A Mixed Distribution Model of Pointing Error of Aircraft

Abstract

In the space exploration mission, the aircraft will be affected by mechanical shocks, tracking noise and other factors to cause angular micro-vibration, so that the antenna pointing error is always non-zero, which will affect the communication link. Aimed at the disadvantage that typical single distribution models of pointing error such as Gaussian distribution, Rayleigh distribution and Rice distribution ignore the common impact of multiple error sources, a mixed distribution model of pointing error is proposed, which takes multiple error sources into account at the same time, and greatly improves the accuracy of the model. First, the pointing error signal is fitted according to the power spectral density of angular micro vibration signals of multiple spacecraft OLYMPUS, ETS-VI, OICETS and MICIUS. Then, the optimal distribution model is determined by comparing the determination coefficient R2 of the single distribution model and the mixed distribution model with the fitting signal of pointing error. The results show that the mixed distribution model composed of Gaussian distribution and Rice distribution has the highest fitting degree. Taking the Olympus aircraft as an example, the fitting degree of the Gaussian-Rice mixed distribution model is 27.44% higher than that of the single distribution model Rayleigh model, and the bit error rate deviation is reduced by 2.87 dB.

Keywords

• aircraft angular micro-vibration
• pointing error model
• single distribution
• mixed distribution