Adaptive access strategy for satellite-terrestrial optical networks based on particle swarm optimization algorithm

Satellite-to-terrestrial laser communications offer high bandwidth and security, making the integration of satellites and terrestrial infrastructure into a high-speed communications network critical. In satellite-terrestrial optical networks (STON), frequent link handovers necessitate an efficient access process to establish high-capacity and reliable laser links. We propose a novel and efficient optical network satellite adaptive access (ONSAA) strategy to reduce satellite access frequency while enhancing network capacity. For the first time, this strategy integrates the unique Pointing, Acquisition, and Tracking (PAT) process of satellite laser communication. The satellite access process is divided into two parts: satellite selection and the PAT process. Optimizing these two components independently can improve overall network performance. To optimize satellite selection, We apply a particle swarm optimization (PSO) algorithm, which effectively balances the capacity and dynamics of STON. Additionally, we propose a multi-scans method for the PAT process to increase satellite access success rates, thereby reducing the frequency of access requests. This method also minimizes docking delay, which in turn extends the link transmission time for successful connections between the optical ground station (OGS) and the satellite network. Docking delay refers to the time required to successfully access the satellite. Simulation results demonstrate that this strategy reduces the number of accesses and enhancing network capacity, while the optimized PAT process ensure fast and reliable connections presenting a promising solution for future STON applications.