CN205450265U - Human security inspection system based on holographic three -dimensional imaging of millimeter wave - Google Patents

Abstract

The utility model discloses a human security inspection system based on holographic three -dimensional imaging of millimeter wave, including detecting room, mechanical scanning mechanism, millimeter wave signal transceiver unit, image processing unit and alarm unit, mechanical scanning mechanism is used for driving millimeter wave signal transceiver unit simultaneously in level and vertical direction for treating that the securair staff moves, millimeter wave signal transceiver unit is used for to treating that the securair staff launches the millimeter wave signal to the millimeter wave signal of receipt from treating the securair staff and reflecting, image processing unit is used for carrying out holographic three -dimensional imaging according to the human body that the securair staff was treated to the millimeter wave signal of reflection, obtains human three -dimensional image, the alarm unit is used for comparing the three -dimensional image of human body with the human three -dimensional image of safety who prestores in the alarm unit, if mismatch, then the police dispatch newspaper is sent out to the alarm unit. The utility model discloses a mechanical scanning replaces electric scanning, low price, simple structure, production cycle is short, high reliability and high resolution. The formation of image time is fast, the usage is very extensive.

Description

Human body security check system based on millimeter wave hologram three-dimensional imaging

Technical field

This utility model relates to a kind of human body security check system, particularly relates to a kind of human body security check system based on millimeter wave hologram three-dimensional imaging.

Background technology

In recent years, safety problem obtains the concern of the people of the world day by day, and reliability and intellectuality to safe examination system it is also proposed higher requirement.The least scope target can only be detected by traditional metal detector, and efficiency is low, can not meet the most far away the demand of safety check.Although the various ray such as X-ray has the strongest penetration power, but tested human body can be caused radiation injury, even if there is currently the X-ray machine of low radiation dose, but it is still not easy accepted by the public.Infrared ray is by body surface temperature imaging, cannot blur-free imaging in the case of having fabric to block.And millimeter wave imaging system is possible not only to detect the metal object being hidden under fabric, it is also possible to detect plastics pistol, the dangerous materials such as explosive, it is thus achieved that information more detailed, accurate, false alarm rate can be greatly reduced.Therefore, mm-wave imaging technology has obtained more being widely applied at aspects such as personnel's safety checks in recent years.

Millimeter wave imaging system typically has actively and passively two kinds of mode of operations.Passive millimeter wave PMMW (PassiveMillimeterWave) imaging system ultimate principle is based on any object the most ceaselessly radiated electromagnetic wave in nature, this electromagnetic wave is by the irrelevant wave component of different frequency, they are random, and there is the widest frequency spectrum and different polarised directions, different objects is different in the radiance of different-waveband.Passive millimeter wave imaging refers to rely on the atmospheric propagation window of 35GHz, 94GHz, 140GHz, 220GHz millimeter wave, receive the fine difference of target and the bright temperature of background to distinguish different object (Appleby.R., etal.IEEETransactionson, 2007,55 (11): 2944-2956).The bright temperature of target is mainly made up of 3 parts, i.e. self radiation, to the reflection of environment noise and the transmission of background noise.The material that relative dielectric constant is higher or conductivity is higher, radiance is less, and reflectance is higher.At that same temperature, the radiation temperature that high conductive material compares low conductive material is low, the coldest.

In general, passive millimeter wave imaging system is made up of reception antenna, millimeter wave radiometer, sweep mechanism and signal processing unit.The temperature resolution of system and spatial resolution are to weigh the important parameter of imaging effect.Relative to outdoor imaging, imaging indoors needs higher temperature resolution.

The mid-90 in last century, the U.S. began to carry out the research work of first generation millimeter wave radiometer imaging system, millimeter wave imaging system common problem in early days be exactly sweep time length, the problem such as sensitivity is not enough.The research institution of the representative achievement of passive millimeter wave focal plane array imaging system is all made that different counte-rplan and product for problem above.The Millivision of such as U.S. Millivision company detects door, and this system uses line Scan Architecture, and receptor is 4 rows, often row 64, adjacent two rows are longitudinally spaced be often arrange in two unit intervals 1/4.System is 1.92m × 0.768m at 1m far field, and resolution is 3mm × 3mm, and pixel is 640 × 256.Each image imaging time is 10s (HugueninG.Richard.SPIE, 1997,2938:152-159)；The commercial of Brojot company exploitation hides weapon detecting photographing unit in real time；3mm outdoor imaging system of FPA (focal plane arrays (FPA)) integrated by 1040 W-waveband receivers of TRW Ltd. (US) One Space Park, Redondo Beach CA 90278 U.S.A. etc..Although passive millimeter wave imaging system simple in construction, it is achieved cost is relatively low, but imaging time is oversize, and imaging resolution is relatively low, it is impossible to the most practical and commercialization, so a lot of research institution turns to the research of active MMW imaging system the most therewith.

