A Weighted Semi-Distributed Routing Algorithm for LEO satellite networks

Satellites play a major role in the development of a global information infrastructure. Developing a specialized, efficient and robust routing algorithm in Low Earth Orbit (LEO) satellite networks is a challenge in both research and practice. For example, algorithms based on topology can find the shortest path but the complexity of time and space is high; some algorithms based on Datagram Routing Algorithm (DRA) have a high computation overhead; others based on Dynamic Source Routing (DSR) store all route information in datagram, which however negatively impacts routing efficiency and robustness. In this paper, we propose a Weighted Semi-Distributed Routing Algorithm (WSDRA) that discovers a path with minimum propagation delay by using delicate information of two routing hops. This design can reduce computation overhead up to 50% compared to DRA. Low-cost ground networks are also embraced in WSDRA by applying a weighed cost function to describe path cost. In particular, we design a new antenna structure to cross Counter-Rotating Seam in order to shorten a routing path. We evaluate the propagation delay through both simulations and practical tests. The results show that the proposed algorithm is more efficient and robust than DRA and the delay can be reduced about 50% after adopting the new antenna structure. (C) 2015 Elsevier Ltd. All rights reserved.