KR100882027B1 - System for visualizing millimeter wave and method of visualizing millimeter wave - Google Patents

Abstract

A millimeter wave visualizing system and method are provided to narrow the beam width of an antenna which receives millimeter wave signals by using a lens antenna so as to form more distinct images. A millimeter wave visualizing system includes a lens antenna(100) for receiving a millimeter wave signal emitted from at least one external object, a driver(140) having a motor for rotating the lens antenna, an image processor(150) for processing the millimeter wave signal received through the lens antenna into a millimeter wave image, and a controller(160) for controlling the driver to rotate the lens antenna according to a predetermined rotation rule and processing the millimeter wave signal into the millimeter wave image through the image processor.

Description

Millimeter wave imaging system and millimeter wave imaging method {System For Visualizing Millimeter Wave And Method Of Visualizing Millimeter Wave}

The present invention relates to a millimeter wave imaging system and a millimeter wave imaging method, and more particularly, to a millimeter wave imaging capable of receiving and imaging a millimeter wave signal radiated from a search target through a lens antenna having an integrated lens and an antenna. System and millimeter wave imaging method.

In general, airports and various conference halls install metal detectors to detect metallic substances such as firearms and prohibit the introduction of dangerous materials. The metal detectors use electromagnetic induction to change the properties depending on the presence or absence of metallic substances. It is used to detect firearms or other metallic dangerous objects.

Metal detectors are portable metal detectors that are carried by security personnel to detect the possession of metals, and gate-type metal detectors that detect metals as they pass through a gate-type structure in turn.

However, in the case of such a metal detector, there is a problem that a desired result cannot be obtained by inaccurate detection by nonmetals or external noise.

In addition, a hidden object detection device for an object used in an airport, such as a safety screening, etc. is typically X-ray detector.

However, in the case of the X-ray detector, there is a concern that the human body in the clothes is clearly expressed, and there is a concern about infringement on the human rights of the individual.

Another type of hidden object sensing device is a sensing device using a millimeter wave, which uses the following principle.

All objects emit a wide band of thermal noise in proportion to their absolute temperature, and a millimeter wave sensing device receives the spectral intensity of the millimeter wave band and forms an image. A millimeter wave is a signal whose wavelength is in millimeters. Since the millimeter wave signal can penetrate clothing, etc., a millimeter wave sensing device can be used to receive a millimeter wave out of thermal noise proportional to the absolute temperature radiated by the human body and belongings inside the garment to form an image. .

In the conventional millimeter wave imaging system, an image sensor scans an image of an object formed through a lens or other method, acquires a signal, and configures it into one image. However, according to such a method, a very precise control is required because the surface of the object must be scanned.

Currently, technology development for a system for receiving a millimeter wave signal and constructing an image has been continuously made, but it is still at an early stage in terms of actual commercialization and commercialization.

The present invention solves the above problems and has been proposed in accordance with recent trends and requests, and by forming a narrower antenna beam width for receiving a millimeter wave signal using a lens antenna composed of a lens and an antenna integrally composed of a clearer image It is an object of the present invention to provide a millimeter wave imaging system and a millimeter wave imaging method.

Another object of the present invention is to provide a millimeter wave imaging system and a millimeter wave imaging method capable of convenient and efficient control by using a lens antenna to reduce the volume of a device and scan a search target itself.

As an aspect of the present invention for achieving the above object, the millimeter wave imaging system according to the present invention, a lens antenna formed integrally with the lens and the antenna for receiving a millimeter wave signal emitted from at least one external object ; A driving unit including a motor for rotating the lens antenna such that a direction in which the lens antenna is directed changes; An image processor configured to form a millimeter wave image of the millimeter wave signal received through the lens antenna; And a controller configured to control the driving unit to rotate the lens antenna according to a predetermined rotation rule, and to configure the millimeter wave signal received at predetermined time intervals according to the rotation of the lens antenna to the millimeter wave image through the image processor. It is done by

In another aspect of the present invention for achieving the above object, the millimeter wave image sensor module according to the present invention, the lens and the antenna integrally formed with a lens for receiving a millimeter wave signal emitted from at least one external object antenna; An amplifier for amplifying and outputting the millimeter wave signal received through the lens antenna; A detector configured to convert the amplified signal into a direct current voltage and output the converted signal; And a driving unit including a motor for rotating the lens antenna so that the direction in which the lens antenna is directed changes.