Active MMW imaging system is made the rotation sweep 3D hologram millimeter wave imaging system of most preferably U.S. L-3 company at present, and the technological achievement of its research derives from U.S. Pacific Northwest National Laboratory PNNL (PacificNorthwestNationalLaboratoty).This system uses vertical direction array antenna, horizontal direction rotates the mode of 120 ° of scannings and produces human body front and back two width image (DouglasL.McMakin, etal.SPIE, 2007,6538:1-12), image algorithm is then the information obtained carries out holographic inversion calculating realize 3D hologram imaging.Technique has licensed to L-3Communications and SaveView company and has been commercially used for the large airport of each developed country, railway station and international harbour.But two row's dual-mode antenna arrays of this system include 384 Transmit-Receive Units altogether, and each column just has 192 Transmit-Receive Units, and structure is considerably complicated, and cost is the highest.

In addition to the laboratorys such as U.S. PNNL, the University Research Institute of country variant, company add in the research of mm-wave imaging technology the most gradually.Typically having Reading university of Britain, Germany's microwave and Radar Research Establishment (MicrowaveandRadarInstitute), aviation of Germany center (GermanAerospaceCenter), the ICT center of Australia and the NEC Corporation etc. of Japan, these research institutions the most once reported the achievement in research about mm-wave imaging.Domestic, the unit of research PMMW imaging system mainly has Space Sci. & Application Research Center, Chinese Academy of Sciences, National 863 plan microwave remote sensing technique laboratory, Institutes Of Technology Of Nanjing, the Central China University of Science and Technology, Southeast China University and Harbin Institute of Technology etc. at present.As mm-wave imaging technical research team of Institutes Of Technology Of Nanjing have developed Ka wave band alternative radiometer scanning imagery principle prototype (Xiao Zelong. millimeter wave to human body concealment article radiant image research [D]. Nanjing: Institutes Of Technology Of Nanjing, 2007), and be used for W-waveband DC radiometer scanning imagery hiding contraband detection carried out research work (Qian Songsong. the key technology research [D] of passive millimeter wave array detection imaging. Nanjing: Institutes Of Technology Of Nanjing, 2006)；The Central China University of Science and Technology is to the radiation characteristic of 3mm wave band, image-forming mechanism and improves the method for image resolution ratio and is analyzed, have studied the millimeter-wave radiation detection of metal target with identify and passive millimeter wave array detection imaging key technology (Zhang Guangfeng. Millimeter Wave Radiometric Characteristic and imaging research [D]. Wuhan: the Central China University of Science and Technology, 2005)；Antenna extended hemispherical lens for millimeter wave focal plane imaging is studied by the refined grade of millimeter wave key lab of Southeast China University Dou Wen, it is the mm-wave imaging experiment (WenbinDOU.IEICETransactionsonElectronics of concealed weapons, 2005, E88 (7): 1451-1456)；Harbin Institute of Technology's Qiu Jing brightness etc. have developed Ka wave band 20 passage millmeter wave focal imaging system prototype, it is possible to achieve indoor detection human body hidden objects etc..

In sum, existing millimeter wave human body imaging has several big shortcoming: for passive millimeter wave imaging system, and imaging rate is slow, differentiates rate variance；For active MMW imaging system, Transmit-Receive Unit is the most, and structure is complicated, with high costs.

Utility model content

The purpose of this utility model is slow for solving to be currently based on the human body security check system imaging rate of mm-wave imaging, differentiates rate variance, and Transmit-Receive Unit is many, baroque technical problem.

In order to solve above-mentioned technical problem, this utility model provides a kind of human body security check system based on millimeter wave hologram three-dimensional imaging, including sensing chamber, mechanical scanning mechanism, millimeter-wave signal Transmit-Receive Unit and graphics processing unit；

Described mechanical scanning mechanism is arranged in described sensing chamber, and described millimeter-wave signal Transmit-Receive Unit is arranged on described mechanical scanning mechanism, and the outfan of described millimeter-wave signal Transmit-Receive Unit connects described graphics processing unit；

Described mechanical scanning mechanism includes vertical scanner and horizontal sweep mechanism；

Described vertical scanner includes vertical guide rail and vertical distraction motor；Described vertical guide rail is a pair, the symmetrical both sides being located at described sensing chamber, and vertical guide rail is provided with groove towards the side treating security staff, and described transmitting antenna and reception antenna are fixed on slide block, and described slide block is embedded in described groove；Described vertical distraction motor drives described slide block along the upper and lower reciprocating motion of described vertical guide rail；

Described horizontal sweep mechanism includes horizontal gird and horizontally rotates motor；The two ends of described horizontal gird are fixing with the top of two described vertical guide rails respectively to be connected, described in horizontally rotate motor driving horizontal gird and vertical guide rail at horizontal rotation in surface.

