# Service-Driven Dynamic Beam Hopping with Resource Allocation for LEO Satellites
## 1 Introduction  
With the rapid development of communication technologies, users' demands for high-quality and full-domain coverage communication services are growing increasingly. Although terrestrial communication networks are continuously improving, coverage blind spots still exist in remote areas and special scenarios, which makes satellite communication systems an indispensable supplementary solution [1, 2]. Satellite communication systems possess advantages such as wide coverage and strong communication capabilities, which are highly compatible with the development needs of communication networks in the 6G era [3]. In the field of satellite communication, compared with Geostationary Orbit satellites, Low-Earth-Orbit (LEO) satellites have become a research hotspot due to their shorter round-trip delay and lower signal path loss [4]. However, due to the non-uniform spatial distribution of ground users, the time-varying nature of user service requests, and the high-speed movement characteristics of satellites, service demands become dynamicallyunbalanced in the spatial dimension [5]. Additionally, the resources of LEO satellites are limited by objective factors, such as satellite volume, weight, and energy reserves. Therefore, how to make full use of limited resources to match complex and changeable service demands has become a major challenge faced by power-constrained LEO satellite communication systems [6; 7], especially in application scenarios such as sudden events and peak traffic periods, where the rapid change of user demands places higher requirements on the intelligence and flexibility of resource allocation mechanisms. Multi-beam satellites can generate many beams and improve service quality and system capacity through flexible allocation of beam resources, playing an important role in solving the above problems [8]. However, there are still many difficulties in truly achieving efficient utilization of LEO satellite resources [9]. In power-constrained multi-beam satellite communication systems, traditional static resource allocation schemes struggle to cope with complex and changeable communication demands. To ensure the quality of service for high-data-rate services, it is necessary to introduce beam hopping technology [10]. Traditional fixed resource allocation methods are prone to resource waste and ineffective coverage problems when facing application scenarios with uneven traffic demands. In contrast, beam hopping technology can effectively adapt to the non-uniform distribution characteristics of traffic demands by dynamically adjusting beam pointing, coverage areas, and transmission power, thereby significantly improving resource utilization. For beam hopping optimization problems, traditional iterative algorithms and heuristic algorithms have a lag in real-time response, and simply relying on data-driven methods may lead to optimization difficulties, invalid constraints, and performance degradation. Therefore, it is necessary to explore new optimization methods [11]. To better adapt to the changes in time-varying traffic demand distribution, the authors of [12] designed a beam switching scheme suitable for beam hopping systems in LEO satellites, providing a fundamental framework for addressing the challenges of limited resources and dynamic demands. In [13], the authors propose dividing the satellite coverage area into multiple fine-grained clusters, dynamically serving different clusters based on user demands. This approach not only effectively avoids inter-cluster spectral interference but also enables flexible resource allocation. The authors transform user traffic demands into a Markov Decision Process (MDP) in [14], offering a modeling paradigm for the subsequent processing of traffic demands and decision making in resource allocation.