Research On Interference Management And Channel Allocation Strategies For LEO Satellite Communications

Low Earth Orbit(LEO)satellites have the advantages of wide coverage,low transmission delay and small geographical restrictions.LEO satellite networks can achieve global Internet and are an important component of the global integrated communication network.As the demands for communication service increase,users have increasingly high requirements for system capacity and service quality in satellite communication.LEO satellite systems are inevitably constrained by onboard resources,including inefficient utilization of resources such as spectrum,power,computing,and storage.Therefore,efficient allocation onboard resources are of great significance for the development of LEO satellite communication.This paper focuses on LEO satellite communication systems,adopts a user-centric virtual cell concept,reduces inter-beam interference while designing efficient dynamic channel allocation strategies for users.The main research contents are as follows:(1)Constructing a user-centric virtual cell inevitably leads to overlap between virtual cells,which in turn results in significant inter-cell interference during collaborative transmission between virtual cells,leading to a degradation in system performance.In order to reduce inter-cell interference,this paper proposes a virtual cell interference management strategy based on the Artificial Bee Colony(ABC)algorithm.Virtual cells are constructed based on the received signal power of users,and the interference strength between virtual cells is calculated to merge virtual cells into virtual cell clusters,thereby converting inter-cell interference into intra-cluster interference.Finally,interference elimination is performed through precoding technology to improve system transmission rate.(2)Due to the non-uniform distribution of users in virtual cell clusters,uneven load distribution leads to low channel utilization and poor service quality within the clusters.In order to improve channel utilization,LEO satellites use full-band multiplexing technology,but this technology brings serious inter-beam interference.In addition,the requirement for multiple satellite coverage further exacerbates the inter-beam interference.To resolve these above problems,this paper propose a LEO channel allocation strategy based on the ABC algorithm.The strategy considers the difference in inter-beam communication traffic and inter-channel interference,establishes a binary integer programming model for the channel allocation problem and uses the ABC algorithm to allocate channels to maximize system throughput.At the same time,to accelerate the convergence of the ABC algorithm and improve global search capability,global optimal solutions and adjustment factors are introduced to make the proposed channel allocation scheme adaptable to differences in beam traffic and improve channel utilization and system throughput.The simulation results show that the proposed strategy has excellent performance in terms of blocking rate and system throughput.