rebuild out the invisible image in former weak region in the position of respective symmetry to effectively solve millimeter wave signal and cover the poor imaging effect or the imaging blind area problem that causes of effect, and then improved the detection accuracy, avoided the omission and greatly reduced imaging complexity.
For example, there is a suspected article on the side of the human body, as shown in fig. 3, the millimeter wave emitted by the millimeter wave receiving and transmitting array irradiates the human body, the millimeter wave is reflected back to the millimeter wave receiving and transmitting array by the human body, and the millimeter wave is not directly reflected back to the millimeter wave receiving and transmitting array because the suspected article absorbs the millimeter wave. The millimetric wave imaging device constructs a holographic image of a subject of a human body (for example, the front and back sides of the human body) based on the received millimetric wave reflected from the human body, and reproduces a three-dimensional image of the subject of the human body based on the constructed holographic image of the subject, and since the suspected object is reflected on the image in black as the image of the (spatial) background, the suspected object is not obvious in the three-dimensional image of the subject of the human body. According to the embodiment, the reflection plate reflects the millimeter waves emitted by the millimeter wave receiving and transmitting array to the human body side, the human body side reflects the millimeter waves, and the reflected millimeter waves are reflected back to the millimeter wave receiving and transmitting array through the reflection plate. The millimeter wave imaging apparatus constructs a holographic image of a side portion of a human body based on the millimeter waves reflected from the reflection plate, and reproduces a three-dimensional image of the side portion of the human body based on the constructed holographic image of the side portion of the human body, since the human body appears bright on the image, and the suspected article is reflected in the image as black, and the suspected article is in the middle of the side portion of the human body in the three-dimensional image of the side portion of the human body, the suspected article is more obvious.
In one embodiment, the reflecting plate forms an included angle of 0 to 90 degrees with the millimeter wave receiving and transmitting array, so that the side part of the inspected object can receive the millimeter wave signal sent by the millimeter wave receiving and transmitting array and reflected by the reflecting plate, and meanwhile, the reflected signal in the area can be reflected back to the receiving antenna of the millimeter wave receiving and transmitting array through the reflecting plate, thereby receiving and collecting the millimeter wave signal.
In one embodiment, as shown in fig. 4, the millimeter wave transceiver array includes a first millimeter wave transceiver array 1 located on a first side of the inspection tunnel and a second millimeter wave transceiver array 2 located on a second side of the inspection tunnel opposite the first side. The reflection plates include at least one first reflection plate 11, 12 arranged corresponding to the second millimeter wave transceiving array 2 and at least one second reflection plate 21, 22 arranged corresponding to the first millimeter wave transceiving array 1. The first reflecting plates 11, 12 form an angle of 0 to 90 degrees with the second millimeter wave transceiver array 2, so that the first reflecting plates 11, 12 can reflect part of millimeter waves emitted by the second millimeter wave transceiver array 2 to the side of the inspected object and can reflect millimeter waves reflected by the side of the inspected object back to the second millimeter wave transceiver array 2, and the second millimeter wave transceiver array 2 can receive millimeter waves reflected back by the first reflecting plates 11, 12. The second reflection plates 21, 22 form an angle of 0 to 90 degrees with the first millimeter wave transceiver array 1, so that the second reflection plates 21, 22 can reflect part of the millimeter waves emitted from the first millimeter wave transceiver array 1 to the side of the inspected object and can reflect the millimeter waves reflected from the side of the inspected object back to the first millimeter wave transceiver array 1, and the first millimeter wave transceiver array 1 can receive the millimeter waves reflected back by the second reflection plates 21, 22.
