# An Overview of GEO Satellite Communication Simulation Systems
###### Abstract  
Geostationary Earth orbit (GEO) satellite communication systems have become increasingly significant in global communication networks and national strategic infrastructure, owing to their advantages of extensive coverage, high capacity, and robust reliability. Constructing accurate and reliable simulation systems is essential to support the design, evaluation, and optimization of GEO satellite communication systems. This article first reviews the current developments and application prospects of GEO satellite communication systems and highlights the critical role of simulation technologies in system design and performance assessment. Subsequently, a systematic analysis is conducted on two core modules of simulation systems, i.e., coverage analysis and resource management and scheduling. Moreover, this article provides a comprehensive comparison and evaluation of mainstream satellite communication simulation platforms and tools. This review aims to offer valuable insights and guidance for future research and applications in GEO satellite communication simulation, thereby promoting technological innovation and advancement in related fields. GEO satellite communication system; simulation system; coverage analysis; resource management and scheduling; simulation platform and tool 20252  
These initiatives aim to integrate GEO with medium Earth orbit (MEO) and low Earth orbit (LEO) satellite systems into a unified mobile communication framework [2], ultimately fostering a fully integrated space-air-ground communication network that supports global digital connectivity and reinforces national strategic security. Due to the high cost, complex design, and wide coverage requirements, simulation platforms are critical to GEO satellite communication systems. Simulation supports orbit and constellation design, link analysis [3], coverage evaluation [4], and resource scheduling optimization [5; 6], helping reduce trial-and-error costs and enhance system reliability. In recent years, extensive research on the modeling and simulation of GEO satellite communication systems has been conducted by both academia and industry. For example, the National Aeronautics and Space Administration (NASA) developed the SATCOM Modeling Tool (SMT), which facilitates satellite constellation design, communication link simulation, and resource scheduling tests. Similarly, the European Space Agency (ESA) introduced the SatNetSim system to assess end-to-end communication performance within multi-orbit satellite network architectures. In addition, the Chinese Academy of Sciences has proposed an integrated space-air-ground information network test platform based on cloud-native technologies [7]. The GEO satellite communication simulation system primarily comprises four core modules: orbit and constellation modeling, communication link modeling, coverage analysis, and resource management and scheduling. Their functional roles, data flows between them, and the representative simulation tools adopted for each module are illustrated in Figure 1. Orbit and constellation modeling is responsible for generating and updating the trajectories and constellation configurations to provide essential geometric and spatiotemporal data for the overall simulation. Currently, modeling techniques have become increasingly precise [8]. The communication link modeling module, which integrates the functions of traditional physical layer communication modeling and channel modeling, is primarily used to estimate key link performance parameters such as path loss, link margin, and available throughput. Typically driven by parameter tables, this module employs models such as free-space path loss, standard atmospheric attenuation, and empirical formulas, providing reliable support for performance evaluation at the system level [9; 10].