A message transmission scheduling algorithm based on time-domain interference alignment in UWANs

• DOI: 10.1007/s12083-020-01058-2
• Publication Date: 2021-01-29T18:02:50Z
• Authors: Nan Zhao; Nianmin Yao; Zhenguo Gao
• Keywords: 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology

High propagation delays cause message collisions at intended nodes, which seriously affects network performance. In this paper, we consider the transmission scheduling problem of messages with specified transmission requirements, which is ignored by most MAC protocols of Underwater Acoustic Networks (UWANs). We focus on the actual applications of UWANs and adopt time-domain interference alignment to design a scheduling algorithm (TDIA-MAC). Firstly, we study the nature and the existence conditions of perfect scheduling. Secondly, we analyze the constraints required for feasible transmissions and design the value function to evaluate feasible transmissions. The optimal decision is selected from feasible transmissions by the value function. The algorithm meets the message transmission requirements in practical applications and ensures that multiple nodes can work simultaneously without conflicts. Finally, we simulate the proposed algorithm under two settings of varying offered traffic and the number of nodes. The results show that the TDIA-MAC outperforms the other three algorithms in terms of throughput, successful delivery ratio, and fairness under varying offered traffic and the number of nodes.