In the embodiment of the present disclosure, as shown in fig. 4, the arrangement directions X of the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 are the same, and are all arranged in the horizontal direction, that is, the pairs of the plurality of transmitting antennas TX and the receiving antennas RX of the first millimeter wave transceiver array 1 are arranged in the horizontal direction, and the pairs of the plurality of transmitting antennas TX and the receiving antennas RX of the second millimeter wave transceiver array 2 are also arranged in the horizontal direction. In the present embodiment, as shown in fig. 7 (a), the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 arranged in the horizontal direction are moved synchronously in the vertical direction, that is, simultaneously in the same direction at the same speed from top to bottom or from bottom to top, respectively. The first vertical slide rail assembly 31 and the second vertical slide rail assembly 32 may be provided, and the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 are respectively supported by the first vertical slide rail assembly 31 and the second vertical slide rail assembly 32 and respectively move synchronously along the vertical direction through the first vertical slide rail assembly 31 and the second vertical slide rail assembly 32, so as to realize vertical scanning of the inspected object.
In the embodiment of the present disclosure, as shown in fig. 4, the at least one first reflecting plate 11, 12 is fixed above the first millimeter wave transceiver array 1, and the at least one second reflecting plate 21, 22 is fixed below the second millimeter wave transceiver array 2. It should be noted that, in other embodiments of the present disclosure, as shown in fig. 6 (b), the at least one second reflecting plate 21, 22 may also be fixed above the second millimeter wave transceiver array 2; alternatively, as shown in fig. 6 (c), two first reflection plates 11, 12 may be fixed below the first millimeter wave transmission/reception array 1; or as shown in fig. 6 (d), the first reflection plates 11a, 11b, 12a, 12b are provided above and below the first millimeter wave transmitting-receiving array 1, and the second reflection plates 21a, 21b, 22a, 22b are provided above and below the second millimeter wave transmitting-receiving array 2. By disposing the reflective plate above and/or below the millimeter wave transceiver array, the footprint of the device may be substantially reduced.
In the embodiment of the present disclosure, as shown in fig. 4, the number of the first reflection plates 11, 12 is two, and the two first reflection plates 11, 12 are respectively fixed at two ends of the first millimeter wave transceiver array 1 along the arrangement direction X, so as to respectively realize scanning of opposite sides of the inspected object. The number of the second reflecting plates 21, 22 may be two, and the two second reflecting plates 21, 22 are respectively fixed at two ends of the second millimeter wave transceiver array 2 along the arrangement direction X. To respectively effect scanning of opposite sides of the inspected object.
Fig. 6 (d) shows an embodiment of a millimeter wave imaging device according to the present disclosure, unlike the embodiment shown in fig. 4, the number of first reflection plates is four, four first reflection plates are fixed to both ends of the first millimeter wave transceiver array 1 in the arrangement direction X, respectively, wherein two first reflection plates 11a, 12a are fixed above the first millimeter wave transceiver array 1, and the other two first reflection plates 11b, 12b are fixed below the first millimeter wave transceiver array 1. The number of the second reflecting plates may be four, and the four second reflecting plates are respectively fixed at two ends of the second millimeter wave transceiver array 2 along the arrangement direction X, where two second reflecting plates 21a and 22a are fixed above the second millimeter wave transceiver array 2, and the other two second reflecting plates 21b and 22b are fixed below the second millimeter wave transceiver array 2.
In the embodiment shown in fig. 6 (a) to 6 (d), in order to ensure that the first reflection plates 11, 12 can cover the inspected object in the first direction Y (i.e., the vertical direction in the drawing) and the size is as small as possible, the size of the first reflection plates 11, 12 in the first direction Y perpendicular to the arrangement direction X is substantially equal to the size of the second millimeter wave transceiver array 2 in the first direction Y perpendicular to the arrangement direction X, for the purpose of reducing the cost. Likewise, the dimension of the second reflection plates 21, 22 in the first direction Y perpendicular to the arrangement direction X is substantially equal to the dimension of the first millimeter wave transceiver array 1 in the first direction Y perpendicular to the arrangement direction X. In order to ensure that the first reflection plates 11, 12 can cover the inspected object in the second direction (i.e., the horizontal direction in the drawing) perpendicular to the first direction Y, and the size is as small as possible, in order to reduce the cost, the size of the first reflection plates 11, 12 in the second direction perpendicular to the first direction Y is smaller than half the size of the second millimeter wave transceiver array 2 in the arrangement direction X; and/or the second reflection plates 21, 22 have a dimension in the second direction perpendicular to the first direction Y that is smaller than half of the dimension of the first millimeter wave transceiver array 1 in the arrangement direction X.
