A TDMA Protocol Based on Data Priority for In-Vivo Wireless NanoSensor Networks

Terahertz based in-vivo Wireless NanoSensor Networks (iWNSNs) implant nano-scale sensor nodes into the body, and use the human body as the network center to remotely monitor vital signs. Due to the characteristics of the terahertz channel in the body and the limited resources of nano-devices, the MAC protocol of the traditional Wireless Sensor Network is not suitable for iWNSNs. In this paper, a MAC protocol based on data priority, called DPB-MAC, is proposed. This protocol considers the difference of node data services in the network and prioritizes the services of the source node according to the timeliness of the data and the energy consumption of the node itself. Subsequently, a queuing mechanism is introduced on the basis of TDMA, and the time slots of the transmission phase are allocated according to the number of nodes in the network and the priority of the node data service, thereby avoiding conflicts between nodes. Simulations results show that the protocol can effectively reduce the average end-to-end delay and improve the average throughput.