Further, also including alarm unit, the outfan of described graphics processing unit connects described alarm unit.

Further, described millimeter-wave signal Transmit-Receive Unit includes that millimeter-wave signal transmitter unit and millimeter-wave signal receive unit；Described millimeter-wave signal transmitter unit includes millimeter-wave signal transmitter module and connected transmitting antenna, and described millimeter-wave signal receives unit and includes millimeter-wave signal receiver module and connected reception antenna；Described transmitting antenna and reception antenna are installed on described mechanical scanning mechanism, and relative to treating that security staff moves under the driving of described mechanical scanning mechanism.

Further, described millimeter-wave signal transmitter unit includes the first independent signal source, LFM Source, the first frequency mixer, the first broadband filter, the first frequency multiplication link and launches antenna；

The signal of described first independent signal source output and the signal of described LFM Source output send into the input of described first broadband filter after described first frequency mixer mixing, the outfan of the first broadband filter connects the input of described first frequency multiplication link, and the outfan of described first frequency multiplication link connects described transmitting antenna.

Further, described first frequency multiplication link includes the first power amplifier and the first varactor doubler, the outfan of described first broadband filter connects the input of described first power amplifier, the outfan of the first power amplifier connects the input of described first varactor doubler, and the outfan of described first varactor doubler connects described transmitting antenna.

Further, described millimeter-wave signal reception unit includes the second independent signal source, the second frequency mixer, the second broadband filter, the second frequency multiplication link, three-mixer, reception antenna, the 4th frequency mixer, the 5th frequency mixer, frequency tripling link and low-noise amplifier；

The signal of described second independent signal source output and the signal of described LFM Source output send into the input of described second broadband filter after described second frequency mixer mixing, the outfan of the second broadband filter connects the input of described second frequency multiplication link, the outfan of described second frequency multiplication link connects an input of described three-mixer, and another input of three-mixer connects described reception antenna；One input of described 4th frequency mixer connects described first independent signal source, another input of 4th frequency mixer connects described second independent signal source, the outfan of the 4th frequency mixer connects the input of described frequency tripling link, the outfan of frequency tripling link connects an input of described 5th frequency mixer, another input of 5th frequency mixer connects the outfan of described three-mixer, the outfan of the 5th frequency mixer connects the input of described low-noise amplifier, and the outfan of low-noise amplifier connects described graphics processing unit.

Further, described second frequency multiplication link includes the second power amplifier and the second varactor doubler, the outfan of described second broadband filter connects the input of described second power amplifier, the outfan of the second power amplifier connects the input of described second varactor doubler, and the outfan of described second varactor doubler connects described three-mixer.

Further, described frequency tripling link includes the 3rd power amplifier and the 3rd varactor doubler, the outfan of described 4th frequency mixer connects the input of described 3rd power amplifier, the outfan of the 3rd power amplifier connects the input of described 3rd varactor doubler, and the outfan of described 3rd varactor doubler connects described 5th frequency mixer.

Further, it is characterised in that described graphics processing unit includes that the low pass filter being sequentially connected with, in the same direction quadrature demodulator, video filter and data acquisition store processor.

Further, the sliding scale of described slide block is the top from the ground of described sensing chamber to sensing chamber.

Further, described horizontal gird and vertical guide rail are 0 °-120 ° at the angular range of horizontal rotation in surface.

Further, described first independent signal source is the operating frequency frequency modulation signal source at 20GHz-23GHz.

Further, described second independent signal source is the operating frequency frequency modulation signal source at 19.95GHz-22.95GHz.

This utility model the most existing mm-wave imaging safety check instrument has an advantage highlighted below:

(1) mechanical scanning is used to replace electric scanning, cheap: this utility model utilizes and horizontally rotates motor and carry out the scanning of horizontal circumference 120 ° and vertical scanning motor carries out the vertical scanning of vertical direction 2m, so two dual-mode antennas having only to both sides symmetrical just can complete the comprehensive scanning to human body, significantly reduce cost.

(2) simple in construction, with short production cycle: two motors used in this programme and the mechanical scan arrangement of a guide rail are the simplest, wherein horizontally rotating driven by motor vertical guide rail to horizontally rotate, two millimeter wave transceiving antennas of vertical distraction driven by motor realize moving up and down.

(3) resolution is high: uses the millimeter wave of 40GHz-46GHz frequency range owing to launching signal in this utility model and uses 3D hologram imaging algorithm so that imaging flat resolution reaches 3.75mm.