Fig. 6 (e) shows an embodiment of a millimeter wave imaging device according to the present invention, unlike the embodiment shown in fig. 6 (a), the at least one first reflection plate 11, 12 is provided on a side of the first millimeter wave transceiver array 1 remote from the detection channel, and extends in a direction perpendicular to the arrangement direction X of the first millimeter wave transceiver array 1 and beyond the first millimeter wave transceiver array 1. The at least one second reflecting plate 21, 22 may be disposed at a side of the second millimeter wave transceiver array 2 remote from the detection channel, and extend in a direction perpendicular to the arrangement direction X of the second millimeter wave transceiver array 2 and beyond the second millimeter wave transceiver array 2. In the embodiment shown in fig. 6 (e), neither the first reflection plates 11, 12 nor the second reflection plates 21, 22 move with the array, and thus the first reflection plates 11, 12 and the second reflection plates 21, 22 are large in size to ensure that the inspected object can be covered in the first direction Y perpendicular to the arrangement direction X. Preferably, the dimension of the at least one first reflecting plate 11, 12 in the first direction Y perpendicular to the arrangement direction X is substantially equal to the dimension of the millimeter wave imaging device in the first direction Y perpendicular to the arrangement direction X to ensure coverage of the inspected object in the first direction Y perpendicular to the arrangement direction X (i.e., the vertical direction in the drawing). The dimension of the at least one second reflection plate 21, 22 in the first direction Y perpendicular to the arrangement direction X is substantially equal to the dimension of the millimeter wave imaging device in the first direction Y perpendicular to the arrangement direction X to ensure coverage of the inspected object in the first direction Y perpendicular to the arrangement direction X (i.e., the vertical direction in the drawing). The dimension of the at least one first reflecting plate 11, 12 in the second direction perpendicular to the first direction Y is smaller than half the dimension of the second millimeter wave transceiver array in the arrangement direction X to ensure coverage of the inspected object in the second direction perpendicular to the first direction Y (i.e., the horizontal direction in the drawing). The dimension of the at least one second reflecting plate 21, 22 in the second direction perpendicular to the first direction Y is smaller than half the dimension of the first millimeter wave transceiver array in the arrangement direction X to ensure coverage of the inspected object in the second direction perpendicular to the first direction Y (i.e., the horizontal direction in the drawing).
In one embodiment of the present disclosure, the millimeter wave imaging device may include a driving device for driving the slider of the first vertical sliding rail assembly 31 to move up and down with respect to the sliding rail of the first vertical sliding rail assembly 31, so as to drive the first millimeter wave transceiver array 1 connected to the slider to move up and down. The driving device can also drive the sliding block of the second vertical sliding rail assembly 32 to move up and down relative to the sliding rail of the second vertical sliding rail assembly 32, so as to drive the second millimeter wave transceiver array 2 connected with the sliding block to move up and down. The drive may be, for example, a servo drive.
As shown in fig. 4, the millimeter wave imaging device may further include a docking station 4, and the first and second vertical slide assemblies 31 and 32 may be supported on the docking station 4. At the time of examination, a person can stand on the platform 4 to receive the examination.
According to the embodiment of the present disclosure, the first reflection plates 11, 12 and the second reflection plates 21, 22 may be similar reflection plates, however, they do not need to be identical.
The first reflecting plates 11, 12 and the second reflecting plates 21, 22 are made of metal, for example: aluminum, iron, copper, alloys thereof, etc., or a nonmetallic substrate is coated with a metal film.
