106 results about "Submillimeter wave" patented technology

A signal processor (30) for a submillimeter wavelength active radar system (10, 20, 30) processes signals received and downconverted by the radar system, the downconverted signals corresponding to a given pixel of the field of view having time varying amplitude and phase components which have a periodic component which is dependent on content. Information about the content is discriminated from the periodic component. By using phase rather than only amplitude, there is additional information in the downconverted signals. The phase is more sensitive to changes in the content such as objects, background and atmospheric conditions, than amplitude alone. The phase information enables the periodic component to be retained which can be characteristic of the content owing to content flutter, changes in submillimeter standing waves and interference fringes in received reflections of submillimeter illumination if surface layers have a thickness of a number of half wavelengths.

The invention relates to a microstrip bandpass filter with a sector open-circuit structure, belonging to the technical field of microwave/millimeter wave devices and relating to a microwave/millimeter wave integrated circuit. Based on a traditional parallel coupling microstrip line filter, the microstrip bandpass filter with the sector open-circuit structure adds two sections of sector open-circuit shunts; either sector open-circuited shunt is a one-fourth wavelength terminal open-circuit line with a sector-structure end terminal; and the start terminals of the two sections of sector open-circuit shunts are perpendicularly connected with a center point of an auxiliary microstrip line. The invention has the advantages of simple form, compact structure and high beyond-strip attenuation, not only can be used in a microwave/millimeter wave integrated circuit, but also can be used in a submillimeter wave band with higher frequency. Meanwhile, an input microstrip line and an output microstrip line of the microstrip bandpass filter with the sector open-circuit structure are on the same straight line, thereby facilitating the application in practical projects.

In driving of the vehicle, when an object unexpected by a driver suddenly appears at a close range in a traveling direction of the vehicle, a collision is liable to occur. A vehicle risk prediction apparatus includes: a first imaging unit that detects an electromagnetic wave of a wavelength ranging from a millimeter wave to a submillimeter wave to output a first image; a first detection unit that processes the first image output from the first imaging unit to detect a given object; and a risk prediction unit that outputs a detection result of the given object detected by the first detection unit. The first imaging unit includes: a transmit antenna unit that radiates the electromagnetic wave of the wavelength ranging from the millimeter wave to the submillimeter wave; a receive antenna array unit that has a plurality of receive antenna units arranged two-dimensionally, and receives a reflected wave of the electromagnetic wave radiated by the transmit antenna unit from the given object; and a signal processing unit that measures a time from radiation of the electromagnetic wave by the transmit antenna unit to reception of the reflected wave by the receive antenna array unit according to the number of read frames by the receive antenna array, and calculates both or any one of a distance from the subject vehicle to the given object, and a relative speed between the subject vehicle and the given object.

An antenna is provided that is configured to implement a combined radar and radiometric imaging method. The antenna comprises: a bearing device on which is rigidly mounted: rotating waveguide adapter which provides the output for the antenna; an electromechanical drive, the output shaft of which is defined as the main axis of rotation for the antenna and a position sensor. The antenna further comprises an antenna rotor, the rotation of which is configured to be controlled by the out-put shaft of the electromechanical drive of the bearing device. The antenna rotor comprises: at least one 2D diffraction grating; planar dielectric waveguide connected over a diffraction field to the 2D diffraction grating; a linear waveguide turn; and a feed adapter.

The invention relates to a holographic reflective array compact range. The holographic reflective array compact range is composed of a feed source, a reflective array antenna and edge teeth, wherein the feed source is fed forward and is vertically irradiated on the reflective array antenna, the reflective array antenna corrects spherical waves emitted by the feed source into plane waves at a close distance, and through caliber layout and inhibition of edge diffraction via the edge teeth, a specific plane wave dead zone is generated so that the far-field condition demand of an antenna pattern or a target RCS test is satisfied. According to the invention, the processing precision of the reflective array antenna is lower than a conventional reflection plane by one order of magnitude, a printing structure is employed, the structure is portable, the manufacturing is simple, the installation is convenient, the manufacturing cost can be decreased, and the holographic reflective array compact range is suitable for low-cost construction of a radiation or scattering test system of a millimeter wave/submillimeter wave band.

The invention relates to an ultra wide band submillimeter-wave frequency selection surface. The frequency selection surface of the invention adopts a thin sheet concatenation connection mode, improves the performance of the frequency selection surface, widens the band width, and improves the performance of the frequency selection surface on a transmission frequency band. A unit structure is in a circular shape, wherein the orthohexagonal period is used, the processing requirement is reduced, and the band width is widened. The invention has the following characteristics that: 1. the frequency selection surface has the ultra wide band; 2. the consumption is low; and 3. the frequency selection surface has the stability on different polarization. Thereby, the frequency selection surface designed through the method can be applied to the front end wave beam separation of a quasi-optical system as millimeter-wave and submillimeter-wave satellite remote sensing.

