WO2022162869A1 - 物体透視装置、制御回路、記憶媒体、および物体透視方法 - Google Patents
物体透視装置、制御回路、記憶媒体、および物体透視方法 Download PDFInfo
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Definitions
- the present disclosure relates to an object see-through device, a control circuit, a storage medium, and an object see-through method for seeing through an object.
- An object to be measured is irradiated with millimeter waves, terahertz waves, etc., and the reflected waves from the object are used to see through the object.
- This object fluoroscope irradiates an object with radio waves while moving a transmitting/receiving antenna for measurement along a determined path, receives reflected waves from scattering points of the object, and records time-series data of the reflected waves.
- the object perspective system generates a received waveform, which is the waveform of the received signal, by superimposing reflected waves with various waveforms received from various scattering points.
- the object see-through apparatus can estimate the waveform of the reflected wave from the scattering point at arbitrary coordinates on the measurement area.
- the object fluoroscopy apparatus provides observation points comprehensively in a measurement area, generates an estimated waveform of a reflected wave for each observation point, and generates an estimated waveform and a received waveform. By taking the correlation of , the reflection intensity from each observation point is mapped.
- the correlation value between the estimated waveform and the received waveform is obtained as a correlation vector with phase information. That is, the correlation vector indicates the correlation between the estimated waveform and the received waveform and has phase information.
- the object perspective system can obtain a high correlation value when the observation point and the scattering point are close to each other, and can obtain a low correlation value when there is no scattering point near the observation point.
- the object fluoroscopy apparatus When performing imaging using MF, the object fluoroscopy apparatus repeats the same measurement using radio waves of multiple frequencies, thereby reducing side lobes caused by the placement of the transmitting and receiving antennas and scattered objects around the measurement area. .
- a method of synthesizing images measured by radio waves of multiple frequencies there are a power synthesis method that integrates the magnitude of the correlation vector for each pixel, and a phase synthesis method that performs complex addition considering the phase information for each pixel. be.
- phase combining method achieves a higher sidelobe reduction effect than the power combining method, if the phases of the correlation vectors at the same observation point measured with radio waves of different frequencies are not matched exactly, the correlation vector will be lost during complex addition. will be canceled. For this reason, the phase combining method requires signal processing that considers the influence of the information on the positional relationship between the observation point and the transmitting/receiving antenna or the frequency characteristics of the measurement system.
- the millimeter-wave image processing device described in Patent Document 1 includes a signal processing device that performs signal processing on signals received using an antenna, and a calibration signal generator arranged outside the signal processing device.
- the calibration signal generator acquires phase offset information to be applied to the signal processing device, and the signal processing device corrects the phase of radio waves received by the antenna using the phase offset information.
- Patent Document 1 requires a calibration signal generator, which poses a problem of complicating the configuration of the apparatus.
- the present disclosure has been made in view of the above, and provides an object fluoroscopy apparatus that can accurately see through an object with a simple configuration even in an environment where an accurate distance to the object cannot be measured. With the goal.
- the present disclosure provides an object to be measured based on reflected waves of radio waves containing a plurality of frequencies irradiated to the object to be measured placed within a measurement area. , wherein a plurality of images are synthesized by performing complex addition for each pixel of the plurality of images obtained by performing imaging based on reflected waves. It is characterized by comprising a phase-synthesized image generation unit that generates a phase-synthesized image.
- the object fluoroscopy apparatus has the effect of being able to accurately fluoroscopy an object with a simple configuration even in an environment where an accurate distance to the object cannot be measured.
- FIG. 1 is a diagram showing a configuration of an object see-through apparatus according to a first embodiment
- FIG. FIG. 4 is a diagram for explaining another example of an antenna movement path applied by the object see-through apparatus according to the first embodiment
- FIG. 4 is a diagram for explaining received signal generation processing by the object perspective apparatus according to the first embodiment
- FIG. 4 is a diagram for explaining observation points set by the object perspective apparatus according to the first embodiment
- FIG. 4 is a diagram for explaining the correlation between the estimated reflected wave waveform and the received waveform calculated by the object perspective apparatus according to the first embodiment
- FIG. 4 is a diagram for explaining an update pattern of frequencies of high-frequency signals used by the object perspective apparatus according to the first embodiment
- FIG. 4 is a diagram for explaining the configuration of a quadrature detection unit included in the object perspective apparatus according to the first embodiment
- FIG. 2 is a diagram showing the configuration of a waveform recording unit included in the object fluoroscopy apparatus according to the first embodiment
- FIG. 4 is a diagram for explaining power-combined image generation processing by a power-combined image generation unit included in the object perspective apparatus according to the first embodiment
- FIG. 4 is a diagram for explaining calculation processing of a correction phase for each frequency by a correction phase calculation unit included in the object perspective apparatus according to the first embodiment
- FIG. 4 is a diagram for explaining a process of generating a phase-synthesized image by a phase-synthesized image generator provided in the object perspective apparatus according to the first embodiment; 4 is a flow chart showing a phase-combined image generation processing procedure by the object perspective apparatus according to the first embodiment;
- FIG. 10 is a diagram showing the configuration of an object see-through apparatus according to a second embodiment; 10 is a flow chart showing a phase-combined image generation processing procedure by an object perspective apparatus according to a third embodiment;
- FIG. 11 is a diagram for explaining combinations of observation coordinate sets calculated by the object perspective apparatus according to the third embodiment and the total sum of Euclidean distances in each combination;
- FIG. 4 is a diagram showing a configuration example of a processing circuit provided in the object perspective apparatus according to the first embodiment when the processing circuit is realized by a processor and a memory;
- FIG. 4 is a diagram showing an example of a processing circuit provided in the object perspective apparatus according to Embodiment 1 when the processing circuit is configured by dedicated hardware;
- FIG. 1 is a diagram showing a configuration of an object see-through device according to a first embodiment.