(4) imaging time is fast: horizontally rotating the speed of motor and vertical distraction motor by regulation in this utility model and control the time that millimeter-wave signal Transmit-Receive Unit is launched and received signal, being positioned at the dual-mode antenna on the vertical scanning guide rail of a length of 2m can complete a body scans at about 1s.

(5) purposes is widely: millimere-wave band of the present utility model can measure the metal object being hidden under fabric, can also detect that plastics pistol, the dangerous materials such as explosive, the information obtained is more detailed, accurate, false alarm rate can be greatly reduced, it is adaptable to airport, customs, high ferro station, Exhibition Centers, stadiums, the key post such as military-political.

Accompanying drawing explanation

Fig. 1 is the overall structure schematic diagram of one embodiment of this utility model；

Fig. 2 is millimeter-wave signal Transmit-Receive Unit of the present utility model and the schematic diagram of one embodiment of graphics processing unit；

Fig. 3 is utility model works flow chart；

Fig. 4 is the imaging algorithm flow chart that this utility model uses；

Fig. 5 is imaging schematic diagram of the present utility model.

In figure: horizontally rotate motor 1；Vertical distraction motor 2；Horizontal gird 3；Dual-mode antenna 4；Millimeter-wave signal transmitter module 5；Millimeter-wave signal receiver module 6；Graphics Processing Unit 7；Sensing chamber 8；Alarm unit 9；Treat security staff 10；Vertical guide rail 11；

First independent signal source 201；First frequency mixer 202；First broadband filter 203；First power amplifier 204；First varactor doubler 205；Launch antenna 206；LFM Source 207；Second independent signal source 208；Second frequency mixer 209；Second broadband filter 210；Second power amplifier 211；Second varactor doubler 212；Three-mixer 213；Reception antenna 214；4th frequency mixer 215；3rd power amplifier 216；3rd varactor doubler 217；5th frequency mixer 218；Low-noise amplifier 219；Low pass filter 220；Quadrature demodulator 221 in the same direction；Video filter 222；Data acquisition storage processor 223；First frequency multiplication link 224；Second frequency multiplication link 225；Frequency tripling link 226.

Detailed description of the invention

Presently in connection with accompanying drawing, this utility model is described in further detail.These accompanying drawings are the schematic diagram of simplification, and basic structure of the present utility model is described the most in a schematic way, and therefore it only shows the composition relevant with this utility model.

As shown in Figure 1, the human body security check system based on millimeter wave hologram three-dimensional imaging that this utility model provides, including sensing chamber 8, mechanical scanning mechanism, millimeter-wave signal Transmit-Receive Unit, graphics processing unit 7 and alarm unit 9, wherein mechanical scanning mechanism includes horizontally rotating motor 1, vertical distraction motor 2, horizontal gird 3 and vertical guide rail 11；Millimeter-wave signal Transmit-Receive Unit includes dual-mode antenna 4, millimeter-wave signal transmitter module 5 and millimeter-wave signal receiver module 6, as shown in Figure 2, dual-mode antenna 4 includes launching antenna 206 and reception antenna 214, millimeter-wave signal transmitter module 5 is connected with launching antenna 206, and millimeter-wave signal receiver module 6 is connected with reception antenna 214；The output signal of millimeter-wave signal receiver module 6 delivers to graphics processing unit 7, and the human body that graphics processing unit 7 treats security staff 10 according to this signal carries out hologram three-dimensional imaging, obtains the 3-D view of human body；The 3-D view of human body is compared by alarm unit 9 with the safe human body three-dimensional image being pre-stored in alarm unit 9, if not mating, then alarm unit 9 sends alarm.

Symmetrical two vertical guide rails 11 are divided into sensing chamber 8 both sides, and the two ends of horizontal gird 3 are connected to the top of two vertical guide rails 11, make horizontal gird 3 form a whole with two vertical guide rails 11.Treat that security staff 10 stands on the ground in sensing chamber 8, towards treating that the side of security staff 10 is provided with groove from top to bottom along guide rail on every vertical guide rail 11, groove extends to the top of sensing chamber 8 from the ground of sensing chamber 8, the a length of 2m of groove, groove is provided with slide block, slide block can slide up and down in whole groove, and dual-mode antenna 4 has a pair, is separately mounted on two slide blocks.Horizontally rotating motor 1 to be connected with horizontal gird 3, drive horizontal gird 3 and vertical guide rail 11 at horizontal rotation in surface, the angular range of rotation is 0 °-120 °；Vertical distraction motor 2 is connected with slide block, drives the dual-mode antenna 4 on slide block to move up and down, and the range of vertical motion in the groove of vertical guide rail 11 is the ground 0-2m away from sensing chamber 8.