As another aspect of the present invention for achieving the above object, the millimeter wave imaging method according to the present invention, while rotating the lens antenna formed integrally with the lens and the antenna according to a predetermined rotation rule, Receiving a millimeter wave signal emitted from at least one external object through; And constructing the received millimeter wave signal into a millimeter wave image.

The millimeter wave imaging system and the millimeter wave imaging method according to the present invention described above have the following effects.

First, according to the present invention, since the antenna beam width is narrowed by using a lens antenna having an integrated lens and an antenna, the received millimeter wave signal can be configured into a clearer image.

Second, according to the present invention, the use of a lens antenna has the effect of implementing a millimeter wave imaging system having a smaller volume than the device according to the prior art.

Third, according to the present invention, unlike the prior art in which a very precise control is required by scanning the surface where the image of the object is formed, there is an effect that convenient and efficient control is possible by scanning the search target itself.

The above objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like numbers refer to like elements throughout. In addition, when it is determined that the detailed description of the known function or configuration related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a schematic diagram of a millimeter wave imaging system according to an embodiment of the present invention. 2 is a view showing a state in which the millimeter wave image sensor module according to an embodiment of the present invention is actually implemented. 1 and 2, a millimeter wave imaging system and a millimeter wave image sensor module according to an embodiment of the present invention will be described in detail.

Millimeter wave imaging system according to an embodiment of the present invention, the lens 101 and the antenna 103 is formed integrally with the lens antenna 100, amplifier 110, detector 120, transducer 130, motor The driving unit 140 may include a driving unit 140, a memory 145, an image processing unit 150, a display unit 155, and a controller 160. In addition, the millimeter wave image sensor module according to the exemplary embodiment of the present invention may include the lens antenna 100, the amplifier 110, the detector 120, and the driver 140. In addition, the millimeter wave image sensor module according to an embodiment of the present invention may further include the transducer 130. Hereinafter, the functions of the above components will be described.

The lens antenna 100 receives a millimeter wave signal emitted from at least one external object. 3 is a diagram illustrating an example of a lens antenna. The lens antenna 100 shown in FIG. 3 can receive signals in the 94 GHz band, has a diameter of 3 inches, a gain of about 35 dBi, and a beam width of about 3 degrees. 4 is a diagram illustrating a beam pattern of the lens antenna illustrated in FIG. 3.

The amplifier 110 amplifies the millimeter wave signal received through the lens antenna 100. Since the millimeter wave signal has thermal noise of low signal strength, the amplifier 110 is preferably composed of a high gain and a low noise element. For example, a low noise amplifier (LNA) having a gain of 28 dB with a noise figure of 6 dB may be used in two stages to obtain a performance of greater than 50 dB of super gain. That is, the amplifier 110 may be used by connecting two or more amplifiers having the same or different performances.

The detector 120 converts the millimeter wave signal amplified by the amplifier 110 into a DC voltage. For example, the detector 120 may obtain a DC voltage by rectifying a 94 GHz band signal amplified by the amplifier 110. For example, a 75-110 GHz broadband diode detector having a sensitivity of 500 mV / mW may be used, and the DC output may be configured as an SMA terminal, and may operate without a bias.

The converter 130 converts the DC voltage converted through the detector 120 into a digital signal. The converter 130 is generally referred to as an analog-to-digital converter (ADC).

The driver 140 rotates the lens antenna 100 so that the direction in which the lens antenna 100 is directed by changing the direction of the lens antenna 100 by driving a motor according to the control signal of the controller 150. For example, the driving unit 140 may be implemented as a pan / tilt device capable of rotating up, down, left and right. As an operation example of the pan / tilt device, the pan / tilt device may be moved at intervals of 2.5 ° in a range of 320 ° left and right and 50 ° up and down through RS-232 communication.

