Improving Network Performance in Hybrid Wireless Networks Using a Satellite Overlay

Large wireless networks have the ability to provide rapid connectivity in disaster areas or to interconnect users in far-flung geographical locations. However, limitations on performance and robustness have delayed the adoption of such networks. In this paper, we show that by the addition of a satellite overlay network, the performance and robustness of large-scale wireless networks can be greatly improved and thus make their deployment possible. We define a satellite overlay network as consisting of one or more satellite nodes and multiple terrestrial ``gateway'' nodes that have interfaces for both satellite links and terrestrial wireless communication. We divide the terrestrial network into multiple ``clusters'' of wireless nodes, with each cluster being served by one or more gateway nodes. Ordinary terrestrial user nodes reach the gateway node through multi-hop terrestrial paths. We thus propose a design for a hybrid satellite and terrestrial wireless network. Through network modeling and simulation, we show that significant improvement in end-to-end performance is possible in a wireless network when the satellite overlay is present, in comparison to the performance in flat wireless networks. Our results are for both stationary and mobile ground wireless nodes.