Fig. 2 is millimeter-wave signal Transmit-Receive Unit of the present utility model and the schematic diagram of one embodiment of graphics processing unit, wherein millimeter-wave signal transmitter unit includes millimeter-wave signal transmitter module 5 and launches antenna 206, millimeter-wave signal transmitter module 5 includes the first independent signal source the 201, first frequency mixer the 202, first broadband filter 203 and the first frequency multiplication link 224, and the first frequency multiplication link 224 includes the first power amplifier 204 and the first varactor doubler 205.Millimeter-wave signal receives unit and includes millimeter-wave signal receiver module 6 and reception antenna 214, and millimeter-wave signal receiver module 6 includes second independent signal source the 208, second frequency mixer the 209, second broadband filter the 210, second frequency multiplication link 225, three-mixer the 213, the 4th frequency mixer 215, frequency tripling link the 226, the 5th frequency mixer 218 and low-noise amplifier 219；Wherein the second frequency multiplication link 225 includes the second power amplifier 211 and the second varactor doubler 212；Frequency tripling link 226 includes the 3rd power amplifier 216 and the 3rd varactor doubler 217.Graphics processing unit 7 includes low pass filter 220, in the same direction quadrature demodulator 221, video filter 222 and data acquisition storage processor 223.

First independent signal source 201 is the operating frequency frequency modulation signal source at 20GHz-23GHz, its output signal inputs in the first frequency mixer 202 and is mixed with LFM Source 207, the first power amplifier 204 is inputted through the first broadband filter 203 after mixing, this link power is made to reach the input power safety range of the first varactor doubler 205, after the first varactor doubler 205, this link incoming frequency frequency multiplication is to 40GHz-46GHz, is finally radiated by transmitting antenna 206；Second independent signal source 208 is the operating frequency frequency modulation signal source at 19.95GHz-22.95GHz, and its output signal inputs in the second frequency mixer 209 and is mixed with LFM Source 207.

The the first independent signal source 201 received is mixed by the 4th frequency mixer 215 with the second independent signal source 208, difference frequency 0.05GHz inputs the 3rd power amplifier 216, this link power is made to reach the safety range of input power of the 3rd varactor doubler 217, after the 3rd varactor doubler 217, by frequency frequency multiplication to 0.1GHz, finally enter in the 5th frequency mixer 218.

Three-mixer 213 is three port devices, three ports are respectively RF, LO and IF, wherein local oscillator LO terminates the output signal of the second varactor doubler 212, the echo-signal of the reflection that radio frequency end input reception antenna 214 receives, medium-frequency IF end then exports the superheterodyne signal of local oscillator LO and radio frequency, this signal, with certain extraterrestrial target information, is input to the radio frequency end of the 5th frequency mixer 218.

The radio-frequency head of the 5th frequency mixer 218 inputs the down-conversion signal first with target information exported by three-mixer 213, local oscillator end LO inputs the 0.1GHz point-frequency signal exported by the 3rd varactor doubler 217, and medium-frequency IF end then exports the second time down-conversion signal with target information.

Intermediate-freuqncy signal faint after twice down coversion can be amplified by low-noise amplifier 219, improves the signal to noise ratio of output signal, the output signal input picture processing unit 7 of low-noise amplifier 219.

Graphics processing unit 7 includes having low pass filter 220, in the same direction quadrature demodulator 221 and the high-speed data acquisition card of video filter 222 and holographic imaging algorithm can be used to carry out the data acquisition storage processor 223 of image procossing, and data acquisition storage processor 223 can be selected for general purpose computer.As shown in Figure 4, high-speed data acquisition card is acquired after (step 401) processes by the echo-signal after amplifying and filtering with in mat formatted file input computer, then use matlab to carry out spatial domain by 3D hologram imaging algorithm and turn the Fourier transformation (step 402) of frequency domain, after carrying out a series of simplification merging (step 403) again, finally carry out frequency domain and turn the inverse Fourier transform (step 404-406) in spatial domain, the amplitude gathered in signal and phase information correspondence spatial domain Object Depth and size are carried out the Fourier transformation between time domain and spatial domain and inverse transformation, finally reduce target three-dimensional image.

During as it is shown on figure 3, use system described in the utility model to carry out personnel's safety check, treat that security staff 10 stands on the ground in sensing chamber 8, typically will be through following steps:

Step 301: horizontally rotate the uniform circular motion that motor 1 drives horizontal gird 3 and vertical guide rail 11 to carry out 0 ° to 120 ° in horizontal plane, simultaneously, dual-mode antenna 4 on vertical distraction motor 2 band movable slider carries out upper and lower linear uniform motion in the range of vertical direction 0-2m, transmitting antenna 206 in dual-mode antenna 4 is then launched millimeter wave and is opened to cylinder on the human body treating security staff 10 in sensing chamber 8, and human body carries out comprehensive millimeter wave scanning from top to bottom.