- the object fluoroscopy apparatus 10A irradiates radio waves of high frequency signals such as millimeter waves and terahertz waves to a radio wave scatterer (object) 30 to be measured, and uses reflected waves W from the radio wave scatterer 30 to detect the radio wave scatterer 30. It is a device that sees through the The object see-through device 10A sees through the radio wave scatterer 30 by performing imaging using MF.
- the object fluoroscopy apparatus 10A performs MF by a phase synthesis method using high-frequency signals of a plurality of frequencies.
- object see-through apparatus 10A sees through radio wave scatterer 30 under an environment in which an accurate distance to radio wave scatterer 30 cannot be measured.
- the object fluoroscope 10A includes a transmitting antenna 11, a receiving antenna 12, a quadrature detection section 21, a high frequency signal generating section 24, a waveform recording section 22, a position control section 25, and a frequency control section 23. .
- the object fluoroscopy apparatus 10A also includes a power composite image generator 26 , a correction phase calculator 27 , and a phase composite image generator 28 .
- the transmission antenna 11 may have a configuration different from that of the object see-through device 10A.
- the reception antenna 12 may be configured separately from the object see-through device 10A.
- the frequency control unit 23 controls the frequency of the high frequency signal output from the high frequency signal generation unit 24 by outputting a frequency command designating the frequency of the high frequency signal to the high frequency signal generation unit 24 .
- the frequency control unit 23 updates the frequency of the high frequency signal designated to the high frequency signal generation unit 24 with a predetermined pattern.
- the frequency control unit 23 outputs the frequency of the high-frequency signal indicated by the frequency command to the waveform recording unit 22 as frequency data.
- the high-frequency signal generating section 24 generates a high-frequency signal used for measurement according to the frequency command from the frequency control section 23 and outputs it to the transmitting antenna 11 and the quadrature detection section 21 .
- the output of the high frequency signal generator 24 is coupled to the local input of the quadrature detector 21 and the local input of the transmission antenna 11 .
- the high-frequency signal generator 24 supplies high-frequency signals of various frequencies to the transmission antenna 11 and the quadrature detector 21 .
- An example of the high frequency signal generator 24 is a high frequency signal generator.
- the transmission antenna 11 is a component that radiates the high-frequency signal output from the high-frequency signal generator 24 into space as radio waves.
- the transmitting antenna 11 irradiates a radio wave of a high frequency signal to the radio wave scatterer 30 to be measured.
- the transmitting antenna 11 for example, a horn antenna, a pattern antenna formed on a substrate, an array antenna composed of a plurality of antennas, or the like is used.
- the receiving antenna 12 is a component that receives the reflected waves W from the radio wave scattering bodies 30 .
- the receiving antenna 12 receives reflected waves W reflected by a plurality of radio wave scattering points such as the scattering points 1A to 1C and outputs them to the quadrature detection section 21 .
- the receiving antenna 12 for example, a horn antenna, a pattern antenna formed on a substrate, an array antenna composed of a plurality of antennas, or the like is used. Note that the receiving antenna 12 does not necessarily have to have the same structure as the transmitting antenna 11 .
- the position control unit 25 controls at least one of the position of the transmitting antenna 11 and the position of the receiving antenna 12 .
- Position control unit 25 may control the positions of both transmitting antenna 11 and receiving antenna 12, may control the position of only transmitting antenna 11, or may control the position of only receiving antenna 12. good.
- the position control unit 25 controls the position of the transmitting antenna 11 when the position of the receiving antenna 12 is fixed.
- the position control unit 25 controls the position of the receiving antenna 12 when the position of the transmitting antenna 11 is fixed.
- the position of the transmitting antenna 11 corresponds to the radiation direction of radio waves from the transmitting antenna 11.
- position control section 25 controls the positions of both transmitting antenna 11 and receiving antenna 12 will be described below. It is also assumed that the relative positions of transmitting antenna 11 and receiving antenna 12 remain unchanged, and position control section 25 moves transmitting antenna 11 and receiving antenna 12 together.
- the position control unit 25 is connected to a transport mechanism (not shown) on which the transmitting antenna 11 and the receiving antenna 12 are mounted, and controls the positions of the transmitting antenna 11 and the receiving antenna 12 by controlling the position of the transport mechanism. .
- the position control unit 25 moves the transmitting antenna 11 and the receiving antenna 12 along a predetermined antenna movement path 71, and outputs position data indicating the positions of the transmitting antenna 11 and the receiving antenna 12 to the waveform recording unit 22.
- the position data of the transmitting antenna 11 is a fixed value.
- the position data of the receiving antenna 12 is a fixed value.
- the position data output by the position control unit 25 to the waveform recording unit 22 corresponds to the movement command output by the position control unit 25 to the transport mechanism.
- the antenna movement path 71 is a path along a circle that is moved so as to surround the radio wave scatterer 30 to be measured. Note that the antenna moving path 71 is not limited to a route along a circle.
- FIG. 2 is a diagram for explaining another example of the antenna movement path applied by the object see-through apparatus according to the first embodiment.
- An antenna movement path 72 which is another example of the antenna movement path 71, is a path along which the transmitting antenna 11 and the receiving antenna 12 are moved vertically and horizontally within a specific plane. Assuming that the plane set in the antenna movement path 72 is the XY plane, the position control unit 25 variously combines the movement in the X direction and the movement in the Y direction to move the transmitting antenna 11 and the receiving antenna 12 in various ways within the XY plane. move in the direction of
- the object perspective apparatus 10A uses an XY stage that moves the transmitting antenna 11 and the receiving antenna 12 within the XY plane.
- the XY stage is a stage that can move in the X-axis direction and the Y-axis direction, where the two axes in a specific plane and perpendicular to each other are the X-axis and the Y-axis.
- the quadrature detector 21 down-converts the received signal obtained from the receiving antenna 12 with the high-frequency signal supplied from the high-frequency signal generator 24 to obtain a baseband signal, which is a complex signal.
