## 1 Introduction  
Near-Earth satellite-UAV collaborative networks are a ubiquitous IoT system that integrates synchronous satellites or medium- to low-orbit satellites and includes stratospheric balloons and manned or unmanned drones [1]. It not only effectively enhances network critical performance but also breaks geographical limitations, achieving seamless, global three-dimensional coverage and supporting users' access anytime, anywhere, bridging the digital divide between different regions. The UAV serves as an airborne mobile terminal, representing a novel node in satellite-based IoT. With the advantages of low cost, wide coverage, flexibility, and high line-of-sight [2], UAVs are widely used to assist in IoT data collection and provide a more accurate and robust data stream [3] for connecting global satellite-UAV collaborative IoT systems. For example, employing UAVs to patrol a designated area allows for clearer observations of crop growth [4] and natural disasters [5] than satellite remote sensing. Drone-assisted autonomous navigation [6], camera shooting [7], and outdoor positioning technology [8] can help with Building Information Modeling (BIM) for construction [9]. The satellite-UAV collaborative IoT systems scenario is shown in Figure 1.  
Moreover, the emergence of new business and application scenarios (such as digital twins [10] and industrial Internet of Things [11]) and their increasingly stringent key performance indicators necessitate the deep integration of communication, information, big data, AI, and control technologies within the ubiquitous communication systems. This integration further supports a cloud-native, flexible, streamlined, intelligent, secure, and open network, providing distributed, cross-domain, flexible, and agile expansion capabilities. This IoT system of near-Earth satellite-UAV collaboration differs fundamentally from ground-based IoT systems. Firstly, each satellite and drone is in constant high-speed motion relative to the earth and ground infrastructure. Secondly, the internode distances and visibility change over time. Lastly, the onboard computing load capabilities of the nodes are limited, especially for older satellites and mini-drones, which may have insufficient processing power. These characteristics present unique challenges for space-based IoT. Furthermore, the nodes of satellite-UAV collaborative IoT systems are exposed to the harsh space environment of deep vacuum and suffer from extreme weather, radiation, intense vibrations, and extreme temperature ranges. These factors result in much higher uncertainties in network communication compared with traditional ground-based IoT networks. The characteristics of low energy consumption and relatively long flight time of drones, as well as their ability to effectively expand coverage, are receiving increasing attention. Consequently, more and more researchers are engaging in exploratory studies [1; 11; 12] related to near-Earth satellite-UAV collaborative IoT system initiatives. This work aims to design a reliable, secure, and controllable network topology optimization algorithm that can adapt to various complex scenarios, enabling the rapid and efficient establishment  
Figure 1: The satellite–UAV collaborative IoT systems scenario. Schematic diagram of the integration of satellites and drones in the Internet of Things. Compared with satellite remote sensing, drones can more accurately observe crop growth and natural disasters and model the construction of buildings (BIM). of highly resilient networks while fulfilling communication tasks. Compared with the traditional methods that focus too much on solution efficiency, the innovation of the proposed method is that instead of choosing the two aspects of neighborhood solution generation and estimation function computation as the entry point of optimization, a new optimization path is provided.