According to the countries in the world high distribution situation of the person, by length L of vertical guide rail 11_TBeing set as that 2m, the circle diameter R of cylindrical open sensing chamber 8 are set to 1.8m, sweep time, t was 1s, the speed v of vertical scanning motor 2_T, horizontally rotate the speed omega of motor 1.The speed of two motors all can realize control by presetting.

The speed of vertical scanning motor

Horizontally rotate the speed of motor

When standing in sensing chamber 8 until security staff 10, horizontally rotate motor 1 and vertical distraction motor 2 starts simultaneously at work, while i.e. horizontally rotating motor 1 uniform circular motion 120 °, vertical distraction motor 2 drives dual-mode antenna 4 to be arrived the bottom of guide rail 11 by the top downward uniform motion 2m of vertical guide rail 11, completes body scan work.After scanning work terminates, vertical distraction motor 2 then spends the 0.5s time speed rapidly with 4m/s to return to the top of vertical guide rail 11 from the bottom to top, continues the scanning of human body next time.

Step 302: the reception antenna 214 in dual-mode antenna 4 receives the signal with target information reflected by human body simultaneously, this signal high-speed data acquisition card in millimeter-wave signal receiver module 6 delivers to graphics processing unit 7；

Step 303: the high-speed data acquisition card in graphics processing unit 7 delivers to data acquisition storage processor 223 after gathering data, such as computer, restored the human body image information received in signal by holographic imaging algorithm；

Step 304: by the 3-D view of above-mentioned human body image information with the safe human body of the standard being pre-stored in alarm unit 9 is compared, see and whether mate；If coupling, when i.e. human body image information not existing suspicious region, assert and treat that security staff 10 is safe, then go to step 307；If not mating, when i.e. human body image information existing suspicious region, then proceed to next step；

Step 305: the alarm in alarm unit sends audible alarm；

Step 306: treat security staff 10 and carry out manual detection, get rid of potential safety hazard；

Step 307: the next man is carried out safety check.

So move in circles.

As shown in Figure 5, it is assumed that human body is positioned at the O point at rectangular coordinate system center, and human body axle center overlaps with Z axis, and human body imaging region is (x₀,y₀,z₀)=(R₀cos,R₀sin,Z₀) cylinder, wherein R₀For needing the radius of imaging region,Span be 0 to 2 π.The rail length moved in figure is L_T, i.e. the length of synthetic aperture along Z-direction is L_T, aperture center is positioned at z=Z_mPlane, vertical guide rail under the rotation of horizontal motor with radius as R circumferentially about human body axle center rotate, define the synthetic aperture in circumference θ direction.Definition (R, θ, Z) is the position of sampling, any image space P on human body_nCoordinate be (x_n,y_n,z_n), its corresponding scattering strength is σ (x_n,y_n,z_n)。

Signal launched by definition antenna is p (t), (t, θ, z) in territory, reception antenna records echo-signal and is

$s_n(t,\mathrm{\θ},z)=\mathrm{\δ}(x_n,y_n,z_n)\·p(t-\frac{2\sqrt{{(x_n-R\cos \mathrm{\θ})}^2+{(y_n-R\sin \mathrm{\θ})}^2+{(Z_m-z_n-Z)}^2}}{c})---\left(3\right)$

Time t is carried out Fourier transformation have

$S_n(\mathrm{\ω},\mathrm{\θ},z)=P\left(\mathrm{\ω}\right)\mathrm{\σ}(x_n,y_n,z_n)\·\exp (-j2k_{\mathrm{\ω}}\sqrt{{(x_n-R\cos \mathrm{\θ})}^2+{(y_n-R\sin \mathrm{\θ})}^2+{(Z_m-z_n-Z)}^2})---\left(4\right)$

Wave number k in formula_ω=ω/c.The echo-signal of target multiple point target echo-signals cumulative in being imaging interval under practical situation, signal amplitude is negligible along with the decay of distance, then makes P (ω)=1.