- This baseband signal contains amplitude phase difference information, which is information on the amplitude difference and phase difference between the high frequency signal output from the transmitting antenna 11 and the reflected wave received by the receiving antenna 12 .
- the quadrature detection section 21 outputs the baseband signal containing the amplitude phase difference information to the waveform recording section 22 .
- An example of the quadrature detection unit 21 is a quadrature detection circuit.
- the waveform recording unit 22 records reception waveform data obtained by converting the baseband signal output from the quadrature detection unit 21 from an analog signal to a digital signal.
- the waveform recording unit 22 associates and records received waveform data including amplitude phase difference information, frequency data, and position data.
- the power-combined-image generator 26 uses the received waveform data, frequency data, and position data recorded in the waveform recording unit 22 to obtain a radio wave scatterer to be measured by an imaging method using a power-combined MF. Generate 30 power composite images.
- a power-combining image is an image generated by an imaging method using a power-combining MF.
- a correlation value between an estimated waveform and a received waveform that is, a correlation vector with phase information is calculated for each frequency for all observation points, and only the magnitude of the obtained correlation vector is calculated. It is a method of accumulating.
- the power combining method has the advantage that even if the phases of the respective correlation vectors are different, robust imaging can be performed because the phases are not considered.
- the coordinates indicating the position of the observation point with the maximum reflection intensity are the maximum reflection intensity coordinates.
- the power-combined image generation unit 26 outputs power-combined image data including the maximum reflection intensity coordinates to the correction phase calculation unit 27 .
- the corrected phase calculation unit 27 calculates the phase data for each frequency based on the combined power image output from the combined power image generation unit 26 and the received waveform data, frequency data, and position data recorded in the waveform recording unit 22.
- a correction phase Arg(c n ( ⁇ )) is calculated.
- the corrected phase calculator 27 searches for the maximum reflection intensity coordinates from the combined power image output from the combined power image generator 26, and calculates the corrected phase Arg(c n ( ⁇ )) at the maximum reflection intensity coordinates as the frequency Calculated for each
- the corrected phase calculator 27 outputs the corrected phase Arg(c n ( ⁇ )) for each frequency to the phase synthesized image generator 28 .
- the phase synthesized image generator 28 generates the corrected phase Arg(c n ( ⁇ )) for each frequency output from the corrected phase calculator 27, and the received waveform data, frequency data, and A phase synthesized image is generated from the position data.
- the phase-combined image generation unit 28 generates the phase-combined image by a phase-combined imaging technique.
- a phase-combined image is an image generated by an imaging method using a phase-combined MF.
- the phase-synthesized image generator 28 outputs the phase-synthesized image, which is the imaging result, to an external device such as a display device.
- FIG. 3A and 3B are diagrams for explaining reception signal generation processing by the object perspective apparatus according to the first embodiment.
- reflected waves from scattering points 1A to 1C at different positions have different waveforms.
- the receiving antenna 12 generates a received signal by superimposing the time-series data of the reflected waves.
- the receiving antenna 12 here generates a received waveform, which is the waveform of the received signal, by superimposing the reflected wave from the scattering point 1A, the reflected wave from the scattering point 1B, and the reflected wave from the scattering point 1C. do.
- the received signal is a signal obtained by superimposing reflected waves from all scattering points.
- the positional relationship between the position of the measurement area where the scattering points are arranged and the position of the transmitting antenna 11 and the receiving antenna 12, that is, the positions of the transmitting and receiving antennas are known, It is possible to estimate the waveform of the reflected wave from a certain scattering point.
- the position of the measurement area is registered in advance in the object fluoroscopy apparatus 10A.
- the position of the transmitting/receiving antenna corresponds to the position data that the position control section 25 causes the waveform recording section 22 to record.
- FIG. 4 is a diagram for explaining observation points set by the object see-through apparatus according to the first embodiment.
- the object fluoroscopy apparatus 10A comprehensively sets observation points at various positions within the measurement area.
- FIG. 4 shows a case where the object perspective apparatus 10A sets observation points 2A to 2C.
- the object perspective apparatus 10A maps the reflection intensity from each observation point by correlating the estimated waveform of the reflected wave and the received waveform.
- FIG. 5 is a diagram for explaining the correlation between the estimated waveform of the reflected wave and the received waveform calculated by the object see-through apparatus according to the first embodiment.
- the power composite image generation unit 26 of the object fluoroscopy apparatus 10A obtains the correlation between the estimated waveform of the reflected wave and the received waveform.
- the power composite image generator 26 here takes correlation between the estimated waveform of the reflected wave at the observation point 2A and the received waveform. Further, the power combined image generation unit 26 obtains the correlation between the estimated reflected wave waveform and the received waveform at the observation point 2B, and obtains the correlation between the estimated reflected wave waveform and the received waveform at the observation point 2C.
- the power composite image generator 26 maps the reflection intensity from each observation point based on the correlation result indicating the correlation value between the estimated waveform of the reflected wave and the received waveform.
- the correlation value in this case is obtained as a correlation vector with phase information. A high correlation value is obtained when the distance between the observation point and the scattering point is short, and a low correlation value is obtained when there is no scattering point near the observation point.
- the arrangement of the transmitting antenna 11 and the receiving antenna 12 and the scattered objects around the radio wave scatterer 30 side lobes can be reduced.
- the object fluoroscopy apparatus 10A When synthesizing images measured at a plurality of frequencies, the object fluoroscopy apparatus 10A has a power synthesis method that integrates the magnitude of the correlation vector for each pixel, and a phase synthesis method that performs complex addition in consideration of phase information for each pixel. use both methods.
- phase synthesis method unless the phases of the correlation vectors of the same observation point measured at different frequencies match exactly, the correlation vectors are canceled during complex addition.
- Signal processing is executed considering the positional relationship between positions and the influence of the frequency characteristics of the measurement system.
