51 results about "Spaceborne radar" patented technology

The invention discloses a phase-scanning and mechanism-scanning combined airspace searching method based on a spaceborne radar. The method comprises the following steps of: (1) generating a searching wave beam with a fixed shape on an azimuth plane and first initiating the searching direction of an antenna array plane toward an azimuth dimension; (2) carrying out pitching dimension searching wave beam by using a pitching dimension-dimension phased array on the antenna array plane, and implementing pitching dimension airspace searching on a sine space by using characteristics of a phased array antenna wave beam; (3) rotating the antenna array plane to the position of a next azimuth angle; and (4) judging whether an azimuth dimension wave beam direction angle is rotated to a maximum searching azimuth angle direction or not and whether the pitching dimension airspace searching is finished or not; and if so, finishing the searching; and otherwise, carrying out the searching processes of the step (2) and the step (3) in a repeated way. According to the invention, an airspace searching method with different complementary and mixed searching methods as well as combined phase-scanning and mechanism-scanning of the spaceborne radar is achieved; and the phase-scanning and mechanism-scanning combined airspace searching method based on the spaceborne radar, disclosed by the invention, has the advantages of high searching speed, short target capturing time, uneasiness for losing targets, good impact shock resistance, less T / R units and suitability for being used on spaceborne platforms with finite resources.

The present invention relates to an advanced spaceborne Synthetic Aperture Radar (SAR) system and method that can provide high resolution measurements of the Earth or planetary surface, overcoming limitations in conventional SAR systems, and reduce development costs. The present invention utilizes advanced and innovative techniques, such as software defined waveforms, digital beamforming (DBF) and reconfigurable hardware, to provide radar capabilities not possible with conventional radar instruments, while reducing the radar development cost. The SAR system architecture employs a modular, low power, lightweight design approach to meet stringent spaceborne radar instrument requirements. Thus, the present invention can enable feasible Earth and planetary missions that address a vast number survey goals, including the measurement of ecosystem structure and extent, surface and sub-surface topography, subsurface stratigraphy, soil freeze-thaw, ice sheet composition and extent, glacier depth, and surface water, among many others.

A radar altimeter system-level testing method, using an echo simulator to form a closed-loop test system, to test the radar altimeter's height measurement function, wave height test function, and system AGC adaptive adjustment function, so as to test the system-level measurement function of the radar altimeter A comprehensive verification is carried out, which solves the system-level verification problem of the spaceborne radar altimeter under the whole star condition. The method of the present invention utilizes the echo simulator to form a closed-loop test system, changes the input of the radar altimeter system through the setting of the echo simulator and the adjustment of the attenuator, and interprets the final test result of the radar altimeter, and the test result reflects the complete working logic of the radar altimeter, achieving The purpose of radar altimeter system level verification.

The invention discloses a satellite-borne radar rainfall correction method based on active and passive microwave joint detection, and the method comprises the steps: correcting the deviation between active radar observation data and passive radiometer observation data in the presence of rainfall through employing numerical prediction background field historical data and observation historical data; performing space-time matching on the corrected active radar observation data, the corrected passive radiometer observation data and the numerical forecasting background field atmosphere three-dimensional space distribution information; using the numerical forecasting background field atmosphere three-dimensional space distribution information as prior information, and using the corrected activeradar observation data and the corrected passive radiometer observation data for calculation to obtain an optimal analysis atmosphere cloud and rain profile; and calculating a related rainfall correction coefficient of the active radar according to the optimal analysis atmospheric cloud and rain profile. The method is suitable for various satellite-borne radar systems and passive microwave instruments, and the precision of the rainfall correction coefficient can be guaranteed.

The invention discloses a spaceborne radar data processing and controlling device based on a VPX bus. Two identical processing computers are adopted for a data processing system and a controlling system, and each processing computer comprises two isomorphic PowerPC 440 cores. The two systems form two working modes through the four isomorphic PowerPC 440 cores. According to the parallel mode, the four isomorphic PowerPC 440 cores independently work, but interconnection channels are formed between the four isomorphic PowerPC 440 cores through interconnection communication buses. According to the fault-tolerance mode, the four isomorphic PowerPC 440 cores carry out fault tolerance in a four-mode redundancy mode. The device aims at achieving the purposes of high spaceborne radar data processing point flight path processing capacity, coordinate transformation of radar information data, trace point and flight path rough correlation, trace point and temporary flight path correlation, flight path correlation, trace point fusion and flight path filtering, and short prediction processing time and solving the problem that the spaceflight use environment is severe.

