AoI-Aware Adaptive Relaying in Buffer-Aided Wireless-Powered NOMA Network with Random Arrivals

In this paper, we considered an age of information(AoI)-aware adaptive relaying scheme in buffer-aided wireless powered non-orthogonal multiple access(NOMA) network, where one buffer-aided source node is supposed to deliver two data streams to two destination nodes with the help of one buffer-aided relay node. Meanwhile, the data streams for two destination nodes are independently and randomly generated. The buffer-aided relay node is supposed to provide energy to source node through wireless energy harvesting technology, and forward two data streams received from source node to two destination nodes through downlink NOMA technology. For this buffer-aided wireless powered NOMA network, the long-term weighted average AoI minimization problem was formulated. By using Lyapunov optimization framework and subdividing the long-term weighted average AoI minimization problem into multiple subproblems, we obtain an adaptive AoI-aware relaying scheme for buffer-aided wireless powered NOMA network. Our analysis results indicate that, by adaptively adjusting the transmission rate, transmission powers, and optimizing the selection of appropriate transmission modes, the long-term weighted average AoI performance at two destination nodes can be optimized. In addition, numerical analysis results show that the proposed AoI-aware adaptive relaying scheme provides an effective relaying scheme for buffer-aided wireless powered NOMA relay network.