Fig. 7 (b) shows an embodiment of a millimeter wave imaging device according to the present disclosure, unlike the embodiment shown in fig. 7 (a), the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 are arranged in the vertical direction. In the present embodiment, the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 arranged in the vertical direction are moved synchronously in the horizontal direction (as indicated by the arrow in the figure), respectively, for example, simultaneously in the same direction at the same speed. Fig. 7 does not show a slide rail assembly for supporting and moving the first and second millimeter wave transceiver arrays 1 and 2, respectively, but it should be understood that, similarly to the embodiment of fig. 4, a first and second horizontal slide rail assembly may be provided so as to allow the first and second millimeter wave transceiver arrays 1 and 2 to move in the horizontal direction to achieve horizontal scanning of an object to be inspected. The imaging principle of the millimeter wave imaging device of the present embodiment is the same as that of the millimeter wave imaging device shown in fig. 4, and the description thereof will not be repeated here.
Fig. 7 (c) shows an embodiment of a millimeter wave imaging device according to the present disclosure, unlike the embodiment shown in fig. 7 (b), the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 arranged in the vertical direction move along an arc-shaped track or line (as indicated by an arrow in the figure). For example, a first horizontal slide rail assembly and a second horizontal slide rail assembly having arc-shaped rails are provided so as to allow the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 to move along the arc-shaped rails to achieve cylindrical scanning of the inspected object. In the present embodiment, the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 move synchronously along the curved track, for example, scan at the same speed in the same direction at the same time.
Fig. 7 (d) shows an embodiment of a millimeter wave imaging device according to the present invention, unlike the embodiment shown in fig. 7 (a), the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 have an arc shape, in other words, a plurality of pairs of transmitting antennas TX and receiving antennas RX of the first millimeter wave transceiver array 1 are arranged along an arc shape, for example, along an arc shape in a horizontal plane. The first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 which are arranged in an arc shape define an inspection channel, and the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 which are arranged in an arc shape encircle a human body or other detected objects. Similar to the millimeter wave imaging apparatus shown in fig. 4, the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2, which are arranged in an arc shape in a horizontal plane, may be moved up and down synchronously on the first vertical slide rail assembly and the second vertical slide rail assembly, respectively, for example, simultaneously scanned in the same direction at the same speed, so as to realize cylindrical scanning of the inspected object. The embodiment of fig. 7 (d) achieves the surrounding of the human body or the object to be inspected with the millimeter wave transceiver array, and thus the human body or the object to be inspected can be irradiated from more angles than in fig. 7 (a), enabling more reliable inspection. For example, when a person carries a suspected object, if the array and the reflective plate are in the form of fig. 7 (a), and millimeter waves reflected from the front surface, the back surface and the reflective plate cannot be irradiated to the suspected object, the suspected object cannot be distinguished from the main body images of the front surface and the back surface of the array and the body-side mirror image corresponding to the reflective plate; however, since the millimeter wave transceiver array of fig. 7 (d) is capable of illuminating the human body from more angles, the millimeter waves emitted from the transceiver array or reflected by the reflecting plate can illuminate the suspected object at these angles, and the suspected object can be distinguished from the body image or the image of the body side mirror image corresponding to the reflecting plate at this time. Through a proper algorithm, the suspected articles are resolved, and the accuracy and the reliability of the equipment are greatly improved.
It should be noted that, in other embodiments of the present disclosure, the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 may also have a shape of a broken line, in other words, the pairs of the transmitting antennas TX and the receiving antennas RX of the first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 are arranged along the broken line. Here, a polyline is meant to include a multi-segment line segment, where the multi-segment line segments are connected to each other at an angle. The first millimeter wave transceiver array 1 and the second millimeter wave transceiver array 2 which are arranged in a zigzag shape encircle a human body or other detected objects. In addition, the scanning mode of the millimeter wave imaging device is not limited to the plane scanning and the cylindrical scanning disclosed herein, and a scanning mode of linear array and mechanical scanning and full-electronic scanning can be adopted.