The memory 145 stores a predetermined program for controlling the overall operation of the millimeter wave imaging system according to an embodiment of the present invention, and when the overall operation of the millimeter wave imaging system is performed by the controller 160, Stores input / output data and various data processed. In addition, the memory 145 may temporarily or permanently store the digital signal received through the converter 130. In addition, the memory 145 may temporarily or permanently store the millimeter wave image configured by the image processor 150.

The image processor 150 configures a millimeter wave image transmitted through the lens antenna 100, the amplifier 110, the detector 120, and the converter 130 as a millimeter wave image.

The display unit 155 is a display device for displaying the state or various information of the millimeter wave imaging system by the control signal output from the control unit 160.

The controller 160 controls the components and controls the overall operation of the millimeter wave imaging system according to an embodiment of the present invention.

Hereinafter, specific operations of the millimeter wave imaging system and the millimeter wave image sensor module according to an embodiment of the present invention will be described based on the operation of the controller 160.

5 is a diagram for describing an operation of scanning a search range through a lens antenna. The search range means an area to receive a millimeter wave signal. The search range may be set in various ways. For example, the search range 10 shown in FIG. 5 is set as a form of a 5x5 matrix. The size of each component constituting the matrix represents a size of an area in which the lens antenna 100 can receive a millimeter wave signal for a fixed time at a specific position. Also, for example, in FIG. 5, the size of each component constituting the matrix may also be set.

The controller 160 may control the driver 140 to rotate the lens antenna 100 according to a predetermined rotation rule in order to receive a millimeter wave signal for the preset search range.

The rotation rule may relate to at least one of a rotation angle, a rotation direction, and a time fixed at a specific position.

As an example of the rotation angle, in FIG. 5, the lens antenna 100 rotates to scan a specific matrix component and then scans the next matrix component.

6 to 8 are diagrams for explaining the rotation direction of the lens antenna.

For example, FIG. 6 illustrates a scan based on a row and FIG. 7 illustrates a scan based on a coloum. For example, FIG. 8 is a case where each matrix component is scanned clockwise from the matrix components C1 and R1 to the matrix components C3 and R3.

The time fixed at the specific position refers to the time required to receive the millimeter wave signal for each matrix component in FIG. 5.

As such, the controller 160 may control the driver 140 according to the rotation rule to obtain the millimeter wave signal for the entire search range 10.

The controller 160 may control to configure a millimeter wave signal received at predetermined time intervals according to the rotation of the lens antenna 100 to form a millimeter wave image through the image processor 150. In this case, as described above, the millimeter wave signal received through the lens antenna 100 is passed through the amplifier 110, the detector 120, and the converter 130 in the form of a digital signal. Can be delivered.

Hereinafter, the operation of the image processor 150 will be described in detail.

The image processor 150 may configure the received millimeter wave signal as the millimeter wave image by using a voltage difference between the millimeter wave voltage received at the predetermined time interval and a preset reference voltage. In addition, the image processor 150 may include a digital filter. For example, the image processor 150 may obtain a mean value for 50 samples by converting the digital signal transmitted from the converter 130 into a signal of 20 Hz or less through a digital IIR filter configured in three orders. 9A and 9B are graphs showing voltage graphs of millimeter wave signals over time. FIG. 9A is a graph showing a digital signal transmitted from the converter 130 over time, and FIG. 9B is a graph showing a filtering signal through which the digital signal of FIG. 9A has passed through a digital filter. For example, an image having a size of 20 × 20 pixels in which the measured DC voltage value is converted to a gray level using a minimum value-maximum value range of the image configured by the image processor 150. to be.

The time point at which the image processor 150 composes the millimeter wave image may vary. Three examples of the viewpoints of the millimeter wave image will be described.

First, the image processor 150 may configure the millimeter wave image for the entire search range after the reception of the millimeter wave signal for the search range is completed. For example, the millimeter wave signal is received for the entire search range 10 shown in FIG. The millimeter wave signal for the entire search range 10 is stored in the memory 145. The millimeter wave signal for the entire search range 10 stored in the memory 145 may be transmitted to the image processor 150 to form a millimeter wave image.