- the object perspective apparatus 10A synthesizes images measured at a plurality of frequencies by a phase synthesis method, the phase offset included in the observation system is removed so that the phases of the correlation vectors of the same observation point measured at different frequencies match. do. That is, in order to achieve phase synthesis, the object perspective apparatus 10A corrects the phase of the radio wave by subtracting the phase offset of the correlation vector that occurs when a certain pixel is measured at different frequencies from the phase of the measurement result. .
- the phase ⁇ (t, ⁇ ) of the received signal is It is represented by the following formula (1).
- the wavelength of the radio wave used for measurement is wavelength ⁇
- the fixed phase offset amount included in the measurement system at wavelength ⁇ is ⁇ ( ⁇ ).
- the estimated value ⁇ (t, ⁇ ) of the phase of the reflected wave from the observation point n at the time t that does not consider the fixed phase offset included in the measurement system is expressed by the following equation (2).
- ⁇ ⁇ indicates that a hat symbol is placed directly above “ ⁇ ”.
- E is the fixed error between the actual distance and the estimated value between the transmit and receive antenna positions and the observation point.
- Reflected wave y n (t, ⁇ ) from observation point n at time t and its estimated value y n ⁇ (t, ⁇ ) are obtained by the following formula (3 ) and equation (4), respectively.
- y n ⁇ indicates that a hat symbol is placed directly above "y n ".
- the correlation value c n ( ⁇ ) at the wavelength ⁇ and the observation point n is represented by the following equation (5).
- the object see-through apparatus 10A of the present embodiment utilizes the fact that the phase component of the correlation vector at each observation point depends only on the wavelength ⁇ of the radio wave used for measurement and does not depend on the location of the observation point.
- the object perspective apparatus 10A calculates, for each frequency, the phase Arg(c n ( ⁇ )) of the correlation vector at the coordinates (calibration coordinates) at which the reflection intensity greater than the specific value is obtained within the measurement area, and calculates this phase Arg(c n ( ⁇ )) is used as a correction phase when synthesizing frequencies.
- the object fluoroscopy apparatus 10A corrects the images for each frequency using the correction phase, and then synthesizes the images to generate a phase synthesized image. As a result, the object perspective apparatus 10A avoids cancellation of correlation vectors when phase-combining images acquired at different frequencies.
- FIG. 6 is a diagram for explaining update patterns of frequencies of high-frequency signals used by the object perspective apparatus according to the first embodiment.
- the horizontal axis of the graph shown in FIG. 6 is time.
- the vertical axis of the graph shown in the upper part of FIG. 6 is the transmitting/receiving antenna position, and the vertical axis of the graph shown in the lower part of FIG.
- the position control unit 25 moves the transmitting antenna 11 and the receiving antenna 12 at a constant speed.
- the update pattern PT of the frequency of the high-frequency signal as shown in FIG. 6, a pattern in which the frequency in a certain range is repeated stepwise with respect to the transmitting/receiving antenna position set by the position control section 25 can be considered.
- the upper graph in FIG. 6 shows a case where the position control unit 25 controls the positions of the transmitting antenna 11 and the receiving antenna 12 so that the positions of the transmitting and receiving antennas are P1, P2, and P3 in that order. ing.
- the graph shown in the lower part of FIG. 6 shows the case where the frequency control unit 23 controls the frequency so that the frequency increases stepwise from frequency F1 to frequency F2 to frequency F3.
- the frequency F1 is the frequency when the transmitting/receiving antenna position is the position P1.
- the frequency F2 is the frequency when the transmitting/receiving antenna position is the position P2
- the frequency F3 is the frequency when the transmitting/receiving antenna position is the position P3.
- the frequency control unit 23 again controls the frequency so that it increases stepwise to frequency F1, frequency F2, and frequency F3.
- the frequency control unit 23 repeats these processes.
- update pattern PT shown in FIG. 6 is an example, and the combination of frequencies and transmission/reception antenna positions may be rearranged, and the order of measurement may be changed.
- FIG. 7 is a diagram for explaining a configuration of a quadrature detection unit included in the object see-through apparatus according to the first embodiment; FIG.
- the quadrature detection section 21 has mixers 31 and 32 and a 90-degree phase section 33 .
- An example of the 90 degree phaser 33 is a 90 degree phaser.
- a high-frequency signal supplied from a high-frequency signal generating section 24 is locally input to the quadrature detection section 21 , and a received signal is input from the receiving antenna 12 .
- a high-frequency signal from high-frequency signal generator 24 is input to 90-degree phase section 33 and mixer 32 .
- a signal received from receiving antenna 12 is input to mixer 31 and mixer 32 .
- the 90-degree phase section 33 generates a high-frequency signal having the same frequency and a 90-degree phase difference from the high-frequency signal, and outputs the high-frequency signal to the mixer 31 .
- the high-frequency signal from the high-frequency signal generator 24 is input to the mixer 32 as it is, and the high-frequency signal from the high-frequency signal generator 24 is supplied to the mixer 31 with the same frequency and a phase difference of 90 degrees. is entered.
- the mixer 32 mixes the high-frequency signal from the high-frequency signal generator 24 and the received signal and outputs the mixed signal.
- the mixer 31 mixes and outputs a high frequency signal having a phase difference of 90 degrees and a received signal.
- the quadrature detection unit 21 down-converts the received signal output from the receiving antenna 12 to calculate a baseband signal (received waveform data) which is a complex signal, and outputs the baseband signal (received waveform data) to the waveform recording unit 22 .
- the waveform recording unit 22 is a memory for recording received waveform data, which is a complex signal output from the quadrature detection unit 21, position data output from the position control unit 25, and frequency data output from the frequency control unit 23. has a part.
- FIG. 8 is a diagram showing the configuration of a waveform recording unit included in the object fluoroscopy apparatus according to the first embodiment.
- the waveform recording unit 22 has a memory unit 41 that stores correspondence information 44 in which received waveform data represented by a complex signal, frequency data, and position data are associated with each other.