An aspect of the present disclosure also provides a security inspection apparatus including the millimeter wave imaging apparatus described above.
The millimeter wave imaging device may also include other auxiliary devices.
An aspect of the present disclosure also provides a security inspection method, including: irradiating an inspected object in the inspection channel with millimeter waves using the above millimeter wave imaging apparatus, receiving the millimeter waves reflected back by a subject of the inspected object, and reproducing a three-dimensional image of the subject of the inspected object based on the constructed holographic image of the subject; and constructing a hologram image of a side portion of an inspected object by receiving the millimeter wave reflected from the reflection plate by the millimeter wave imaging device, and reproducing a three-dimensional image of the side portion of the inspected object based on the constructed hologram image of the side portion, thereby determining whether the inspected object contains other articles.
It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps recited in the present disclosure may be performed in parallel, sequentially, or in a different order, provided that the desired results of the disclosed aspects are achieved, and are not limited herein.
The above detailed description should not be taken as limiting the scope of the present disclosure. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives to the disclosed embodiments or examples can be made depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present disclosure are intended to be included within the scope of the present disclosure.
Claims (18)
1. A millimeter wave imaging device, comprising:
the millimeter wave receiving and transmitting array is used for transmitting millimeter waves and receiving the reflected millimeter waves; and
a reflection plate configured to be opposed to the millimeter wave transceiving array so as to be capable of reflecting a portion of millimeter waves emitted by the millimeter wave transceiving array to a side portion of an inspected object, and a reflected signal being capable of being reflected back to the reflection plate via the side portion of the inspected object, the reflection plate being capable of reflecting millimeter waves reflected back by the side portion of the inspected object to the millimeter wave transceiving array;
The millimeter wave receiving and transmitting array and the reflecting plate define an inspection channel, and the surface of an inspected object positioned on the inspection channel reflects millimeter waves emitted by the millimeter wave receiving and transmitting array back to the millimeter wave receiving and transmitting array;
wherein the millimetric wave imaging device is capable of constructing a holographic image of a subject of the inspected object based on the received millimetric wave reflected back from the surface of the inspected object and reproducing a three-dimensional image of the subject of the inspected object based on the constructed holographic image of the subject; and the millimetric wave imaging device is further capable of constructing a holographic image of a side portion of the inspected object based on the millimetric wave reflected from the reflection plate and reproducing a three-dimensional image of the side portion of the inspected object based on the constructed holographic image of the side portion, thereby determining whether the inspected object contains other articles.
2. The millimeter wave imaging device of claim 1, wherein the reflecting plate forms an angle of 0 to 90 degrees with the millimeter wave transceiver array.
3. The millimeter wave imaging device of claim 2, wherein the millimeter wave transceiver array comprises a first millimeter wave transceiver array located on a first side of the inspection tunnel and a second millimeter wave transceiver array located on a second side of the inspection tunnel opposite the first side, the reflective plate comprising at least one first reflective plate disposed in correspondence with the second millimeter wave transceiver array and at least one second reflective plate disposed in correspondence with the first millimeter wave transceiver array; the at least one first reflecting plate can reflect part of millimeter waves emitted by the second millimeter wave receiving and transmitting array to the side part of the inspected object, and can reflect millimeter waves reflected by the side part of the inspected object back to the second millimeter wave receiving and transmitting array; the at least one second reflecting plate can reflect a part of the millimeter waves emitted by the first millimeter wave transmitting-receiving array to the side part of the inspected object, and can reflect the millimeter waves reflected by the side part of the inspected object back to the first millimeter wave transmitting-receiving array.
4. The millimeter wave imaging device of claim 3, wherein the first millimeter wave transceiver array and the second millimeter wave transceiver array are arranged in the same direction and are each arranged along one of a straight line, an arc line, and a fold line.
5. The millimeter wave imaging device of claim 4, wherein the at least one first reflective plate is fixedly disposed above and/or below the first millimeter wave transceiver array; and/or the at least one second reflecting plate is fixedly arranged below and/or above the second millimeter wave transceiver array.
