Abstract: A GPU-based human body microwave echo simulation method includes: transmitting emulation input parameters from the memory of a CPU host into the display memory of a GPU device; configuring, at the CPU host, parallel computing network parameters to be run at the GPU device; initiating a kernel function for human body microwave echo simulation preset in the CPU host; computing the kernel function in parallel, in a plurality of processing kernels of the GPU device, in a multi-threaded manner, according to the parallel computing network parameters, to obtain simulation echoes of human body microwaves; transmitting the obtained simulation echoes of human body microwaves from the GPU device back to the CPU host. The method makes full use of the characteristic that a GPU can perform parallel computing to accelerate the echo simulation process, greatly improving the real-time performance of echo simulation of a human body microwave scanning and imaging system.

Abstract: A security check method includes: pre-creating at least four concurrently operating threads, one thread being responsible for movement control and data acquisition, one thread being responsible for imaging processing, one thread being responsible for interface displaying, and one thread being responsible for target detection and recognition; then the four concurrently operating threads divide original echo data of a human body to be checked into data of a plurality of adjacent overlapped azimuthal segments during data processing and perform individual processing on the data of each azimuthal segment. The security check system includes a thread creating unit, a first thread parallel unit, a second thread parallel unit, a third thread parallel unit, a fourth thread parallel unit, and a thread loop control unit. Because subsequent data processing is not required to be performed after the acquisition of all data is completed, the time for a security check process is reduced.

Abstract: A three-dimensional imaging system and method based on rotational scanning is disclosed. The system includes a column-shaped frame with a column-shaped side; a transceiving antenna array element arranged on the column-shaped side that transmits a micro-wave detection signal to a detected object located in the column-shaped frame and receives an echo signal reflected back from the detected object; a signal transceiving device that generates the micro-wave detection signal and sends same to the transceiving antenna array element and processes the echo signal; a rotation control device that controls rotational movement of the transceiving antenna array element so that the transceiving antenna array element transmits the micro-wave detection signal to the detected object in a plurality of angles; and a positioning trigger fixedly arranged on the column-shaped frame and configured to trigger the signal transceiving device when the transceiving antenna array element arrives at a position of the positioning trigger.

Abstract: A millimeter-wave real-time imaging based safety inspection system and safety inspection method. The safety inspection system includes a conveying device (10), a millimeter wave transceiver module (11), an antenna array (17, 18), a switch array (16a, 16b), a switch control unit (15a, 15b), a quadrature demodulation and data acquisition module (12), and an image display unit (13). By using an Inverse Synthetic Aperture Radar (ISAR) imaging principle, the millimeter-wave real-time imaging based safety inspection system performs real-time imaging on an object to be inspected when the object moves, so that not only the imaging speed is improved, but also the field of view is enlarged. A safety inspector can determine whether an inspected person carries dangerous goods by observing a three-dimensional diagram of the inspected person, thereby eliminating the inconvenience caused by back-and-forth movement of a safety inspection device used by the safety inspector around the inspected person.

Abstract: A portable security inspection device based on millimetre wave imaging comprising a hand-held body, wherein the hand-held body is provided with a millimetre-wave transmitting circuit for generating a millimetre-wave transmitting signal, a millimetre-wave array antenna for transmitting the millimetre-wave transmitting signal to a detected object and for receiving an echo signal reflected by the detected object, and a millimetre-wave receiving circuit for processing the echo signal and converting the echo signal into image data of the detected object.

Abstract: The invention belongs to the technical field of OCT and provides an OCT image processing device and system. An FPGA is in communication connection with an upper computer via a PCIE interface to receive OCT image data acquired by the upper computer and to carry out image preprocessing on the OCT image data and then send the OCT image data to the upper computer to display. The OCT image data is acquired and displayed by the upper computer and the OCT image data's preprocessing is implemented by the FPGA, so that the processing efficiency of the OCT image data is greatly improved.

Abstract: A millimeter wave security inspection instrument debugging system and a millimeter wave security inspection instrument debugging method, which are used for debugging the imaging definition of a millimeter wave holographic imaging security inspection system. A main control apparatus is used for generating a millimeter wave detection signal and a reference signal. The main control apparatus is also used for, where a millimeter wave transmitting antenna, a millimeter wave receiving antenna and a detected object are respectively located at different relative positions, transmitting the millimeter wave detection signal to the detected object by means of the millimeter wave transmitting antenna, and receiving an echo signal reflected from the detected object by means of the millimeter wave receiving antenna, and then using a holographic image technique to perform three-dimensional imaging according to the reference signal and the echo signal.

