2 results about "Angular distance" patented technology

A kind of relative navigation reference deviation calibration method of star and pulsar information fusion is disclosed, which comprises the following steps: configuring a star angular distance measuring sensor and an X-ray detector on a spacecraft; observing stars by the star angular distance measuring sensor to extract navigation information contained in two kinds of relativistic effects, i.e., star aberration caused by the movement of the spacecraft and light deflection caused by celestial gravitational field; observing pulsars by the X-ray detector to obtain pulse arrival time difference observations; combining spacecraft and earth orbit dynamics model to predict the state; processing star angular distance and pulse arrival time difference observations by an extended Kalman filter to correct the state prediction value, and obtaining the estimation of the spacecraft position and velocity, the geocenter position and velocity, and the sensor system error parameters, so as to realize the calibration of two kinds of reference deviations, i.e., earth ephemeris error and sensor system error. The present application provides a new way to improve the performance of relativistic navigation system.

The present application relates to remote sensing satellite ground data processing technical field, especially to a kind of multi-probe star camera internal and external parameter joint calibration method, the method, including constructing initial light direction model, and solving initial attitude parameter;Based on initial attitude parameter, the theoretical image coordinate of star control point is solved, and the relative installation relationship initial value between multi-probe star camera is determined after solving attitude parameter using star point data after gross error elimination;Based on the angular distance constraint between the star points in single frame image, a single-probe internal parameter calibration model and a joint calibration model with internal parameters and relative installation relationship as unknowns are constructed;According to the weighting model, the observation equation is weighted, the internal and external parameters are updated based on the solution, and the star camera accurate internal and external parameters are obtained by iterative optimization until the convergence condition is met.The present application effectively suppresses the influence of observation error on parameter solution, and further improves the calibration accuracy and the reliability of parameter estimation.