6. The millimeter wave imaging device according to claim 5, wherein the number of the first reflecting plates is two, and the two first reflecting plates are respectively fixed at both ends of the first millimeter wave transceiver array in the arrangement direction; and/or the number of the second reflecting plates is two, and the two second reflecting plates are respectively fixed at two ends of the second millimeter wave receiving and transmitting array along the arrangement direction.
7. The millimeter wave imaging device according to claim 5, wherein the number of the first reflecting plates is four, the four first reflecting plates are respectively fixed at both ends of the first millimeter wave transceiving array in the arrangement direction, wherein two first reflecting plates are fixed above the first millimeter wave transceiving array, and the other two first reflecting plates are fixed below the first millimeter wave transceiving array; and/or the number of the second reflecting plates is four, the four second reflecting plates are respectively fixed at two ends of the second millimeter wave receiving and transmitting array along the arrangement direction, wherein two second reflecting plates are fixed above the second millimeter wave receiving and transmitting array, and the other two second reflecting plates are fixed below the second millimeter wave receiving and transmitting array.
8. The millimeter wave imaging device according to claim 4, wherein a dimension of the first reflecting plate in a first direction perpendicular to the arrangement direction is substantially equal to a dimension of the second millimeter wave transceiver array in the first direction perpendicular to the arrangement direction; and/or the dimension of the second reflecting plate along the first direction perpendicular to the arrangement direction is approximately equal to the dimension of the first millimeter wave transceiver array along the first direction perpendicular to the arrangement direction.
9. The millimeter wave imaging device according to claim 8, wherein a dimension of the first reflecting plate in a second direction perpendicular to the first direction is smaller than half a dimension of the second millimeter wave transceiving array in the arrangement direction; and/or, the dimension of the second reflecting plate along the second direction perpendicular to the first direction is smaller than half of the dimension of the first millimeter wave transceiver array along the arrangement direction.
10. The millimeter wave imaging device of claim 5, wherein the first millimeter wave transceiver array and the second millimeter wave transceiver array move synchronously in a vertical direction.
11. The millimeter wave imaging device of claim 5, wherein the first millimeter wave transceiver array and the second millimeter wave transceiver array move synchronously in a horizontal direction.
12. The millimeter wave imaging device of claim 5, wherein the first millimeter wave transceiver array and the second millimeter wave transceiver array move in synchronization along an arc trajectory.
13. The millimeter wave imaging device according to claim 4, wherein the at least one first reflecting plate is provided on a side of the first millimeter wave transceiving array remote from the detection channel, and extends in a direction perpendicular to an arrangement direction of the first millimeter wave transceiving array and beyond the first millimeter wave transceiving array; and/or the at least one second reflecting plate is arranged on one side, far away from the detection channel, of the second millimeter wave receiving and transmitting array, and extends in a direction perpendicular to the arrangement direction of the second millimeter wave receiving and transmitting array and extends beyond the second millimeter wave receiving and transmitting array.
14. The millimeter wave imaging device of claim 13, wherein a dimension of the at least one first reflective plate in a first direction perpendicular to the arrangement direction is approximately equal to a dimension of the millimeter wave imaging device in the first direction perpendicular to the arrangement direction; and/or a dimension of the at least one second reflecting plate in a first direction perpendicular to the arrangement direction is substantially equal to a dimension of the millimeter wave imaging device in the first direction perpendicular to the arrangement direction.
15. The millimeter wave imaging device of claim 14, wherein a dimension of the at least one first reflective plate in a second direction perpendicular to the first direction is less than half a dimension of the second millimeter wave transceiver array in the arrangement direction; and/or, the dimension of the at least one second reflecting plate along the second direction perpendicular to the first direction is smaller than half of the dimension of the first millimeter wave transceiver array along the arrangement direction.