Abstract: The invention relates to a power adjustment method and apparatus, and a human body security check device. An adjustable power attenuator is provided in a millimeter wave signal transmitting link of the millimeter wave transceiver. The method comprises: obtaining a current humidity value by detecting the ambient humidity around the millimeter wave transceiver using a preset humidity sensor; determining a target power attenuation value of the adjustable power attenuator according to the current humidity value, the sum of the target power attenuation value and a power attenuation value caused to a millimeter wave signal by the ambient humidity being a constant value; and controlling the adjustable power attenuator to adjust its power attenuation value to be consistent with the target power attenuation value. The solution can reduce radiation hazard while ensuring the definition of an image.

Abstract: A terahertz metamaterial waveguide and device are provided. The terahertz metamaterial waveguide comprises a subwavelength substrate layer and a metal layer. One surface of the subwavelength substrate layer is plated with the metal layer, and a plurality of periodically-distributed micropores is formed in the metal layer. The subwavelength substrate layer, the metal layer, and the formed plurality of periodically-distributed micropores are described.

Abstract: A close range microwave imaging method and system is provided. The method comprises: controlling a linear antenna array consisting of a preset number of antennas to rotate along a preset arc trajectory so as to scan a target region; controlling the linear antenna array to acquire a preset number of echo data at azimuthal positions on the arc trajectory and to send an echo data set constituted by the preset number of echo data to a signal processing device until the linear antenna array completes the acquisition of echo data at preset azimuthal positions on the arc trajectory; and controlling, every time the signal processing device receives the echo data set, the signal processing device to perform imaging processing on the echo data set.

Abstract: A terahertz spectrum test device and system includes a femtosecond fiber laser configured to generate a pump light and a probe light. The pump light excites a terahertz transmitter to generate terahertz waves which are transmitted to a sample suspension device to irradiate a suspended to-be-tested sample, and the probe light is directly transmitted to a terahertz detector. The terahertz detector receives the terahertz waves transmitted from the sample suspension device, and then transmits the terahertz waves and the probe light together to a signal processing circuit to obtain a corresponding terahertz time-domain spectrum. By adoption of the terahertz spectrum test device and system, the to-be-tested sample need not be fixed with a clamp or other instruments, so that terahertz waves will not irradiate to the instrument used for fixing the to-be-tested sample during a terahertz spectrum test, which may otherwise affect the test result.

Abstract: An amplitude-phase correction method and system for a microwave imaging system are provided. The method comprises: carrying out data processing, in a range direction, on an echo signal reflected from a target object and acquired by a linear array antenna according to a first pre-set algorithm to obtain a compressed signal in the range direction; extracting a range value corresponding to the maximum amplitude, in the range direction, of the compressed signal in the range direction; carrying out time delay compensation on the echo signal according to the range value to obtain a time-delay-compensated signal; carrying out data processing on the time-delay-compensated signal according to a second pre-set algorithm to obtain an amplitude-phase signal; and carrying out amplitude-phase correction on the echo signal according to the time-delay-compensated signal and the amplitude-phase signal to obtain a corrected echo signal.

Abstract: An electrically scanned array antenna device applied to a millimeter wave imaging system is provided. The electrically scanned array antenna device comprises an adjustable light source for outputting an optical signal with an adjustable wavelength; an electro-optical modulation module; an optocouple; a time delay module for performing optical delay of different duration on each modulated signal, and correspondingly changing the duration of the optical delay according to the wavelength of the optical signal to obtain modulated signals of different phases; an optical detector; and an array antenna. The millimeter wave is loaded on the optical signal with an adjustable wavelength to obtain a modulated signal; the modulated signal is divided into multiple signals; time delay of different duration is performed on each signal; and millimeter wave signals of different phases are obtained after demodulation and are simultaneously transmitted to scan an object to be measured.