The invention provides a box-shaped fan-beam antenna. The box-shaped fan-bean antenna comprises a feed horn, a main cylindrical reflector, an auxiliary cylindrical reflector, an upper cover plate, a lower cover plate, a left baffle and a right baffle. The Cassegrain antenna geometric form is adopted in a bus of the main cylindrical reflector and a bus of the auxiliary cylindrical reflector, the upper side of the main cylindrical reflector, the lower side of the main cylindrical reflector, the left side of the main cylindrical reflector, the right side of the main cylindrical reflector, the upper side of the auxiliary cylindrical reflector, the lower side of the auxiliary cylindrical reflector, the left side of the auxiliary cylindrical reflector and the right side of the auxiliary cylindrical reflector form a box-shaped cavity through the upper cover plate, the lower cover plate, the left baffle and the right baffle respectively, the horn conducting feed on the box-shaped cavity is hidden inside the box-shaped cavity and a waveguide port in the rear portion of the horn serves as a feed port. The box-shaped fan-beam antenna can provide fan beams with a wide pitch (azimuth) range and a narrow azimuth (pitch) range, and is simple in structural form, easy to process and manufacture and very suitable for being applied to millimeter-wave and over-submillimeter-wave frequency bands.

The invention relates to a submillimeter wave FSS (frequency selective surface) with a loading fractal structure, wherein the submillimeter wave FSS has double frequency band-pass characters, the first central operating frequency is 424GHz, and the 3dB operating frequency is 387-452GHz; the second central operating frequency is 556GHz, and the 3dB operating frequency is 538-593GHz; the device is realized by an array consisting of multiple periodic resonance units, the center of each periodic resonance unit is provided with a Y-shaped three-arm seam, and one three-arm fractal seam pattern is loaded around each Y-shaped seam at every 120 degrees; and the FSS comprises a first silicon material layer, a first metal layer, a second silicon material layer, a second metal layer and a third silicon material layer, the structures of the five layers are cascaded, and the adjacent layers are tightly adhered.

The invention relates to a position detection method of a large-calibre millimetre wave/sub-millimetre wave telescope control system, comprising the following steps that: (1), an upper computer sends an instruction to a DSP (Digital Signal Processor) module; (2), coarse and fine channels of a double-channel multi-polar rotary transformer output a signal through a digital converter, and, after being subjected to level conversion, the signals are transmitted to the DSP module; (3), the DSP module calculates an absolute mechanical position signal of an arc motor, so that the closed loop of the arc motor is realized; (4), the DSP module converts the signal into an electrical angle, so that the current closed loop of the arc motor in vector control is realized; (5), the interior of the DSP module converts the signal obtained in the step (2) into A, B and Z signals in the form of coder through a software; (6), the A, B and Z signals are output through an IO interface of a DSP and sent to the DSP module through a serial interface after a CPLD (Complex Programmable Logic Device) module counts and judges the direction; and (7), the DSP module calculates the rotation speed and the steering direction of a motor according to a count value obtained in the step (6), so that the speed closed loop of the motor is realized. The position detection method disclosed by the invention can realize low-speed angular velocity of 1''/s and high-speed angular velocity of 12 DEG per s, without the low-speed creeping phenomenon.

The invention belongs to the technical field of centimeter-wave, millimeter-wave and submillimeter-wave high-efficiency compact aerial radiation field and target scattering testing systems, and discloses a high-efficiency compact aerial radiation field and target scattering testing system. The system comprises a high-efficiency compact field feed source. The high-efficiency compact field feed source is disposed on a fixed support. A forming reflection plane back support and a reflection plane off-ground angle adjustment support are connected together, and a forming reflection plane is installed on the forming reflection plane back support. The fixed support is connected with the forming reflection plane back support and the reflection plane off-ground angle adjustment support through a connecting rod. The system can remove nonuniform characteristics of a dead zone caused by an edge diffraction field of the reflection plane more effectively. Furthermore, the system reduces the level fluctuation of the dead zone.

A spectrometer energizes a solid state oscillator to generate a submillimeter wave and to sweep a predetermined band of frequency. The submillimeter wave is introduced into a sample cell that contains a gas, and frequency markers are electrically generated during the sweep. Outputs of a solid state detector disposed in the sample cell are read and recorded as a function of time and with the frequency markers. The recorded outputs of the solid state detector are converted into a function of frequency using the recorded frequency markers.

The invention discloses a traveling-wave regenerative-feedback oscillation system, belonging to the technical field of vacuum electrons. The oscillation system consists of noise, an electronic gun, an electron beam converging module, an isolator, a slow-wave circuit, a coupler, an attenuator, a phase shifter and a radio-frequency output module. Electron beams generated by the electronic gun are converged, and then acts mutually with the noise passing through the slow-wave circuit; amplified signals are output by the coupling end of the coupler and pass through the attenuator and the phase shifter, and the signals with the amplitude and the phase changed by the attenuator and the phase shifter act mutually with the noise and the electron beams again; and circulating so, the signals can pass through the coupler and are outputted by the radio-frequency output module, so that required radio-frequency signals are generated. The traveling-wave regenerative-feedback oscillation system disclosed by the invention overcomes the defects of difficult adjustment and instability of the output frequency in the prior art, has the advantages of high power and efficiency, low cost, small size, easy processing and implementation and the like, and has obvious advantages from submillimeter waves to the terahertz frequency band.