- the waveform recording unit 22 also has ADCs (Analog to Digital Converters) 42 and 43 that convert the complex signal output from the quadrature detection unit 21 into a digital signal and record it in the memory unit 41 .
- ADCs Analog to Digital Converters
- the ADC 42 converts the complex signal output from the mixer 31 of the quadrature detection section 21 into a digital signal and records it in the memory section 41 .
- the ADC 43 converts the complex signal output from the mixer 32 of the quadrature detection section 21 into a digital signal and stores it in the memory section 41 .
- the correspondence information 44 shown in FIG. 8 is information stored in the memory unit 41 when the transmitting/receiving antenna positions and frequencies shown in FIG. 6 are set.
- the frequency data, position data, and received waveform data stored in the correspondence information 44 are read by the power composite image generator 26, the corrected phase calculator 27, and the phase composite image generator 28.
- the received waveform r1 of the received waveform data corresponds to the frequency F1 of the frequency data and the position P1 of the position data.
- the power combined image generator 26 reads the received waveform data, frequency data, and position data recorded in the waveform recorder 22 .
- the power-combined image generator 26 generates a power-combined image using the received waveform data, frequency data, and position data recorded in the waveform recorder 22 .
- FIG. 9 is a diagram for explaining processing for generating a power-combined image by the power-combined-image generation unit included in the object perspective apparatus according to the first embodiment.
- FIG. 9 shows the relationship between the correspondence information 44, which is the data read from the waveform recording unit 22 by the power-combined image generation unit 26, and the power-combined image generated using the read correspondence information 44.
- FIG. 9 shows the relationship between the correspondence information 44, which is the data read from the waveform recording unit 22 by the power-combined image generation unit 26, and the power-combined image generated using the read correspondence information 44.
- the correspondence information 44 read from the waveform recording unit 22 by the power combined image generation unit 26 is information in which received waveform data, frequency data, and position data are associated with each other.
- the power combined image generation unit 26 groups the read correspondence information 44 into data of the same frequency, and generates an image using MF for each frequency.
- the power combined image generation unit 26 generates an image 51 from data of frequency F1, an image 52 from data of frequency F2, and an image 53 from data of frequency F3.
- the power combined image generation unit 26 combines the images generated for each frequency by the power combining method to generate one power combined image.
- FIG. 9 shows a case where the power combined image generation unit 26 combines the images 51 to 53 by the power combining method to generate one power combined image 55 .
- the corrected phase calculator 27 calculates a corrected phase for each frequency from the combined power image output from the combined power image generator 26, the received waveform data recorded in the waveform recording unit 22, the frequency data, and the position data. Calculate Arg(c n ( ⁇ )).
- FIG. 10 is a diagram for explaining calculation processing of a correction phase for each frequency by a correction phase calculation unit provided in the object perspective apparatus according to the first embodiment;
- FIG. 10 illustrates a case where the corrected phase calculator 27 calculates the corrected phase Arg(c n ( ⁇ )) for each frequency using the combined power image 55 and the correspondence information 44 .
- the corrected phase calculator 27 groups the read correspondence information 44 into data of the same frequency. Also, the corrected phase calculator 27 searches for the maximum reflection intensity coordinates of the power composite image 55 output from the power composite image generator 26 .
- the maximum reflection intensity coordinate is the observation point 2A.
- the corrected phase calculator 27 calculates the corrected phase Arg(c n ( ⁇ )) of the observation point 2A, which is the maximum reflection intensity coordinate, for each frequency. Specifically, the corrected phase calculator 27 calculates the phases of the frequencies F1 to F3 at the observation point 2A. The phases of the frequencies F1 to F3 at the observation point 2A are used for the correction phases Arg(c n ( ⁇ )) of the images 51 to 53 when generating the power combined image 55, respectively.
- the phase Arg(c n ( ⁇ )) of the frequency F 1 at the observation point 2A is used for the correction phase Arg(c n ( ⁇ )) of the image 51 when generating the power combined image 55 .
- the phase Arg(c n ( ⁇ )) of the frequency F2 at the observation point 2A is used for the correction phase Arg(c n ( ⁇ )) of the image 52 when generating the power combined image 55 .
- the phase Arg(c n ( ⁇ )) of the frequency F3 at the observation point 2A is used for the correction phase Arg(c n ( ⁇ )) of the image 53 when generating the power combined image 55 .
- the corrected phases of the frequencies F1 to F3 are indicated by the corrected phase Arg(c A ( ⁇ )).
- the phase synthesized image generation unit 28 generates the corrected phase Arg(c n ( ⁇ )) for each frequency output from the corrected phase calculation unit 27, the received waveform data recorded in the waveform recording unit 22, the frequency data, A phase synthesized image is generated from the position data.
- FIG. 11A and 11B are diagrams for explaining a process of generating a phase-synthesized image by a phase-synthesized-image generating unit included in the object perspective apparatus according to the first embodiment;
- FIG. 11 illustrates a case where the phase-combined image generator 28 generates the phase-combined image 56 using the corrected phase Arg(c n ( ⁇ )) and the correspondence information 44 .
- the phase synthesized image generation unit 28 groups the correspondence information 44 read from the waveform recording unit 22 into data of the same frequency, and generates images 51 to 53 using MF for each frequency. Note that the phase-combined image generator 28 may acquire the images 51 to 53 for each frequency using MF from the power-combined image generator 26 .
- the phase synthesized image generation unit 28 generates the correlation vector of each pixel for the images 51 to 53 created for each frequency by the correction phase Arg(c n ( ⁇ )) for each frequency calculated by the correction phase calculation unit 27.
- a phase synthesized image 56 is generated by performing reverse rotation and then performing complex addition. This phase synthesized image 56 corresponds to the image in the measurement area.
- the object perspective apparatus 10A calculates the phase Arg(c n ( ⁇ )) of the correlation vector for each frequency at the coordinate at which the reflection intensity greater than the specific value is obtained within the measurement area, for example, the maximum reflection intensity coordinate. do.