The invention relates to an InSAR deformation monitoring method based on spatial constraint, which comprises the following steps of: conducting data acquisition and preprocessing, namely, acquiring an original single-view complex image through a spaceborne radar satellite, and performing image registration and geocoding by using an external DEM to enable all the images to be positioned in a same coordinate framework; selecting an optimal main image from all the images under the same coordinate frame, and forming differential interference pairs by the optimal main image and other images respectively; based on the differential interference pair, selecting and obtaining high-coherence points; performing phase unwrapping processing on the high-coherence points to obtain unwrapped phases of the high-coherence points; for the unwrapping phase, inversing a deformation sequence by using spatial constraint, so as to obtain an initial deformation phase; and carrying out atmospheric error separation on the initial deformation phase to obtain a final deformation phase, namely deformation monitoring information. Compared with the prior art, the method is based on the time sequence InSAR technology, the spatial constraint is reasonably added, and the high-precision deformation sequence can be efficiently and reliably recovered.

The invention discloses a real-time compensation decoupling method for spacecraft platform disturbance by a spaceborne radar. The method includes that when the spaceborne radar searches, a three-axis stabilization rate gyroscope real-timely detects changing amount and changing direction of a spacecraft platform attitude angle; the changing amount and the changing direction of the spacecraft platform attitude angle are subjected to transformation of coordinates to obtain changing amount and changing direction of a spaceborne radar attitude angle; when the changing amount of the spaceborne radar attitude angle exceeds a preset threshold value, the spaceborne radar sets a searching compensatory angle; the value of the searching compensatory angle is the changing amount of the spaceborne radar attitude angle; the compensation direction of the searching compensatory angle is vertical to the searching direction of the spaceborne radar and opposite to the changing direction of the spaceborne radar attitude angle; a servo mechanism of the spaceborne radar performs real-time compensation controlling on the spaceborne radar attitude angle according to the searching compensatory angle. According to the real-time compensation decoupling method and a compensation decoupling system for spacecraft platform disturbance by the spaceborne radar, own resources of a spacecraft platform are utilized, real-time compensation of the servo mechanism of the spaceborne radar is achieved, valuable volume, weight, and power consumption resources of a spacecraft can not be occupied, and resources are saved.

The present invention relates to an advanced spaceborne Synthetic Aperture Radar (SAR) system and method that can provide high resolution measurements of the Earth or planetary surface, overcoming limitations in conventional SAR systems, and reduce development costs. The present invention utilizes advanced and innovative techniques, such as software defined waveforms, digital beamforming (DBF) and reconfigurable hardware, to provide radar capabilities not possible with conventional radar instruments, while reducing the radar development cost. The SAR system architecture employs a modular, low power, lightweight design approach to meet stringent spaceborne radar instrument requirements. Thus, the present invention can enable feasible Earth and planetary missions that address a vast number survey goals, including the measurement of ecosystem structure and extent, surface and sub-surface topography, subsurface stratigraphy, soil freeze-thaw, ice sheet composition and extent, glacier depth, and surface water, among many others.

The embodiment of the invention provides a multi-satellite formation radar timing synchronization method, device and equipment and a storage medium, which are applied to a multi-satellite formation spaceborne radar system. The spaceborne radar system comprises a primary satellite radar and at least one auxiliary satellite radar. The method comprises the following steps: acquiring relative time difference information between a second pulse signal output by a global navigation satellite system (GNSS) receiver of a primary satellite and a second pulse signal output by a GNSS receiver of any auxiliary satellite in at least one auxiliary satellite; according to the relative time difference information, performing time synchronization on the second pulse signal of the primary satellite and the second pulse signal of any auxiliary satellite; generating a timing signal of the main satellite radar and a timing signal of any auxiliary satellite radar based on the pulse per second signal after time synchronization. Based on the radar timing synchronization method provided by the invention, the time synchronization of the timing signals of the spaceborne radar system of the multi-satellite formation can be realized.

The invention discloses a phase-scanning and mechanism-scanning combined airspace searching method based on a spaceborne radar. The method comprises the following steps of: (1) generating a searching wave beam with a fixed shape on an azimuth plane and first initiating the searching direction of an antenna array plane toward an azimuth dimension; (2) carrying out pitching dimension searching wave beam by using a pitching dimension-dimension phased array on the antenna array plane, and implementing pitching dimension airspace searching on a sine space by using characteristics of a phased array antenna wave beam; (3) rotating the antenna array plane to the position of a next azimuth angle; and (4) judging whether an azimuth dimension wave beam direction angle is rotated to a maximum searching azimuth angle direction or not and whether the pitching dimension airspace searching is finished or not; and if so, finishing the searching; and otherwise, carrying out the searching processes of the step (2) and the step (3) in a repeated way. According to the invention, an airspace searching method with different complementary and mixed searching methods as well as combined phase-scanning and mechanism-scanning of the spaceborne radar is achieved; and the phase-scanning and mechanism-scanning combined airspace searching method based on the spaceborne radar, disclosed by the invention, has the advantages of high searching speed, short target capturing time, uneasiness for losing targets, good impact shock resistance, less T / R units and suitability for being used on spaceborne platforms with finite resources.

