# Real-Time Simulation and Sensor Performance Evaluation of Space-Based Infrared Point Target Group
## 1 Introduction  
With the development of computer-based visual simulation technology, infrared imaging simulation has received increasing attention. Many integrated scenario infrared visual simulation systems have been developed abroad [1; 2; 3; 4; 5; 6]. These systems play an important role in the design and evaluation of sensors. Space targets are often observed as point targets on images due to their distance from sensors, making it challenging to obtain complete and accurate data. Therefore, simulation is necessary to supplement real data. The Systems Tool Kit/electro-optical and infrared sensors (STK/EOIR) module takes into account the interactions between sensors, targets, and the environment to establish a customizable, high-confidence optoelectronic sensor model. This model can provide accurate data support for the simulation of spatial point target groups. One study [7] provides an overview of the simulation process of this module and analyzes the simulation results. However, it does not address the performance overhead that this module brings to system operation during calculation. At the same time, STK has limitations with respect to simulation objects. For example, when the target is in deep space with stars as the main background element, users can only make simple adjustments based on the software's built-in star catalog. Additionally, detailed infrared simulation results are only displayed within the software and cannot be output together with the simulation images. This makes it difficult to create datasets for follow-up target detection and recognition algorithms. In the area of stellar research, several publicly available infrared star catalogs have been established by missions that observe stars [8; 9; 10; 11; 12; 13]. They provide precise materials forstellar simulations. [PERSON] et al. [14] analyzed various all-sky survey programs and their generated infrared catalogs, selected suitable stars for astronomical infrared calibration, and integrated atmospheric effects. [PERSON] et al. [15] proposed a method of stellar energy extrapolation for multiple catalog data and calculated the relationship between magnitude and point source irradiance. [PERSON] et al. [16] obtained the stellar backgrounds of different observatories in the visible range by using the Hipparcos catalog with space time conversion. [PERSON] et al. [17] and [PERSON] et al. [18] developed a radiative generation model of the starry sky point source background based on the MSX catalog and simulated images in the corresponding wavelength bands, emphasizing the spatiotemporal accuracy of star background generation. However, these studies did not address the efficiency of visual simulation or the presence of targets in the scenario. STK provides two connection modes to aid users in secondary development. Early system development is generally connected through Connect mode. [PERSON] et al. [19] designed a multi-target flight simulation system with micromotion characteristics using MATLAB and STK. [PERSON] et al. [20] delved into the method of system integration between Visual C++ (VC) and STK to realize the combination of STK simulation and VC data analysis. [PERSON] et al. [21] improved the Connect mode calling method to reduce the complexity of type conversion. [PERSON] et al. [22] used High-Level Architecture (HLA) to solve the problem of rapid integration of verification systems in space orbit through the interconnection of VC and STK. Owing to the many inconveniences of using Connect mode, the newly introduced component object model (COM)-based approach has been gradually adopted by external systems to complete connection and control work in recent years. [PERSON] et al. [23] analyzed the applicable scenarios of MATLAB under the two development approaches and simulated the Global Navigation Satellite System (GNSS) constellation. [PERSON] et al. [24] implemented a three-dimensional scene display for radar simulation based on Microsoft Foundation Class (MFC) and COM. [PERSON] et al.