16. The millimeter wave imaging device according to any one of claims 1 to 15, wherein the other article has a property of absorbing millimeter waves or being weak in reflection against millimeter waves, or the limited range of directions of millimeter waves reflected by the other article causes millimeter waves reflected back thereof not to be received by a millimeter wave transceiving array, and at least part of the other article is located outside the inspected object in a three-dimensional image of the inspected object.
17. A security inspection apparatus comprising:
a millimetre wave imaging device according to any preceding claim.
18. A security inspection method comprising:
irradiating an inspected object in the inspection channel with millimeter waves using the millimeter wave imaging device of claim 1, receiving the millimeter waves reflected back by a subject of the inspected object, and reproducing a three-dimensional image of the subject of the inspected object based on the constructed holographic image of the subject; and constructing a hologram image of a side portion of an inspected object by receiving the millimeter wave reflected from the reflection plate by the millimeter wave imaging device, and reproducing a three-dimensional image of the side portion of the inspected object based on the constructed hologram image of the side portion, thereby determining whether the inspected object contains other articles.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311808561.XA CN117538948A (en) | 2023-12-26 | 2023-12-26 | Millimeter wave imaging device, security inspection device and security inspection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311808561.XA CN117538948A (en) | 2023-12-26 | 2023-12-26 | Millimeter wave imaging device, security inspection device and security inspection method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117538948A true CN117538948A (en) | 2024-02-09 |
Family
ID=89782531
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311808561.XA Pending CN117538948A (en) | 2023-12-26 | 2023-12-26 | Millimeter wave imaging device, security inspection device and security inspection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117538948A (en) |
-
2023
- 2023-12-26 CN CN202311808561.XA patent/CN117538948A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2017107284A1 (en) | Human body security check system and method based on millimeter wave holographic three-dimensional imaging | |
| US7671784B2 (en) | Computerized tomography using radar | |
| Wang et al. | Review of active millimeter wave imaging techniques for personnel security screening | |
| AU2015227069B2 (en) | Ultra wide band detectors | |
| Sheen et al. | Active millimeter-wave standoff and portal imaging techniques for personnel screening | |
| WO2017107283A1 (en) | Apparatus and method for security check of multiple human bodies based on linear frequency modulation | |
| CN105866771B (en) | A kind of cache detecting system and its detection method | |
| CN108152821A (en) | A kind of active MMW imaging safety detecting system and safety detection method | |
| CN104965233B (en) | Multifrequency Terahertz detection system | |
| US8948847B2 (en) | Millimeter wave 3-D breast imaging | |
| CN114002160B (en) | Terahertz frequency modulation continuous wave nondestructive testing imaging system and method | |
| CN117538948A (en) | Millimeter wave imaging device, security inspection device and security inspection method | |
| CN117572519A (en) | Millimeter wave imaging device, security inspection device and security inspection method | |
| US10641889B2 (en) | Device for detecting objects borne by an individual | |
| Sheen et al. | Advanced millimeter-wave security portal imaging techniques | |
| CN117555038A (en) | Millimeter wave imaging device, security inspection device and security inspection method | |
| CN117538949A (en) | Millimeter wave imaging device, security inspection device and security inspection method | |
| Kahl et al. | Stand-off real-time synthetic imaging at mm-wave frequencies | |
| US20060254358A1 (en) | Apparatus and a method for determining the spatial distribution of physical parameters in an object | |
| RU2522853C1 (en) | Method and apparatus for detecting and identifying objects hidden under clothes on human body | |
| McMakin et al. | Millimeter-wave imaging for concealed weapon detection | |
| Hong et al. | Performance Evaluation of mmWave SAR Imaging Systems using K-domain interpolation and Matched filter methods | |
| Godinho et al. | Feasibility study of focal lens for multistatic microwave breast imaging | |
| CN117741813A (en) | Method for calibrating signal of millimeter wave security inspection instrument, imaging method and storage medium | |
| Ghazi | Modeling and experimental validation for 3D mm-Wave radar imaging |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |