Abstract: A method for identifying sunny and rainy moments by utilizing multiple characteristic quantities of high-frequency satellite-ground links is provided. The method may include the following steps of: extracting multiple characteristic quantities including standard deviation, trend, maximum value, minimum value, average value, skewness, kurtosis and information entropy; selecting an optimal time window through adjustment; and finally realizing the identification of the sunny and rainy moments by utilizing a classification algorithm. According to the method for identifying the sunny and rainy moments, sunny and rainy periods can be accurately distinguished by utilizing the signals of the high-frequency satellite-ground links, and real-time monitoring of large-range sunny and rainy distribution conditions is achieved.

Abstract: The complex temporal-spatial variation of raindrop size distribution will affect the precision of quantitative precipitation estimation (QPE) produced from radar data, making it difficult to correct echo attenuation. This invention presents a method for regional attenuation correction of weather radar using a multiple microwave links (ML) network. By measuring the rain attenuation of multiple microwave links in a specific frequency, matching with the weather radar in time and space and processed with discretization. Based on a series of attenuation values of the microwave link network and combined iterations, the attenuation coefficient of each grids is obtained; the total attenuation value of the path is obtained by combining the distance between the radar and each grid point, by which the reginal attenuation of radar echo can be corrected by the ML network efficiently.

Abstract: This invention discloses a method for measurement and 3D reconstruction of precipitation particles based on orthogonal dual-view imaging. An orthogonal 3D sampling space are formed by a pair of line camera and continuum light source, two pairs of planar cameras and pulse light sources placed orthogonally. The line camera scans with a speed no less than 20,000 lines per second, two cameras and pulse light sources are triggered when the line camera detects the particles in sampling area, two orthogonal images are recorded by two planar cameras using the double-exposure or multiple-exposure in one frame. The 3D images of particles are obtained by pixel matching and grid reconstruction method, based on which the 3D sizes, axis ratio, orientation, fall velocity, and other characteristics of particles are calculated. This method can measure the 3D micro-physical characteristics of precipitation particles automatically and precisely.

Abstract: The complex temporal-spatial variation of raindrop size distribution will affect the precision of quantitative precipitation estimation (QPE) produced from radar data, making it difficult to correct echo attenuation. This invention presents a method for regional attenuation correction of weather radar using a multiple microwave links (ML) network. By measuring the rain attenuation of multiple microwave links in a specific frequency, matching with the weather radar in time and space and processed with discretization. Based on a series of attenuation values of the microwave link network and combined iterations, the attenuation coefficient of each grids is obtained; the total attenuation value of the path is obtained by combining the distance between the radar and each grid point, by which the reginal attenuation of radar echo can be corrected by the ML network efficiently.

Abstract: This invention discloses a method for measurement and 3D reconstruction of precipitation particles based on orthogonal dual-view imaging. An orthogonal 3D sampling space are formed by a pair of line camera and continuum light source, two pairs of planar cameras and pulse light sources placed orthogonally. The line camera scans with a speed no less than 20,000 lines per second, two cameras and pulse light sources are triggered when the line camera detects the particles in sampling area, two orthogonal images are recorded by two planar cameras using the double-exposure or multiple-exposure in one frame. The 3D images of particles are obtained by pixel matching and grid reconstruction method, based on which the 3D sizes, axis ratio, orientation, fall velocity, and other characteristics of particles are calculated. This method can measure the 3D micro-physical characteristics of precipitation particles automatically and precisely.

Abstract: A method and video sensor for precipitation microphysical features measurement based on particle image velocimetry. The CCD camera is placed facing towards the light source, which forms a three-dimensional sampling space. As the precipitation particles fall through the sampling space, double-exposure images of precipitation particles illuminated by pulse light source are recorded by CCD camera. Combined with the telecentric imaging system, the time between the two exposures are adaptive and can be adjusted according to the velocity of precipitation particles. The size and shape can be obtained by the images of particles; the fall velocity can be calculated by particle displacement in the double-exposure image and interval time; the drop size distribution and velocity distribution, precipitation intensity, and accumulated precipitation amount can be calculated by time integration.

Abstract: A method and video sensor for precipitation microphysical features measurement based on particle image velocimetry. The CCD camera is placed facing towards the light source, which forms a three-dimensional sampling space. As the precipitation particles fall through the sampling space, double-exposure images of precipitation particles illuminated by pulse light source are recorded by CCD camera. Combined with the telecentric imaging system, the time between the two exposures are adaptive and can be adjusted according to the velocity of precipitation particles. The size and shape can be obtained by the images of particles; the fall velocity can be calculated by particle displacement in the double-exposure image and interval time; the drop size distribution and velocity distribution, precipitation intensity, and accumulated precipitation amount can be calculated by time integration.