- the object fluoroscopy apparatus 10A uses this phase Arg(c n ( ⁇ )) as a correction phase Arg(c n ( ⁇ )), so that the correlation vector becomes Avoid being canceled.
- the object perspective apparatus 10A selects coordinates having a reflection intensity higher than a specific value, for example , to select the maximum reflected intensity coordinate.
- the object perspective apparatus 10A can use the correction phase Arg(c n ( ⁇ )) without placing a calibration signal generator in the measurement area and without installing a calibration scatterer at known coordinates.
- a phase composite image 56 can be generated at the measurement area.
- the calibration signal generator does not need to periodically generate the calibration signal. no need to stop measuring.
- the object fluoroscopy apparatus 10A does not need to install an RFID (Radio Frequency Identification) tag, which is an example of a scatterer for calibration, at an accurate position in the measurement environment, so the measurement environment is limited. no.
- RFID Radio Frequency Identification
- FIG. 12 is a flowchart of a process procedure for generating a phase synthesized image by the object perspective apparatus according to the first embodiment.
- the object fluoroscopy apparatus 10A receives reflected waves while changing the frequency and the position of the transmitting/receiving antenna, and records received waveform data, which is information on the reflected waves (step S10).
- the position control unit 25 controls the position of the transmitting/receiving antenna, and the frequency control unit 23 controls the frequency.
- the receiving antenna 12 Upon receiving the reflected wave from the radio wave scatterer 30 , the receiving antenna 12 outputs the received signal to the quadrature detection section 21 .
- the quadrature detector 21 uses the received signal from the receiving antenna 12 and the high-frequency signal from the high-frequency signal generator 24 to generate a baseband signal, which is a complex signal.
- the waveform recording unit 22 generates and records received waveform data from the baseband signal. Further, the waveform recording unit 22 records the position data output by the position control unit 25 and the frequency data output by the frequency control unit 23 in association with the received waveform data.
- the power-combined image generation unit 26 generates a power-combined image using the received waveform data, frequency data, and position data recorded in the waveform recording unit 22 (step S20).
- the corrected phase calculator 27 searches for the maximum reflection intensity coordinates within the power combined image (step S30).
- the corrected phase calculator 27 calculates the phase of the correlation vector in the maximum reflection intensity coordinates as the corrected phase for each frequency (step S40).
- the phase-combined image generator 28 generates a phase-combined image using the corrected phase (step S50).
- the object perspective apparatus 10A performs complex addition for each pixel of a plurality of images obtained by performing imaging based on reflected waves from the radio wave scatterer 30. By doing so, a phase synthesized image is generated by synthesizing a plurality of images.
- the object fluoroscopy apparatus 10A can obtain the correction phase amount at each frequency, which is required when phase-combining images measured using a plurality of frequencies, without installing a calibration signal generator in the measurement area, or It can be obtained without installing a calibration scatterer at known coordinates. Therefore, even in an environment where the distance to the radio wave scatterer 30 cannot be accurately measured, the object see-through apparatus 10A can accurately see through the radio wave scatterer 30 with a simple configuration using radio waves of a plurality of frequencies. can.
- Embodiment 2 Next, Embodiment 2 will be described with reference to FIG. In Embodiment 2, transmitting antenna 11 and receiving antenna 12 are fixed, and radio wave scattering body 30 is moved.
- FIG. 13 is a diagram showing the configuration of an object see-through device according to the second embodiment. Among the constituent elements in FIG. 13, the constituent elements that achieve the same functions as those of the object see-through apparatus 10A of Embodiment 1 shown in FIG.
- the object fluoroscopy apparatus 10B has a different measurement system than the object fluoroscopy apparatus 10A.
- Object see-through apparatus 10B fixes transmitting antenna 11 and receiving antenna 12, and instead moves radio wave scatterer 30, which is an object to be measured.
- the object fluoroscopy apparatus 10B includes a turntable 50 on which an object to be measured is placed and which rotates.
- the position control unit 25 of the object fluoroscopy apparatus 10B controls the rotational position of the turntable 50.
- the radio wave scatterer 30 reflects radio waves at various positions.
- the receiving antenna 12 of the object see-through apparatus 10B receives the same reflected wave W as that of the object see-through apparatus 10A. Therefore, the object fluoroscopy apparatus 10B can generate a phase synthesized image by the same processing as the object fluoroscopy apparatus 10A.
- FIG. 13 shows a configuration in which the radio wave scattering body 30 is rotated by the turntable 50, but instead of the turntable 50, the XY stage described in FIG. Such a mechanism may be used to move the radio wave scattering body 30 .
- the object fluoroscopy apparatus 10B rotates the radio wave scatterer 30 using the turntable 50 and generates a phase synthesized image by the same processing as the object fluoroscopy apparatus 10A.
- the fluoroscopy apparatus 10B uses radio waves of a plurality of frequencies to accurately measure the distance to the radio wave scatterer 30 with a simple configuration.
- the radio wave scattering body 30 can be seen through.
- the transmission/reception antenna position of the object viewing apparatus 10B can be fixed, the movement of the wiring connecting the transmission antenna 11 and the high-frequency signal generator 24 and the movement of the wiring connecting the reception antenna 12 and the quadrature detection section 21 are not possible. No need to consider.
- Embodiment 3 differs from the first and second embodiments in the procedure for calculating the corrected phase in the corrected phase calculator 27 .
- the object see-through apparatus of Embodiment 3 may be the object see-through apparatus 10A or the object see-through apparatus 10B.
- the object see-through apparatus according to the third embodiment is the object see-through apparatus 10A.
- FIG. 14 is a flow chart showing a phase-combined image generation processing procedure by the object perspective apparatus according to the third embodiment.
- the object fluoroscopy apparatus 10A receives the reflected waves while changing the frequency and the position of the transmitting/receiving antenna, and records the received waveform data, which is the information of the reflected waves, by the same process as the process of step S10 described in the first embodiment. (Step S110).