Second, the image processor 150 may configure the millimeter wave image every time the millimeter wave signal is received at the predetermined time interval. For example, the millimeter wave signal received for each of the matrix components constituting the search range 10 in FIG. 5 may be configured as a millimeter wave image by the image processor 150.

Third, the image processor 150 may configure the millimeter wave signal received for the plurality of matrix components of the search range 10 in FIG. 5 into a millimeter wave image. For example, five matrix components of the search range 50 of FIG. 5 may be scanned, and the scanned five matrix components may be configured as millimeter wave images by the image processor 150. The number of matrix components to be processed at one time by the image processor 150 may be set or changed according to the capacity of the memory 145 and the processing speed of the image processor 150.

The controller 160 may display the millimeter wave image configured by the image processor 150 on the display unit 155.

The image processor 150 may reconstruct the millimeter wave image after configuring the millimeter wave image by using the difference between the voltage of the received millimeter wave signal and the reference voltage. The image reconstruction may vary. For example, the configured millimeter wave image may be reconstructed by enlarging / reducing the size of the image and performing negative image processing.

10 is a diagram illustrating an example of a search range. FIG. 10A illustrates a case in which a special object is not hidden in the body, and FIG. 10B illustrates a case in which the dryer is hidden in the body. 11A and 11B show an image after receiving a millimeter wave signal using FIGS. 10A and 10B as the search ranges, respectively. 11A and 11B, it can be seen that the dryer 20 is displayed in FIG. 11B unlike FIG. 11A. The image of FIG. 11 has a size of 20 × 20 pixels.

12A and 12B show an enlarged process of FIGS. 11A and 11B by a bicubic enlargement method. 13A and 13B are enlarged processes of Figs. 11A and 11B by a bilinear enlargement method. As illustrated in FIGS. 12 and 13, it is possible to enlarge the size of the measured image illustrated in FIG. 11 so that it is easy to determine whether there is a hidden object.

14A and 14B are enlarged processes of Figs. 11A and 11B by the inversion and bicubic magnification methods. 15A and 15B are enlarged processes of FIGS. 11A and 11B by an inverting and bilinear enlargement method. As illustrated in FIGS. 14 and 15, in order to display the hidden object more clearly, the size of the measured image illustrated in FIG. 11 may be inverted and enlarged. The images shown in FIGS. 12 to 15 have a size of 400 × 400 pixels.

16 is a flowchart of a millimeter wave imaging method according to an embodiment of the present invention. Referring to FIG. 16, a millimeter wave imaging method according to an embodiment of the present invention will be described in detail. The millimeter wave imaging method according to an embodiment of the present invention may be implemented by the millimeter wave imaging system according to an embodiment of the present invention described with reference to FIGS. 1 to 15.

First, a millimeter wave signal is received from the external search range 10 through the lens antenna 100 while automatically rotating the lens antenna 100 according to a predetermined rotation rule [S100]. The search range 10 may include at least one object. The rotation rule relates to at least one of a rotation angle, a rotation direction, and a time fixed at a specific position.

The step S100 may further include amplifying the received millimeter wave signal, converting the amplified millimeter wave signal into a DC voltage, and converting the converted DC voltage into a digital signal. .

In addition, the millimeter wave signal received in step S100 is configured as a millimeter wave image [S110]. As mentioned in the description of the millimeter wave imaging system according to an embodiment of the present invention, the execution time of the step S110 may vary. For example, the step S110 may be performed after the execution of the step S100 is completed for the entire search range 10. Also, for example, the step S110 may be performed after the step S100 is performed for a specific range of the entire search range 10. In this case, steps S100 and S110 may be repeatedly performed until the millimeter wave image is configured for the entire search range 10. In operation S110, the received millimeter wave signal may be configured as the millimeter wave image by using a difference between the voltage of the received millimeter wave signal and a preset reference voltage.

The millimeter wave image configured in step S110 is post-processed [S120]. In step S120, as described above, the millimeter wave image configured in step S110 is enlarged / reduced, inverted, enlarged / inverted, or reduced / inverted.

