An Optimized Contact Graph Routing Algorithm in Deep Space Communication

Aiming at the problem of long transmission delay and frequent link interruption in deep space, and it is difficult for contact graph routing algorithm to deal with the temporary changes of network topology. An optimized contact graph routing algorithm based on capacity constraints is proposed, which takes the capacity constraint into consideration in calculating of the earliest arrival path. At the same time, the number of forwarding paths is determined according to the link state information and the network topology. Through effectively utilize the nodes' contact opportunities to increase the successful delivery ratio while limit the amount of copies in the network, which balances the performance and resource consumption. Simulation results show that the delivery ratio can be improved by 29.5% without retransmission, and the transmission delay can be reduced by 13.4% while network overhead is reasonable, which effectively adapt to deep space environment.