The utility model relates to a measuring system of broadband and high resolution millimeter wave signals and submillimeter wave signals, aiming at providing a measuring system to achieve the signal measuring of both the broadband and the high frequency resolution at the same time. The utility model adopts the technical proposal that: a superconducting SIS detector is arranged in the system to measure broadband signals by direct detection and the narrowband high resolution signal is measured through superhet frequency mixing; the measuring system realizes the analysis of broadband signal detection frequency through direct detection and realizes the analysis of narrowband high resolution signal detection frequency through superhet frequency mixing. The utility model adopts superconducting SIS detector, which is used as a frequency mixer in superhet frequency mixing method and as a direct detector in direct detection method, realizing the fast broadband scanning and the detection of narrowband high resolution frequency by the combination of the two methods of measuring the millimeter wave and submillimeter wave frequency signals.

The invention discloses an antenna near-field no-phase measurement method, wherein multiple near fields of a to-be-measured antenna can be accurately reconstructed through measuring an electric field amplitude value of a near-field scanning surface without direct measurement of phase information, and furthermore a far field directional diaphragm characteristic of the to-be-measured antenna is obtained. The antenna near-field no-phase measurement method aims to overcome the influence of the phase error to a measurement result in traditional near-field amplitude and phase measurement in a high-frequency working condition, and is a low-cost high-precision solution for near field measurement and aperture field diagnosis of high-frequency working antennae such as millimeter wave/submillimeter wave antenna and tera-hertz antenna.

The invention relates to a quadrature push-push voltage-controlled oscillator based on a circle structure. The oscillator comprises a four-stage delay unit, the phase relation between output signals in a circle oscillator constructed by a four-stage inverting amplifier is combined with a harmonic wave selection element to extract secondary harmonic waves in the output signals, mutually quadrature phases of the extracted secondary harmonic waves are used as the output of the circle structure so as to form the push-push voltage-controlled oscillator in quadrature output. Under the condition that the process is limited, the structure can effectively improve the frequency of the quadrature local oscillator output signal, and the structure can be used for providing a high-quality quadrature oscillator signal for millimeter wave, submillimeter wave, in particular a terahertz frequency band transceiving front end.

Generation of Terahertz range (300 GHz to 3 THz) frequencies is increasingly important for communication, imaging and spectroscopic systems, including concealed object detection. Apparatus and methods describe generating multiple phase signals which are phase-locked at a fundamental frequency, which are then interleaved into an output which is a multiple of the fundamental frequency. By way of example phase generators comprise cross-coupling transistors (e.g., NMOS) and twist coupling transistors (NMOS) for generating a desired number of phase-locked output phases. A rectifying interleaver comprising a transconductance stage and Class B amplifiers provides superimposition of the phases into an output signal. The invention allows frequency output to exceed the maximum frequency of oscillation of a given device technology, such as CMOS in which a 324 GHz VCO in 90 nm digital CMOS with 4 GHz tuning was realized.

The invention discloses a forward-looking radar scanning coherent imaging method. The forward-looking radar scanning coherent imaging method particularly includes enabling a high-speed platform to carry a scanning radar antenna, scanning space on the forward side of a desired track, transmitting millimeter-wave or submillimeter-wave linear frequency modulation signals and acquiring echo; and dividing the echo into a left portion and a right portion by using the right forward-looking direction as a boundary, respectively processing sub-blocks of data of the left portion and the right portion, removing Doppler centroid blurs of the sub-blocks of the data and performing coherent integration and connection for the sub-blocks of the data to finally implement high-resolution imaging for a forward-looking region. The forward-looking radar scanning coherent imaging method has the advantages that high-resolution imaging for the forward-looking region can be quickly and effectively implemented, constraints of scene types and limitation of the size of the platform are overcome, and problems of complexity in implementing synchronization, movement compensation and the like are solved.

The invention discloses a method for realizing target electromagnetic scattering characteristic modeling and analysis based on GPU parallel SBR. For a target of a submillimeter wave band, geometric modeling is firstly carried out to simulate the physical shape of the target, and triangular surface elements are used to divide grids. The method comprises steps of fitting the shape of the target by using a small number of triangular surface elements for the target part; subdividing the initial subdivision surface elements to meet the requirement of the SBR method on the aperture of the ray tube;meanwhile, in the process of judging occlusion, using self-adaptive subdivision for subdividing all partially occluded surface elements into an occlusion type and a non-occlusion type, then carrying out ray tracing and field intensity tracing on the subdivided ray tubes in parallel through a GPU to obtain RCS of the ray tubes, and obtaining the total RCS of the target by accumulating the RCS of all the ray tubes. For each ray tube, the frequency of intersection needing to be tested is greatly reduced, and the calculation time of the SBR method is shortened. For a flattened target, a small number of triangular surface elements can fit the surface shape of the target, and the method does not lose the calculation precision of the SBR method.