In addition, the millimeter wave image post-processed in step S120 is displayed on the display unit 155 [S130].

Other detailed features related to performing the steps S100 to S130 are the same as those described in the millimeter wave imaging system according to an embodiment of the present invention.

17 is a detailed flowchart of the step of receiving the millimeter wave by the rotation of the lens antenna. Referring to FIG. 17, an embodiment of the step S100 will be described in detail. The rotation rule is assumed to be based on FIG. 6.

First, the search range 10 is set [S200].

The set search range 10 is divided into N regions [S210]. For example, the search range 10 shown in FIG. 5 is divided into 25 regions.

Then set i to 1 [S220].

In addition, the lens antenna 100 is rotated such that the lens antenna 100 is directed to the i th region of the search range 10 [S230]. For example, the lens antenna 100 is positioned to direct the matrix components C1, R1 in FIG.

In addition, the millimeter wave signal is received from the i th region through the lens antenna 100 [S240]. For example, millimeter wave signals are received from the matrix components C1, R1 of FIG.

Then, it is determined whether i matches N [S250]. That is, step S250 is a step of determining whether the scan of the entire search range 10 is completed.

As a result of the determination in step S250, if i is less than N, i is increased by 1 [S260], and the flow returns to step S230. As a result of the determination of step S250, if i and N match, step S100 ends. In this manner, according to the rotation rule of FIG. 6, the lens antenna 100 may rotate and receive millimeter wave signals from all 25 regions of the search range 10 of FIG. 6 in order.

The millimeter wave imaging method according to the present invention described above may be provided by recording on a computer-readable recording medium as a program for executing on a computer.

The millimeter wave imaging method according to the present invention can be implemented through software. When implemented in software, the constituent means of the present invention are code segments that perform the necessary work. The program or code segments may be stored on a processor readable medium or transmitted by a computer data signal coupled with a carrier on a transmission medium or network. 18 is a diagram showing a screen example of software on which the millimeter wave imaging method according to the present invention is executed.

Computer-readable recording media include all kinds of recording devices that store data that can be read by a computer system. Examples of computer-readable recording devices include ROM, RAM, CD-ROM, DVD ± ROM, DVD-RAM, magnetic tape, floppy disks, hard disks, optical data storage devices, and the like. The computer readable recording medium can also be distributed over network coupled computer devices so that the computer readable code is stored and executed in a distributed fashion.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

1 is a schematic diagram of a millimeter wave imaging system according to an embodiment of the present invention.

2 is a view showing a state in which the millimeter wave image sensor module according to an embodiment of the present invention is actually implemented.

3 is a diagram illustrating an example of a lens antenna.

4 is a diagram illustrating a beam pattern of the lens antenna illustrated in FIG. 3.

5 is a diagram for describing an operation of scanning a search range through a lens antenna.

6 to 8 are diagrams for explaining the rotation direction of the lens antenna.

9A and 9B are graphs showing voltage graphs of millimeter wave signals over time.

10 is a diagram illustrating an example of a search range.

11A and 11B show an image after receiving a millimeter wave signal using FIGS. 10A and 10B as the search ranges, respectively.

12A and 12B show an enlarged process of FIGS. 11A and 11B by a bicubic enlargement method.

13A and 13B are enlarged processes of Figs. 11A and 11B by a bilinear enlargement method.

14A and 14B are enlarged processes of FIGS. 11A and 11B by an inversion and bicubic enlargement method.

15A and 15B are enlarged processes of FIGS. 11A and 11B by an inverting and bilinear enlargement method.

16 is a flowchart of a millimeter wave imaging method according to an embodiment of the present invention.

17 is a detailed flowchart of the step of receiving the millimeter wave by the rotation of the lens antenna.

18 is a diagram showing a screen example of software on which the millimeter wave imaging method according to the present invention is executed.

