Guide star catalog generation for short-wave infrared (SWIR) All-Time star sensor

As an important part of All-Time star sensor design, the generation of the short-wave infrared (SWIR) guide star catalog is crucial to the system performance. The generation process needs estimation of the instrument magnitude and the guide star selection. Different from the commonly used star sensors, since the SWIR band is far away from the visual band and the detectable magnitude limit of the All-Time star sensor is dynamically changing as the observation conditions vary, the current methods of estimating the instrument magnitude cannot be directly applied and the catalog obtained through the current reduction methods that mainly aimed at improving the distribution uniformity cannot ensure enough stars measured in the field of view under strong sky background radiation. To solve the problems, we propose a method for guide star catalog generation for the All-Time star sensor. First, through the specific analysis of the spectral response curves of the SWIR detector and 2MASS detection bandpasses, the method of estimating instrument magnitudes for the All-Time sensor is determined. Subsequently, dynamic detectable magnitude limits are determined through the signal-to-noise model and the atmospheric background radiation intensity analysis. Based on the dynamic detectable magnitude limits, a reduction method is proposed. The simulation experiment results indicate that the RMS error of the estimation of instrument magnitude is 0.075. Compared to the magnitude filtering method, the guide star catalog obtained through our method can guarantee the completeness, besides, the global distribution uniformity increases by 2.2 times and the local distribution uniformity increases by 10.7 times.