A remote sensing data transmission strategy based on the combination of satellite-ground link and GEO relay under dynamic topology

The low earth orbit (LEO) remote sensing satellite has a short communication time with the earth station (ES), and a large amount of remote sensing data cannot be transmitted back to the ES in time using the LEO-ES link during the communication period. Using relay satellites can indirectly increase the amount of data transmitted back from LEO. In this paper, we combine LEO- ES link and relay satellite offloading to study the problem of maximizing the amount of data transmitted back from LEO remote sensing satellites. Most of the existing methods do not consider the effect of topology change on policy. In this paper, we consider a three-layer satellite network architecture of geostationary earth orbit (GEO), LEO remote sensing satellite , and ES. We studied the problem of maximizing the amount of LEO transmitted back data under dynamic topology between layers, and proposed a transmission strategy based on a combination of LEO-ES link and GEO offload under dynamic topology. First, in order to reduce the number of link interruptions in each time slot, a Non-Uniform Time Slot Division Method (NUTSDM) based on visible relationships between layers is proposed based on discrete-time points, which helps to accurately determine the number and identity of LEOs competing under each time slot. Second, the relationship among GEOs, LEOs, and network administrators is modeled as a Stackelberg game model, and a Two-way Bargaining Game Scheme under Dynamic Topology (TWBGS-DT) is proposed to maximize the amount of data transmitted back from space. Compared with the existing methods, the experimental results confirm the effectiveness of the proposed scheme in terms of algorithm convergence speed, terms of pricing, GEO cache space allocation, and increase the data volume of LEO transmissions back by 11.5% and 8.2 times relative to the ISL-Aided strategy and GAA-FARR strategy, respectively.