41results about How to "Improve data update rate" patented technology

The invention discloses a transmission line oscillation positioning system based on micro inertial measurement combination. The transmission line oscillation positioning system comprises a monitoring center and a pole and tower monitoring host machine which are connected with each other, wherein the pole and tower monitoring host machine is wirelessly connected with at least two wireless inertialsensor nodes; and each wireless inertial sensor node comprises a triaxial acceleration sensor and a triaxial gyroscope. By the method for positioning by adopting the system, the wireless inertial sensor nodes acquire acceleration values and state space angles of a lead wire monitoring point in three directions; the monitoring center processes and analyzes the data of each monitoring point by adopting algorithms, such as Fourier transformation, a least square method, digital filtering, Kalman filtering, matrix coordinate transformation, frequency domain integral operation so as to fit to acquire an oscillation trace of a whole line, and corrects the oscillation line according to a digital model of a relation between an oscillation characteristic value and a micro meteorological condition; therefore, the precision of oscillation monitoring is improved and the most direct and intuitive monitoring of transmission line oscillation can be realized.

The invention relates to a method for extracting fixed star image coordinates in real time based on a field programmable gate array (FPGA). According to the method, fixed star imaging of a star sensor adopts a sub pixel technology, the center of mass of the fixed star image coordinates is acquired through a center-of-gravity method, and only a gray value of the previous column of coordinates of the current row of the current image pixels and a gray value of the previous row of coordinates of the current column are adopted in the process of extracting the fixed star image coordinates. According to the method, after analog/digital (A/D) conversion is completely changed into digital quantity, the fixed star image coordinates of the image are immediately extracted. Therefore, the process that the star map data is required to be read from a static random access memory (SRAM) in the process of extracting the traditional fixed star image coordinates is avoided in the process of extracting the fixed star image coordinates. According to the method, the process of saving a star map to the SRAM and the process of extracting the fixed star image coordinates from the star map are completely parallel; and therefore, the time of extracting the fixed star image coordinates is reduced, the real-time property and the data updating rate are improved, and further the dynamic performance of the star sensor is further improved.

The invention relates to a method for rapidly processing the image of an APS sun sensor by an FPGA according to the following steps: establishing two shift registers and six register sets in the FPGA, wherein the two shift registers are used for storing label values, the six register sets are used for storing parameters obtained with the centroid method; establishing three processes in the FPGA to finish merging equivalent label regions and calculating the coordinate value in the energy center, wherein the three processes include an image label process P1, an image centroid method process P2 and a process P3; starting an image collecting process and an image processing process simultaneously by making full use of the characteristic of parallel processing in the FPGA, finishing extracting the effective data of one frame of image after finishing collecting the image, identifying the collected image of the APS sun sensor with the method for identifying 8 adjacent connected regions in the process of processing the image, obtaining the sun image which is formed on an image sensor through a light-ray introducing device, and calculating the effective image points in the same connected region with the centroid method in the process of identifying the adjacent connected regions to obtain the numerator and the denominator for calculating the coordinate value.

The invention discloses a high-precision attitude detection method of a static infrared earth sensor, which is used for carrying out attitude detection on spacecrafts running in a middle or high orbit. Based on such a feature that the imaging size of a horizon imaged on a focal plane changes significantly when the spacecrafts run at a height of the middle or high orbit, the invention designs a suitable image gridline scanning project, reads 8 rows and 8 columns of data of an infrared area array image and designs a corresponding high-precision attitude detection method, acquires the position of a horizon center, and outputs an attitude angle. A detailed attitude detection process is shown in figure 1. The high-precision attitude detection method of the invention solves the contradiction between huge amounts of data of a traditional static infrared earth sensor area array image and a limited storage capacity, having the advantages of small amount of data storage, high-precision attitude detection, high data updating rate, and the like.

The invention relates to a multilateral positioning system based on a distributed clock. The multilateral positioning system comprises one central station and at least four receiving stations; the central station and each receiving station respectively have a clock reference using an atomic clock as a core; the central station calculates the accurate position of a positioned target according to the signal arrival time difference of different receiving stations; the receiving stations are distributed at different positions on a target field; the receiving stations are mutually independent; furthermore, each receiving station is provided with a sensor used for receiving an answer signal given out by the target and recording an arrival moment; and the receiving stations carry out data communication with the central station through an optical fiber link. The multilateral positioning system provided by the invention adopts an advanced time difference positioning technique; the sense positioning precision of the multilateral positioning system is superior to 1 m; the three-dimensional positioning precision is superior to 5 m; and the sense monitoring requirements of large and medium complicated airports are met. The system is lower in construction cost and use cost, high in positioning precision and high in date replacement rate, is easy to erect, and can be widely used in the field of air traffic management and surveillance.

The invention provides a real-time star image mass center extraction method of a star sensor with a multi-output image sensor. The method comprises the following steps: judging whether a fixed star image exists on an edge of a component image in the process of extracting fixed star image coordinates, and directly calculating the corresponding star image coordinates by a gravity center method if the fixed star image does not exist on the edge of the component image, or if the fixed star image exists on the edge of the component image, saving a gray value of the fixed star image in the fixed star image coordinate extraction process, and saving edge information of the fixed star image; and finally, judging all pixels of which fixed star images are distributed in two component maps according to the edge information, and calculating the corresponding fixed star image coordinates of the fixed star images of which the pixels are distributed in the two component maps by the gravity center method. The method has a high real-time property, the data updating rate of the star sensor is improved, and the dynamic property of the star sensor is further improved.