- the power-combined-image generation unit 26 generates a power-combined image by the same processing as that of step S20 described in Embodiment 1 (step S120).
- the corrected phase calculation unit 27 calculates the top M (M is a natural number of 2 or more) observation coordinates having the highest reflection intensity from the coordinates of the observation points in the power synthesis image output by the power synthesis image generation unit 26, that is, the observation coordinates. Select (step S130).
- the correction phase calculator 27 extracts x (x is a natural number equal to or less than M) observation coordinates from the selected M observation coordinates.
- the corrected phase calculator 27 obtains the Euclidean distance of the corrected phase vector for l C 2 combinations of two observation coordinates selected from the extracted x observation coordinate set L.
- the corrected phase calculator 27 calculates the sum of Euclidean distances.
- the corrected phase calculator 27 calculates the sum of Euclidean distances for all M C x combinations, and selects the combination that minimizes the sum of the Euclidean distances of the corrected phase vectors. That is, the corrected phase calculator 27 selects x observation points having the closest phase for each frequency from the top M observation coordinates (step S140).
- the corrected phase calculator 27 calculates the average value of the corrected phase vectors of the selected observation points. That is, the corrected phase calculator 27 obtains a corrected phase vector for each frequency for each of the selected x observation points, and calculates the average value of the corrected phase vectors for each frequency (step S150).
- the corrected phase calculator 27 extracts the top M observation coordinates, and among the combinations of the x observation coordinates included in the top M observation coordinates, the combination with the smallest phase difference for each frequency is Extract the x number of observed coordinates. Furthermore, the corrected phase calculator 27 calculates the average value of the phases for each frequency as the corrected phase for the extracted x observation coordinates.
- the corrected phase calculator 27 uses the calculated average value of the corrected phase vectors as the corrected phase for each frequency to be output to the phase composite image generator 28 .
- the corrected phase calculator 27 generates a phase synthesized image using the corrected phase (average value of corrected phase vectors) obtained for each frequency for x observation points (step S160). Note that x may be the same value as M.
- FIG. 15 is a diagram for explaining combinations of observation coordinate sets calculated by the object perspective apparatus according to the third embodiment and the sum of Euclidean distances in each combination.
- the object perspective apparatus 10A can use information of a plurality of observation points to calculate the correction phase. It becomes possible to obtain stably.
- the hardware configuration of the object perspective apparatuses 10A and 10B will be described. Since the object see-through apparatuses 10A and 10B have the same hardware configuration, the hardware configuration of the object see-through apparatus 10A according to the first embodiment will be described below.
- the processing circuitry may be a processor and memory executing a program stored in the memory, or may be dedicated hardware. Processing circuitry is also called control circuitry.
- FIG. 16 is a diagram showing a configuration example of a processing circuit when the processing circuit included in the object perspective apparatus according to Embodiment 1 is implemented by a processor and a memory.
- a processing circuit 90 shown in FIG. 16 is a control circuit and includes a processor 91 and a memory 92 .
- each function of the processing circuit 90 is implemented by software, firmware, or a combination of software and firmware.
- Software or firmware is written as a program and stored in memory 92 .
- each function is realized by the processor 91 reading and executing the program stored in the memory 92.
- the processing circuit 90 has a memory 92 for storing a program that results in the execution of the processing of the object see-through apparatus 10A.
- This program can also be said to be a program for causing the object see-through apparatus 10A to execute each function realized by the processing circuit 90.
- FIG. This program may be provided by a storage medium storing the program, or may be provided by other means such as a communication medium.
- the above program can also be said to be a program that causes the object see-through apparatus 10A to execute the processes from steps S10 to S50 in FIG. That is, the program includes the steps of recording received waveform data, generating a combined power image, searching for the maximum reflection intensity coordinate, and calculating the phase of the correlation vector at the maximum reflection intensity coordinate as the corrected phase. and a step of generating a phase synthesized image using the corrected phase.
- the processor 91 is, for example, a CPU (Central Processing Unit), a processing device, an arithmetic device, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor).
- the memory 92 is a non-volatile or volatile memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable ROM), EEPROM (registered trademark) (Electrically EPROM), etc.
- RAM Random Access Memory
- ROM Read Only Memory
- flash memory EPROM (Erasable Programmable ROM), EEPROM (registered trademark) (Electrically EPROM), etc.
- a semiconductor memory, a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, or a DVD (Digital Versatile Disc) is applicable.
- FIG. 17 is a diagram showing an example of a processing circuit when the processing circuit included in the object perspective apparatus according to Embodiment 1 is configured with dedicated hardware.
- the processing circuit 93 shown in FIG. 17 is, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination of these thing applies.
- the processing circuit 93 may be partly implemented by dedicated hardware and partly implemented by software or firmware.
- the processing circuitry 93 can implement each of the functions described above by dedicated hardware, software, firmware, or a combination thereof.
