Real-Time TT&C Access Scheduling in Satellite Mega-Constellations: A Networked-Enhanced and Attention-Driven Learning Approach

Abstract

Real-time telemetry, tracking, and command (TT&C) access scheduling is essential for ensuring stable operation and mission execution in satellite mega-constellations. However, due to visibility-constrained satellite–ground access time windows and the limited spatial availability of access antennas and multi-band frequencies, TT&C resources—access entities such as ground stations and relay satellites—exhibit strong spatio-temporal resource utilization interdependencies (e.g., antenna access contention across frequency bands and visibility conflicts) among mission access requests, thereby exacerbating the challenges of real-time TT&C mission responsiveness in satellite mega-constellations. To address the challenges, we propose a Networked-Enhanced TT&C (NETC) scheduling framework that leverages inter-satellite links (ISLs) to provide auxiliary access bands during non-visibility periods, thereby enhancing real-time responsiveness of TT&C Mission Access (TCMA) without additional infrastructure cost. Based on the NETC, we model the TCMA problem and then construct a Spatio-temporal Resource Availability Graph (SRAG) to efficiently decouple its high-dimensional solution space. Based on this, we further propose an Attention-Mechanism-Driven Deep Reinforcement Learning (AMDRL) algorithm that focuses on real-time, high-priority utilization of TT&C spatio-temporal access resources and enables dynamic awareness of evolving spatio-temporal resource utilization states, thereby supporting real-time mission scheduling decisions even in highly dynamic mega-constellation environments. Extensive simulations show that our method significantly realizes faster convergence, better spatio-temporal resource utilization, and stronger real-time mission responsiveness performance—achieving 1.8 times higher mission completion efficiency and maintaining second-level mission responsiveness even under concurrent TT&C for mega-constellations.