The invention discloses a multi-channel differential multi-mode satellite navigation and positioning method and device. After receiving the difference information sent by the reference station and generating a check code, the master communication verification terminal sends the difference information and the verification code to the slave communication verification terminal. Verification terminal, the slave communication verification terminal performs integrity verification on the differential information according to the received differential information and verification code, the mobile station decides whether to send confirmation information to the master communication verification terminal according to the received verification result, the master The communication verification terminal maintains the current communication mode or switches the communication mode according to whether the confirmation information is received, and finally the mobile station calculates the positioning information and sends it to the reference station. By pre-checking the integrity of the differential information to determine which communication method to use, it can ensure that the differential information data does not leak packets, improve the positioning accuracy, and is suitable for multi-channel differential multi-mode satellite navigation positioning.

An encoding type sun sensor signal processing system based on an FPGA comprises the FPGA, a clock crystal oscillator, an AD converter and an analog switch, wherein the FPGA comprises a clock frequency divider module, a coarse code angle processing module, a fine code angle processing module and a coarse and fine code synchronization and data package module. The encoding type sun sensor signal processing system fully utilizes the advantages of the FPGA in parallel running system structure design and easy realization of a CORDIC quick optimization algorithm in the FPGA and remarkably improves the processing speed and the data update rate of an encoding type sun sensor, computation is simple, and projects are easy to achieve.

The invention relates to a star sensor with high data update rate, comprising an optical system and an electronic system. The optical system comprises an optical lens and a beam splitting prism. The electronic system comprises three EMCCD imaging units, data processing units connected in one-to-one correspondence with the EMCCD imaging units, an exposure timing control unit, and a data integrationand system monitoring unit. The beam splitting prism is used for respectively and uniformly projecting light passing through the optical lens to the three EMCCD imaging units for imaging in the EMCCDimaging unit. Each data processing unit is used for processing an image acquired by the corresponding EMCCD imaging unit. The exposure timing control unit is used for synchronously controlling the operation timing of the three EMCCD imaging units and the data processing units. The data integration and system monitoring unit is used for performing image output on the images of the data processingunits with the sum of the exposure frequencies of the three EMCCD imaging units. The invention can achieve the purpose of improving the data update rate of the star sensor.

The invention provides a ground-based synthetic aperture radar data noise reduction method, which comprises the following steps: S1, arranging at least two joint monitoring stations in a monitoring area of a ground-based radar, and arranging a Beidou differential reference station in a stable area; s2, correcting the deformation measurement value based on a vector projection distance weighted atmospheric correction method through the deformation measurement value of the ground-based radar measurement combined monitoring station, and obtaining a radar observation value after atmospheric correction; s3, obtaining a three-dimensional displacement measurement value of the combined monitoring station in real time through the Beidou differential reference station; and S4, fusing the radar observation value and the three-dimensional displacement measurement value after atmospheric correction by using a Kalman filtering algorithm to obtain a deformation value of the joint monitoring station. According to the method, the azimuth atmospheric effect is considered in radar atmospheric correction, and the defect that the azimuth atmospheric effect is not considered in an existing atmospheric correction algorithm is overcome; a ground-based radar and Beidou are adopted for data fusion, and advantage fusion of the ground-based radar and Beidou is achieved.

A combined imaging and driving method of a star sensor comprises the steps that window control words are generated and include driving control words and block control words, the block control words include row block control words and column block control words, the driving control words are used for representing an adopted full-frame driving mode or a window driving mode, the row block control words represent a row area of the position where a window is located, the column block control words represent a column area of the position where the window is located, window control words of a windowcontrol memory are read to judge a required driving mode, if the driving mode is the full-frame driving mode, all pixels are read row by row and one by one to obtain full-frame images, if the mode isa window driving mode, integral charge resetting is conducted on a detector, then exposure accumulation is performed, and finally window images are acquired according to the block control words in thewindow control words. The star point extracting capability is effectively improved, the posture effectiveness of the star sensor is guaranteed, computing quantity is decreased, a frame period is shortened, the data updating rate of the star sensor is improved, occupancy of resources is saved, and the dynamic performance of the star sensor is improved.

The invention, which relates to the technical field of the image processing method, discloses an FPGA-based on-satellite iterative image processing method comprising the following steps of: (1) carrying out image digitization; (2) constructing algorithm architecture; (3) giving algorithm parameters; (4) conducting algorithm iterative operation; (5) performing trial operation of algorithm operation; (6) correcting the algorithm architecture; and (7) comprehensively operating the algorithm architecture. According to the FPGA-based on-satellite iterative image processing method, an image processing algorithm containing iterative operation is embedded into the proposed algorithm architecture, so that the image processing algorithm can process multiple different types of CCDs, only FPGA resources for processing one CCD are occupied in the operation processing process, and the algorithm is small in occupied resources and high in operation efficiency; and the FPGA-based on-satellite iterativeimage processing method can be widely applied to an iterative algorithm, meets the design requirements, can effectively improve the utilization rate of FPGA resources, and makes full use of the advantages of the FPGA in parallel operation system structure design.