Bidirectional Scanning Based Medium Access Control Algorithm in Directional Aviation Relay Network with Multiple Air Nodes

Directional aviation relay networks are widely used to improve the performance of ad hoc networks. Aiming at the disadvantage of large data packet delay of directional aviation relay network with single air node, this paper proposes a medium access control algorithm based on multiple air nodes and bidirectional scanning, which can effectively reduce the total delay of data packets. First, the algorithm divides multiple air nodes into two groups, using clockwise and counterclockwise scanning modes respectively, to provide data relay and forwarding services for ground nodes. According to the number of air nodes and their scanning mode, as well as the sector in which the destination node of the to-be-sent traffic is located, the ground nodes determine whether the to-be-sent traffic uses a single-aircraft relay two-hop transmission or a double-aircraft relay four-hop transmission link in a distributed manner. Secondly, the theoretical model of unidirectional scanning and bidirectional scanning algorithm is built, and the theoretical packet delay distribution law of the two algorithms as well as the optimal ratio of bidirectional scanning algorithm in reducing packet delay compared with unidirectional scanning algorithm is obtained. Finally, the performance of the proposed algorithm is verified by simulation. The simulation results are consistent with the theoretical analysis, which show that in the case of 4 to 8 air nodes, compared with unidirectional scanning algorithm, the total delay of packets in bidirectional scanning algorithm is reduced by 23.10 $$\%$$ –28.81 $$\%$$ .