Spherical wave signal in above formula exponential term is decomposed into the form of plane wave signal, and definition Z_m-Z=z ' then has

$e^{-j2k_{\mathrm{\ω}}\sqrt{{(R\cos \mathrm{\θ}-x)}^2+{(R\sin \mathrm{\θ}-y)}^2+{(z^{\′}-z)}^2}}=\∫\∫e^{j\left(2k_r\cos \mathrm{\φ}\right(R\cos \mathrm{\θ}-x)+2k_r\sin \mathrm{\φ}(R\sin \mathrm{\θ}-y)+k_{z^{\′}}(z^{\′}-z\left)\right)}{\mathrm{d\φdk}}_{z^{\′}}---\left(5\right)$

The decomposition of spherical wave signal may be considered by being positioned at that (x, y, z) plane wave signal of the objective emission put is cumulative.The linear wave of plane wave component isWherein k_x、k_yAnd k_z′It is k_ωAlong the wavenumber components of change in coordinate axis direction in space wave number field.K is defined in X-Y plane_rWavenumber components is

After spherical wave signal breakdown (5) is brought into (2) simplification, echo-signal can be expressed as

In formula, the expression formula in { } is the three-dimensional Fourier transform of the target scattering function of nonuniform sampling, definition three dimensional fourier transform to forThen (6) formula can be rewritten as

The z on above formula both sides is carried out Fourier transformation obtain

Definition

F_σ′(2k_r,φ,k_z)≡F_σ(2k_rcosφ,2k_rsinφ,k_z)(8)

$g(\mathrm{\θ},k_r)\≡e^{j2k_{r}Rcos\mathrm{\θ}}---\left(9\right)$

Then have

S(ω,θ,k_z)=g (θ, k_r)*F_σ′(2k_r,φ,k_z)(10)

θ in formula (10) is carried out Fourier transformation, and replaces θ with ξ, then convolution becomes product

${\tilde{F}}_{{\mathrm{\σ}}^{\′}}(2k_r,\mathrm{\ξ},k_z)=\frac{S(\mathrm{\ω},\mathrm{\ξ},k_z)}{G(\mathrm{\ξ},k_r)}---\left(11\right)$

Formula (11) is carried out inverse Fourier transform obtain

$F_{\mathrm{\σ}}(2k_{r}cos\mathrm{\θ},2k_{r}sin\mathrm{\θ},k_z)=F_{\left(\mathrm{\ξ}\right)}^1\[\frac{S(\mathrm{\ω},\mathrm{\ξ},k_z)}{G(\mathrm{\ξ},k_r)}\]---\left(12\right)$

Denominator in formula (12) can be by carrying out numerical computations to formula (9) along the fast Fourier transform of angle, θ direction sampled data.2k in formula_rCos θ=k_x, 2k_rSin θ=k_y.Sampled data in space wave number field is non-equally distributed, therefore, before calculating the target scattering intensity that final inverse three-dimensional Fourier transform obtains under rectangular coordinate, needs at (k_x,k_y,k_z) space wave number field carries out the nonuniform sampling interpolation arithmetic to uniform sampling, then, under rectangular coordinate system, the target scattering intensity of reconstruct is

$\mathrm{\σ}(x,y,z)=F_{(k_x,k_y,k_z)}^{-1}\{F_{\mathrm{\ξ}}^{-1}\[S(\mathrm{\ω},\mathrm{\ξ},k_z)e^{-j\sqrt{4k_r^2{R}^2-{\mathrm{\ξ}}^2}}\]\}---\left(13\right)$

Above-mentioned derivation can illustrate that (ω, θ, (x, y z), finally realize millimeter wave hologram three-dimensional imaging z) to obtain scattering strength σ of target by echo data S.

With above-mentioned according to desirable embodiment of the present utility model for enlightenment, by above-mentioned description, relevant staff can carry out various change and amendment completely in the range of without departing from this utility model technological thought.The content that the technical scope of this utility model is not limited in description, it is necessary to determine its technical scope according to right.

Claims (13)

1. human body security check system based on millimeter wave hologram three-dimensional imaging, it is characterised in that include sensing chamber, mechanical scanning mechanism, millimeter-wave signal Transmit-Receive Unit and graphics processing unit；

Described sensing chamber treats security staff for receiving；

Described mechanical scanning mechanism is arranged in described sensing chamber, and described millimeter-wave signal Transmit-Receive Unit is arranged on described mechanical scanning mechanism, and the outfan of described millimeter-wave signal Transmit-Receive Unit connects described graphics processing unit；

Described mechanical scanning mechanism includes vertical scanner and horizontal sweep mechanism；

Described vertical scanner includes vertical guide rail and vertical distraction motor；Described vertical guide rail is a pair, the symmetrical both sides being located at described sensing chamber, and vertical guide rail is provided with groove towards the side treating security staff, launches antenna and reception antenna is fixed on slide block, and described slide block is embedded in described groove；Described vertical distraction motor drives described slide block along the upper and lower reciprocating motion of described vertical guide rail；

Described horizontal sweep mechanism includes horizontal gird and horizontally rotates motor；The two ends of described horizontal gird are fixing with the top of two described vertical guide rails respectively to be connected, described in horizontally rotate motor driving horizontal gird and vertical guide rail at horizontal rotation in surface.

