摘要
This letter investigates a delay optimization problem in device-to-device(D2D)networks where users have pre-downloaded subfiles following a coded caching rule.Due to acquiring rest subfiles,users may suffer both receiving and transmitting delays.To achieve the delay minimization,we first propose a delay-aware mode-selection strategy to adaptively choose multicast or D2D communications mode to reduce the receiving-caused delay.By matching these transmit modes with distinct subfile sizes,we further formulate a min-max optimization problem to minimize the delivery delay.Finally,numerical results prove that the proposed scheme outperforms existing ones in terms of both receiving and transmitting delays.
This letter investigates a delay optimization problem in device-to-device(D2D) networks where users have pre-downloaded subfiles following a coded caching rule. Due to acquiring rest subfiles, users may suffer both receiving and transmitting delays. To achieve the delay minimization, we first propose a delay-aware mode-selection strategy to adaptively choose multicast or D2D communications mode to reduce the receiving-caused delay. By matching these transmit modes with distinct subfile sizes, we further formulate a min-max optimization problem to minimize the delivery delay. Finally, numerical results prove that the proposed scheme outperforms existing ones in terms of both receiving and transmitting delays.
基金
partly supported by the National Natural Science Foundation of China (No.61601334,61601509)