The invention discloses a GNSS-based radar height finding system and a using method thereof. The system comprises a signal hardware receiver and a server, wherein the signal hardware receiver is provided with three channels, respectively, a GNSS channel, a main radar channel and an auxiliary radar channel; each channel sequentially comprises an antenna assembly, a low-noise amplifier assembly, a frequency mixer assembly, a first-stage microwave signal source assembly, a band pass filter assembly, a power amplifier assembly, a second-stage microwave signal source assembly, a low pass filter assembly, a quadrature demodulator assembly, and an analog-to-digital converter assembly according to a signal passing direction. Signals of the three channels pass through the analog-to-digital converter assemblies and then together enter a data collector assembly. A data acquisition control software module, a signal pretreatment software module, a two-dimensional imaging software module and a coherent processing software module are loaded on the server. The system of the invention can solve technical limitations of single observation angle, expensive employment, long revisit period and the like in the current spaceborne radar height finding system.

The invention provides a fusion inversion method and device for a sea wave significant wave height field. The method comprises steps as follows: acquiring a significant wave height field which is acquired by a spaceborne radar height gauge and comprises substellar point sea wave significant wave height data as well as a sea surface wind field which is acquired by a spaceborne microwave scatterometer and comprises wide swath sea surface wind speed data; performing conversion calculation processing on the acquired sea surface wind field according to the wind wave growth relation between sea surface wind speeds and sea wave significant wave heights, and obtaining a wind wave field having the same swath as the sea surface wind field; performing correction processing on the wind wave field according to the acquired significant wave height field, and obtaining the sea wave significant wave height field having the same swath as the sea surface wind field; providing the sea surface wind field with wide swath, high precision and high spatial resolution through the spaceborne microwave scatterometer, converting the sea surface wind field acquired by the scatterometer into the wind wave field according to the wind wave growth relation, performing correction processing on the wind wave field through the significant wave height field of the height gauge, and finally, obtaining the significant wave height field with wide swath, high precision and high spatial resolution.

The invention provides an anisotropic sea surface radar back scattering simulation method and system. The method comprises the steps of: observing a data sample according to a plurality of satellite radars, carrying out fitting calculation on parameters in a to-be-configured anisotropic sea surface radar back scattering model which is established on the basis of a small slope approximation method,so as to obtain a configured anisotropic sea surface radar back scattering model, in the model, expressing asymmetric influences, on radar back scattering coefficients, of along wind and dead wind through a deflection function, and expressing autocorrelation of a sea surface height by adoption of an index-like type function; and obtaining data of a to-be-simulated field, and calculating and outputting a target radar back scattering coefficient corresponding to the data of the to-be-simulated scene according to the configured anisotropic sea surface radar back scattering model. According to the method and system, the characteristics of anisotropic sea surfaces can be truly reflected, and the calculation precision and calculation efficiency are both reasonably considered, so that the methodand system have important application value in the aspects of satellite-borne radar parameter design, sea surface wind field inversion and the like.

The embodiment of the invention provides a composite terrain feature simulation method and device and an electronic device, and the method comprises the steps: building a geological feature database and a digital elevation information database of a composite terrain, carrying out the orbit modeling of a satellite where a satellite-borne radar is located, and determining the conversion relation ofall coordinate systems of the satellite; determining an irradiation area of a radar beam of the satellite-borne early warning radar on the surface of the earth; and dividing an irradiation area according to the clutter scattering resolution to obtain a scattering unit; according to the target longitude and latitude corresponding to the scattering unit, obtaining geologic characteristics and elevation information of the scattering unit from a geologic characteristic database and a digital elevation information database respectively; and based on the geological characteristics and the elevationinformation of each scattering unit and the relative position relationship between each scattering unit and the radar, calculating the backward scattering coefficient of each scattering unit by adopting a calculation model, and taking the longitude and latitude, the geological characteristics, the elevation information and the backward scattering coefficient of each scattering unit as the composite terrain characteristics under the irradiation area.