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Abstract
Description
図1は、実施の形態1にかかる物体透視装置の構成を示す図である。物体透視装置10Aは、被測定対象である電波散乱体(物体)30にミリ波、テラヘルツ波などの高周波信号の電波を照射し、電波散乱体30からの反射波Wを用いて電波散乱体30を透視する装置である。物体透視装置10Aは、MFを用いたイメージングを行うことで、電波散乱体30を透視する。物体透視装置10Aは、複数の周波数の高周波信号を用いた位相合成方式でMFを実行する。なお、実施の形態1では、物体透視装置10Aは、電波散乱体30までの正確な距離を測定できない環境下で電波散乱体30を透視するものとする。
つぎに、図13を用いて実施の形態2について説明する。実施の形態2では、送信アンテナ11および受信アンテナ12を固定し、電波散乱体30を移動させる。
つぎに、図14を用いて実施の形態3について説明する。実施の形態3では、補正位相計算部27における補正位相の計算手順が、実施の形態1,2と異なる。
Claims (10)
- 測定エリア内に配置された被測定対象に対して照射された複数の周波数を含んだ電波の反射波に基づいて前記被測定対象の画像を生成する物体透視装置であって、
前記反射波に基づいたイメージングを行うことによって得られた複数の画像に対し、前記複数の画像の画素毎に複素加算を行うことで前記複数の画像を合成した位相合成画像を生成する位相合成画像生成部を備えることを特徴とする物体透視装置。 - 送信アンテナから放射され前記被測定対象で反射されて受信アンテナで受信された前記反射波の波形のデータである受信波形データ、前記被測定対象に対する前記送信アンテナおよび前記受信アンテナの位置を示す位置データ、および前記送信アンテナから放射される電波の周波数のデータである周波数データに基づき、前記反射波の推定波形と前記受信波形データとの相関を示す相関ベクトルを画素毎に積算する電力合成方式のマッチドフィルタを用いたイメージング方法によって前記周波数毎の前記被測定対象の画像を合成した電力合成画像を生成する電力合成画像生成部と、
前記電力合成画像、前記受信波形データ、前記位置データ、および前記周波数データに基づいて、前記電力合成画像で特定値よりも大きな反射強度を示す観測座標を探索する処理と、前記観測座標での前記相関ベクトルの位相を、前記画像を位相合成する際の位相の補正に用いる補正位相として算出する処理とを実行する補正位相計算部と、
をさらに備え、
前記位相合成画像生成部は、前記補正位相、前記受信波形データ、前記位置データ、および前記周波数データに基づき、前記相関ベクトルを画素毎に複素加算する位相合成方式のマッチドフィルタを用いたイメージング方法によって前記周波数毎の前記被測定対象の画像を合成した前記位相合成画像を生成する、
ことを特徴とする請求項1に記載の物体透視装置。 - 前記位相合成画像生成部は、
前記位相合成画像を生成する際に、前記相関ベクトルの位相オフセットから前記周波数毎に前記補正位相を差し引いて前記相関ベクトルを画素毎に複素加算する、
ことを特徴とする請求項2に記載の物体透視装置。 - 前記補正位相計算部は、
前記電力合成画像に含まれる前記観測座標のうち、最大の反射強度を示す最大反射強度座標を探索し、前記最大反射強度座標における前記周波数毎の位相を、前記補正位相として算出する、
ことを特徴とする請求項2または3に記載の物体透視装置。 - 前記補正位相計算部は、
前記電力合成画像に含まれる前記観測座標のうち、反射強度の上位複数個の観測座標を選定し、前記上位複数個の観測座標における前記周波数毎の位相の平均値を、前記補正位相として算出する、
ことを特徴とする請求項2または3に記載の物体透視装置。 - 前記補正位相計算部は、
前記上位複数個の観測座標に含まれる複数個の観測座標のうち、前記周波数毎の位相差が最も小さくなる組み合わせとなる複数個の観測座標を抽出し、抽出した複数個の観測座標における前記周波数毎の位相の平均値を、前記補正位相として算出する、
ことを特徴とする請求項5に記載の物体透視装置。 - 前記電波は、サブテラヘルツ帯からテラヘルツ帯の信号である、
ことを特徴とする請求項1から6の何れか1つに記載の物体透視装置。 - 測定エリア内に配置された被測定対象に対して照射された複数の周波数を含んだ電波の反射波に基づいて前記被測定対象の画像を生成する制御回路であって、
前記反射波に基づいたイメージングを行うことによって得られた複数の画像に対し、前記複数の画像の画素毎に複素加算を行うことで前記複数の画像を合成した位相合成画像を生成する処理を、前記被測定対象を透視する物体透視装置に実施させることを特徴とする制御回路。 - 測定エリア内に配置された被測定対象に対して照射された複数の周波数を含んだ電波の反射波に基づいて前記被測定対象の画像を生成するプログラムを記憶した記憶媒体であって、
前記プログラムは、前記反射波に基づいたイメージングを行うことによって得られた複数の画像に対し、前記複数の画像の画素毎に複素加算を行うことで前記複数の画像を合成した位相合成画像を生成する処理を、前記被測定対象を透視する物体透視装置に実施させることを特徴とする記憶媒体。 - 測定エリア内に配置された被測定対象に対して照射された複数の周波数を含んだ電波の反射波に基づいて前記被測定対象の画像を生成する物体透視方法であって、
制御回路が、前記反射波に基づいたイメージングを行うことによって得られた複数の画像に対し、前記複数の画像の画素毎に複素加算を行うことで前記複数の画像を合成した位相合成画像を生成する画像生成ステップを含むことを特徴とする物体透視方法。
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Publication number | Priority date | Publication date | Assignee | Title |
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JPH07120548A (ja) * | 1993-09-03 | 1995-05-12 | Mitsubishi Electric Corp | レーダ装置 |
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JP2007256171A (ja) | 2006-03-24 | 2007-10-04 | Nec Corp | ミリ波画像処理装置及びミリ波画像処理方法 |
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
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JP2007256171A (ja) | 2006-03-24 | 2007-10-04 | Nec Corp | ミリ波画像処理装置及びミリ波画像処理方法 |
Non-Patent Citations (3)
Title |
---|
See also references of EP4266030A4 |
WAKAYAMA, TOSHIO: "Technical Trends in Synthetic Aperture Radars.", THE JOURNAL OF THE INSTITUTE OF ELECTRONICS, INFORMATION AND COMMUNICATION ENGINEERS, vol. 95, no. 2, 30 November 2011 (2011-11-30), pages 142 - 144, XP009538965, ISSN: 2188-2355 * |
YULEI QIAN: "SAR Image Formation From Azimuth Periodically Gapped Raw Data Via Complex ISTA", IEEE CONFERENCE PROCEEDINGS OF ASIAN AND PACIFIC CONFERENCE ON SYNTHETIC APERTURE RADAR (APSAR, vol. 2019, no. APSAR, 2019, pages 1 - 5, XP033751297, DOI: 10.1109/APSAR46974.2019.9048466 * |
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