Gateway Placement for Reliability Optimization in 5G-Satellite Hybrid Networks

The placement of satellite gateways, as critical devices for data transmission between terrestrial networks and satellites, is of fundamental importance for the design of 5G-satellite hybrid networks, especially for the network reliability since the satellite links are prone to failing due to poor meteorological conditions. To the best of our knowledge, this problem almost remains untouched. Existing works in this line mainly focused on gateway placement in wireless mesh networks and sensor networks, which have totally different network topologies and optimization targets, and thus cannot be readily adopted. In light of this, two algorithms are proposed as our solutions, i.e., an optimal enumeration algorithm (OEA) and a cluster based approximation placement algorithm (CAPA). Extensive experiments based on real world online network topologies have been conducted and as validated by our numerical results, OEA can obtain an optimal result with computational complexity of O(kn$C-{n}^{k}$) and CAPA can achieve a near-optimal solution with much lower computational complexity of O(n²).