2 results about "Hour angle" patented technology

This invention provides a satellite onboard orbit conversion method and system. The method includes: calculating the corrected Julian day at the current time and calculating the Greenwich Mean Sidereal Time Angle based on the corrected Julian day; converting the Greenwich Mean Sidereal Time Angle into radians; calculating the Earth rotation matrix from the J2000 system to the WGS84 system based on the converted radians; pre-calculating the Earth nutation and precession correction matrices as modifiable parameters for satellite commands and updating them periodically; calculating the conversion matrix from the J2000 system to the WGS84 system based on the Earth nutation and precession correction matrices and the Earth rotation matrix; and calculating the satellite position and velocity in the WGS84 system based on the conversion matrix, thereby realizing the satellite onboard orbit conversion. This invention addresses the need for converting EP satellite onboard orbit information from an inertial frame to the WGS84 coordinate system, meets the requirements for short message stand-alone operation, and can provide a reference for on-orbit conversion of other satellites.

The invention provides a near-ground received radiation quantity calculation method, and belongs to the technical field of solar energy resource evaluation, and the method comprises the steps: S1, obtaining the historical data of astronomical parameters of a to-be-calculated region, the astronomical parameters comprise a radiation period, a solar constant, geographic latitude, a sun-earth distance, solar declination, sunrise and sunset hour angles, total ground radiation quantity, sunshine duration, half-day sunshine duration and astronomy difference; s2, dividing the historical data of the astronomical parameters into twenty-four groups according to solar terms; s3, based on grouping, 24 ground total radiation quantity calculation equations are constructed respectively; the historical data of the astronomical parameters are divided into twenty-four groups according to the solar term days over the years, the time range is refined through the ground total radiation quantity calculation formula of each group, the linear regression relation between the ground total radiation quantity and the sunshine percentage is accurately fitted, and the deviation between the measured data of the meteorological station and the formula calculation result is remarkably reduced.