Human body security check system based on millimeter wave hologram three-dimensional imaging the most according to claim 1, it is characterised in that also include alarm unit, the outfan of described graphics processing unit connects described alarm unit.

Human body security check system based on millimeter wave hologram three-dimensional imaging the most according to claim 1 and 2, it is characterised in that described millimeter-wave signal Transmit-Receive Unit includes that millimeter-wave signal transmitter unit and millimeter-wave signal receive unit；Described millimeter-wave signal transmitter unit includes millimeter-wave signal transmitter module and connected transmitting antenna, and described millimeter-wave signal receives unit and includes millimeter-wave signal receiver module and connected reception antenna；

Described transmitting antenna and reception antenna are installed on described mechanical scanning mechanism, and relative to treating that security staff moves under the driving of described mechanical scanning mechanism.

Human body security check system based on millimeter wave hologram three-dimensional imaging the most according to claim 3, it is characterized in that, described millimeter-wave signal transmitter unit includes the first independent signal source, LFM Source, the first frequency mixer, the first broadband filter, the first frequency multiplication link and launches antenna；

The signal of described first independent signal source output and the signal of described LFM Source output send into the input of described first broadband filter after described first frequency mixer mixing, the outfan of the first broadband filter connects the input of described first frequency multiplication link, and the outfan of described first frequency multiplication link connects described transmitting antenna.

Human body security check system based on millimeter wave hologram three-dimensional imaging the most according to claim 4, it is characterized in that, described first frequency multiplication link includes the first power amplifier and the first varactor doubler, the outfan of described first broadband filter connects the input of described first power amplifier, the outfan of the first power amplifier connects the input of described first varactor doubler, and the outfan of described first varactor doubler connects described transmitting antenna.

Human body security check system based on millimeter wave hologram three-dimensional imaging the most according to claim 4, it is characterized in that, described millimeter-wave signal receives unit and includes the second independent signal source, the second frequency mixer, the second broadband filter, the second frequency multiplication link, three-mixer, reception antenna, the 4th frequency mixer, the 5th frequency mixer, frequency tripling link and low-noise amplifier；

The signal of described second independent signal source output and the signal of described LFM Source output send into the input of described second broadband filter after described second frequency mixer mixing, the outfan of the second broadband filter connects the input of described second frequency multiplication link, the outfan of described second frequency multiplication link connects an input of described three-mixer, and another input of three-mixer connects described reception antenna；One input of described 4th frequency mixer connects described first independent signal source, another input of 4th frequency mixer connects described second independent signal source, the outfan of the 4th frequency mixer connects the input of described frequency tripling link, the outfan of frequency tripling link connects an input of described 5th frequency mixer, another input of 5th frequency mixer connects the outfan of described three-mixer, the outfan of the 5th frequency mixer connects the input of described low-noise amplifier, and the outfan of low-noise amplifier connects described graphics processing unit.

Human body security check system based on millimeter wave hologram three-dimensional imaging the most according to claim 6, it is characterized in that, described second frequency multiplication link includes the second power amplifier and the second varactor doubler, the outfan of described second broadband filter connects the input of described second power amplifier, the outfan of the second power amplifier connects the input of described second varactor doubler, and the outfan of described second varactor doubler connects described three-mixer.

Human body security check system based on millimeter wave hologram three-dimensional imaging the most according to claim 6, it is characterized in that, described frequency tripling link includes the 3rd power amplifier and the 3rd varactor doubler, the outfan of described 4th frequency mixer connects the input of described 3rd power amplifier, the outfan of the 3rd power amplifier connects the input of described 3rd varactor doubler, and the outfan of described 3rd varactor doubler connects described 5th frequency mixer.

9. according to the human body security check system based on millimeter wave hologram three-dimensional imaging described in claim 1-2 and any one of 4-8, it is characterized in that, described graphics processing unit includes that the low pass filter being sequentially connected with, in the same direction quadrature demodulator, video filter and data acquisition store processor.

Human body security check system based on millimeter wave hologram three-dimensional imaging the most according to claim 3, it is characterised in that the sliding scale of described slide block is the top from the ground of described sensing chamber to sensing chamber.

11. human body security check systems based on millimeter wave hologram three-dimensional imaging according to claim 10, it is characterised in that described horizontal gird and vertical guide rail are 0 °-120 ° at the angular range of horizontal rotation in surface.

12. human body security check systems based on millimeter wave hologram three-dimensional imaging according to claim 4, it is characterised in that described first independent signal source is the operating frequency frequency modulation signal source at 20GHz-23GHz.

13. human body security check systems based on millimeter wave hologram three-dimensional imaging according to claim 6, it is characterised in that described second independent signal source is the operating frequency frequency modulation signal source at 19.95GHz-22.95GHz.