Abstract: The invention relates to a terahertz full polarization state detection spectrometer, which comprises a terahertz wave generator, a polarizer, a polarization splitter, a horizontal terahertz detector and a vertical terahertz detector. The terahertz wave generator generates a terahertz wave and the polarizer optimizes the terahertz wave for purity. The sample to be detected modulates the terahertz wave after purity optimization to obtain the terahertz modulated wave. The terahertz modulated wave is decomposed by the polarization splitter into a horizontal terahertz wave and a vertical terahertz wave whose polarization states are perpendicular to each other. The two terahertz waves are detected by two corresponding terahertz detectors respectively. According to the detected result, the characteristic of the sample is analyzed.

Abstract: Provided are a direct wave suppression method and system for a microwave imaging system. The method includes a series of filtering operations, such as conversion from a frequency domain to a time domain, filtering, conversion from the time domain to the frequency domain, and cancellation subtraction, on an echo signal set composed of echo signals obtained by a vertical linear array antenna at all the equivalent antenna collection positions thereof.

Abstract: A millimeter wave image based human body foreign object detection method, comprising: acquiring a millimeter wave gray scale image of a human body; according to a pre-determined foreign object imaging characteristic, extracting from the millimeter wave gray scale image a foreign object area image; according to a pre-determined foreign object image recognition algorithm, performing calculations on the foreign object area image, and acquiring a foreign object image from the foreign object area image; displaying the foreign object image as a foreign object detection result. Also provided is a millimeter wave image based human body foreign object detection system.

Abstract: A millimeter wave imaging apparatus, including: a crystal oscillator, a power divider, a millimeter wave transceiver, a local-oscillation signal processor, a second frequency mixer and an image processor; the power divider performs power distribution on an oscillation signal generated by the crystal oscillator, and outputs a clock trigger signal and a local-oscillation signal; the local-oscillation signal processor processes the local-oscillation signal and outputs a second local-oscillation signal; the millimeter wave transceiver unit processes an echo signal reflected by an object to be detected, and outputs a first intermediate-frequency signal; the second frequency mixer mixes the second local-oscillation signal and the first intermediate-frequency signal, and outputs a second intermediate-frequency signal; the image processor processes the second intermediate-frequency signal, and images the object to be detected.

Abstract: A plasmonic waveguide (10), a biosensor chip (100) and a system, wherein the plasmonic waveguide (10) is applied to the biosensor chip (100), and comprises a base (11) and a plasmonic structure (12) provided on the upper surface of the base (11); the plasmonic structure (12) comprises a plurality of plasmons (121) periodically arranged, the plasmons (121) being metal split rings, and the annular openings of the plasmons (121) being used for fixing antibody probes (122). The plasmon waveguide (10) is provided in the biosensor chip (100), the target biomolecules in the detection liquid flowing into a microfluidic channel (31) can be captured by means of the antibody probes (122), and the plasmonic waveguide (10) is used to enhance the signal strength of terahertz waves emitted to the biosensor chip (100), thereby enhancing the signal strength of the reflected terahertz waves detected by a terahertz analyzer (300), improving the detection sensitivity, the signal-to-noise ratio and the reliability.

Abstract: A terahertz full-polarization-state detection spectrograph is provided, which comprises a terahertz wave generator, a polarizer, a polarizing beam-splitting sheet, a horizontal terahertz detector, and a vertical terahertz detector. The terahertz wave generator produces a terahertz wave, and the purity of the terahertz wave is optimized by the polarizer; a detected sample modulates the terahertz wave, the purity of which is optimized, to obtain a terahertz modulated wave; the polarizing beam-splitting sheet decomposes the terahertz modulated wave into a horizontal terahertz wave and a vertical terahertz wave which are vertical to each other in a polarization state; the two corresponding terahertz detectors are used for detecting the two terahertz waves respectively, and then the characteristics of the detected sample are analyzed according to the detection result.

Abstract: A dynamic signal transmission structure based on a hybrid beamforming technology includes a radio-frequency module and an antenna array connected therewith. The radio-frequency module includes one or more radio-frequency link units connected in parallel, the antenna array includes one or more antenna sub-arrays, and each antenna sub-array is connected with one of the radio-frequency modules. The hybrid beamforming technology includes analog and digital beamforming. In this structure, the analog beamforming parameters and the digital beamforming parameters are constant, and the number of radio-frequency link units in the radio-frequency module, the number of antenna sub-arrays in the antenna array, the analog beamforming parameters, and the digital beamforming parameters are in a quantitative relation.