<Description of the symbols for the main parts of the drawings>

100: lens antenna 110: amplifier

120: detector 130: transducer

140: drive unit 145: memory

150: image processing unit 155: display unit

160: control unit 10: search range

Claims (17)

A lens antenna integrally formed with a lens and an antenna for receiving a millimeter wave signal radiated from at least one external object; A driving unit including a motor for rotating the lens antenna such that a direction in which the lens antenna is directed changes; An image processor configured to form a millimeter wave image of the millimeter wave signal received through the lens antenna; And A control unit configured to control the driving unit to rotate the lens antenna according to a predetermined rotation rule, and to configure the millimeter wave signal received at predetermined time intervals according to the rotation of the lens antenna into a millimeter wave image through the image processing unit; Including millimeter wave imaging system. The method of claim 1, wherein the rotation rule, Millimeter wave imaging system, characterized in that it relates to at least one of a rotation angle, a rotation direction, and a time fixed at a specific position. The method of claim 1, wherein the control unit, The millimeter wave imaging system of claim 10, wherein the lens antenna is rotated by controlling the driving unit until the reception of the millimeter wave signal is completed for a preset search range. The method of claim 3, wherein the image processing unit, And the millimeter wave image is configured as the millimeter wave image using the difference between the voltage of the millimeter wave signal received at the predetermined time interval and a preset reference voltage. The method of claim 4, wherein the image processor, And after the reception of the millimeter wave signal for the search range is completed, the millimeter wave imaging is configured for the entire search range. The method of claim 4, wherein the image processor, The millimeter wave imaging system, characterized in that the millimeter wave image is configured every time the millimeter wave signal is received at the predetermined time interval. The method of claim 1, Further including a display unit, The control unit, And a millimeter wave imaging system configured to display the millimeter wave image configured by the image processing unit on the display unit. The method of claim 1, An amplifier for amplifying and outputting the millimeter wave signal received through the lens antenna; A detector configured to convert the amplified signal into a direct current voltage and output the converted signal; And A converter for converting the DC voltage output from the detector into a digital signal and outputting Including more, The image processor, Millimeter wave imaging system, characterized in that for configuring the digital signal received from the transducer to the millimeter wave image. A lens antenna integrally formed with a lens and an antenna for receiving a millimeter wave signal radiated from at least one external object; An amplifier for amplifying and outputting the millimeter wave signal received through the lens antenna; A detector configured to convert the amplified signal into a direct current voltage and output the converted signal; And A driving unit including a motor for rotating the lens antenna such that the direction in which the lens antenna is directed changes; Including millimeter wave image sensor module. The method of claim 9, A converter for converting the DC voltage output from the detector into a digital signal and outputting Millimeter wave image sensor module further comprising. Receiving a millimeter wave signal emitted from at least one external object through the lens antenna while automatically rotating the lens antenna in which the lens and the antenna are integrally formed according to a predetermined rotation rule; And Configuring the received millimeter wave signal into a millimeter wave image Including millimeter wave imaging method. The method of claim 11, Displaying the configured millimeter wave image. Millimeter wave imaging method further comprising. The method of claim 11, wherein the rotation rule, A millimeter wave imaging method comprising at least one of a rotation angle, a rotation direction, and a time fixed at a specific position. The method of claim 11, wherein the millimeter wave image forming step comprises: The millimeter wave imaging method according to claim 1, wherein the millimeter wave signal receiving step is performed after the step of receiving the millimeter wave signal is completed for the entire preset search range. The method of claim 11, wherein the millimeter wave image forming step comprises: After the millimeter wave signal receiving step is performed for a specific range of all preset search ranges, And receiving the millimeter wave signal and the millimeter wave image forming step are repeated until the millimeter wave image is configured for the entire search range. The method of claim 11, wherein the millimeter wave image forming step comprises: The millimeter wave imaging method of claim 1, wherein the received millimeter wave signal is configured as the millimeter wave image by using a difference between the voltage of the received millimeter wave signal and a preset reference voltage. The method of claim 11, Amplifying the received millimeter wave signal; Converting the amplified millimeter wave signal into a direct current voltage; And Converting the converted DC voltage into a digital signal Including more, The millimeter wave image forming step, And a millimeter wave imaging method comprising the digital signal as the millimeter wave image.

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