论文部分内容阅读
天文导航具有自主性强、精度高和误差不随时间积累等优点,惯性导航系统常采用天文观测的方法来提高定位和定姿精度,全天时星跟踪器技术成为近年来国内研究的热点。近红外系统多基于2MASS星表产生导航星表,系统工作中需要对可观测恒星进行排序,实现对恒星的最优选择。本文阐述了2MASS近红外恒星的测星能力计算方法,利用给出的信噪比(Signal noise ratio:SNR)计算公式,对一组亮背景条件下的恒星SNR进行了计算,并据此进行了理论排序。利用外场观星试验拍摄的星图,计算了恒星星点的SNR,并按照实测星点SNR对恒星进行了排序。计算结果表明:导航恒星的理论SNR与实测SNR的排序结果完全一致。
Astronavigation has the advantages of strong autonomy, high precision and error accumulation over time. The inertial navigation system often uses astronomical observation methods to improve the positioning and attitude accuracy. The star-tracker technology has become a hot research topic in recent years. NIR system based on 2MASS table multi-star navigation catalog, the system needs to be observable stars in order to achieve the optimal choice of stars. This paper describes the calculation method of the star power of 2MASS near-infrared stars. Based on the given signal-noise ratio (SNR) formula, the star SNR under a bright background condition is calculated, and based on this, Theory of order. Using the star map taken by the field stargazing test, the SNR of the star point is calculated and the stars are sorted according to the measured star point SNR. The calculation results show that the theoretical SNR of the navigation star is completely consistent with the measured SNR.